Patent Publication Number: US-2011070861-A1

Title: XML Protocol For The CMSP Gateway To CBC Interface In The CMAS Architecture

Description:
BACKGROUND 
     The Emergency Alert System (EAS) enables federal, state, and/or local governments to provide timely messages and alerts to the public regarding various types of emergencies. For example, the public can receive messages pertaining to weather conditions, disasters, AMBER (America&#39;s Missing: Broadcast Emergency Response) alerts, and the like. The EAS is jointly administered by the Federal Communications Commission (FCC), the Federal Emergency Management Agency (FEMA), and the National Weather Service (NWS). 
     EAS alert messages can be issued nationally (i.e., across the entire United States) or within a specific geographic region within the United States. For example, an EAS alert message can be issued for a specific area affected by a natural disaster, such as a hurricane or a flood. The area covered by the alert may span a portion of one or more states, and may cover tens or even hundreds of square miles depending on the type and severity of the emergency. 
     EAS alert messages are generally communicated via radio and television broadcasts. However, other types of communication mediums (e.g., cellular networks, local wireless networks, the Internet, cable networks, etc.) have been contemplated. 
     SUMMARY 
     Protocols for communications in a Global System for Mobile Communications (GSM) and/or Universal Mobile Telephone System (“UMTS”) communications network are described. More specifically, in an example embodiment, Extensible Markup Language (XML)-based protocols for interfacing a Cellular Broadcast Entity (CBE) with a Cellular Broadcast Center (CBC) in GSM and/or UMTS networks are described. In at least one embodiment, the communications include Emergency Alert System (EAS) messages, and the protocol is applied to the EAS messages. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram of an example GSM communications network in which embodiments of the CBE-CBC protocol can be implemented. 
         FIG. 2  is a diagram of an example UMTS communications network in which embodiments of the CBE-CBC protocol can be implemented. 
         FIG. 3  is a flow diagram of a process depicting an example valid call flow between a CBE and a CBC. 
         FIG. 4  is a flow diagram of a process depicting an example invalid call flow between a CBE and a CBC. 
         FIG. 5  is a depiction of an example CBE message (CBEM) object model. 
         FIG. 6  depicts a block diagram of an exemplary packet-based mobile cellular network environment, such as a GPRS network, in which communications between a CBE and a CBC in accordance with an XLM-based protocol can be implemented. 
         FIG. 7  illustrates an architecture of a typical GPRS network in which communications between a CBE and a CBC in accordance with an XLM-based protocol can be implemented. 
         FIG. 8  illustrates an exemplary block diagram view of a GSM/GPRS/IP multimedia network architecture within which communications between a CBE and a CBC in accordance with an XLM-based protocol can be implemented. 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     In an example embodiment, an Extensible Markup Language (XML)-based protocol is utilized for communications between a Cellular Broadcast Entity (CBE) and a Cellular Broadcast Center (CBC) in a Commercial Mobile Alert System (CMAS) architecture. The CMAS architecture supports commercial mobile alerts. The CBE is a new entity in the CMAS architecture. The CBE receives alert messages from the Federal Alert Gateway and interfaces to (communicates with) the CBC. The CMAS architecture can be implemented in various communications networks, such as a Global System for Mobile Communications (GSM) communications network and a Universal Mobile Telephone System (UMTS) communications network, for example. It is to be understood, that the herein-described protocol is not limited to applications in a CMAS architecture, but can be utilized by any appropriate general commercial cellular broadcast service. In an example embodiment, a CBE is the server, processor, or the like, that creates the message content that is to be broadcast by the Cell Broadcast Service. The CBE may be owned by the wireless operator or may be owned and operated by an external information source (e.g., news, traffic, weather, stocks, sports highlights, sports scores). In addition to the message content to be broadcast, the CBE can provide the general characteristics for the message broadcast such as number of times to repeat the broadcast, amount of time between broadcasts, and target area to receive the broadcast. In an example embodiment, the CBC is the server, processor, or the like, within the wireless operator network which controls and manages the broadcast of messages via Cell Broadcast. The CBC receives messages for broadcast from multiple CBEs and coordinates the broadcast of these messages among multiple cell sites. The CBC determines the set of cell sites in the target area specified in the message received from the CBE. The CBC manages the broadcast period and frequency based upon the instructions received from the CBE. The CBC manages multiple simultaneous message broadcasts among numerous cell sites via multiple GSM Base Station Controllers (BSCs) and UMTS Radio Network Controllers (RNCs). 
     Utilization of the herein-described CBE-CBC protocol can provide for ease of operation of the CMAS architecture and can facilitate interoperability in a multi-vendor and/or multi-provider environment. Utilization of the herein-described CBE-CBC protocol can simplify interoperability testing and mitigate, if not prevent, any need to build proprietary interfaces and perform interoperability testing with multiple vendors to ensure proper system operations. Utilization of the herein-described CBE-CBC protocol can aid in developing FCC compliant communications systems. Additionally, utilization of the herein-described CBE-CBC protocol can facilitate flexible designs consistent with the use of various types of servers being deployed within a network. 
       FIG. 1  is a diagram of an example GSM communications network in which embodiments of the CBE-CBC protocol can be implemented.  FIG. 2  is a diagram of an example UMTS communications network in which embodiments of the CBE-CBC protocol can be implemented. Referring to  FIG. 1  and  FIG. 2 , the CBE  12  receives alert messages from the Federal Alert Gateway, or the like, and interfaces to (communicates with) the CBC  14  in the GSM/UMTS networks depicted in  FIG. 1  and  FIG. 2 . In an example embodiment, the CBE-CBC protocol utilizes an XML schema for communications between the CBE  12  and the CBC  14 . In various embodiments, the XML schema is written to accommodate general cellular broadcast applications other than CMAS communications. Generally, the schema defines a CBC Request message sent from the CBE  12  to the CBC  14 , and contains the information required by the CBC  14  to broadcast the alert message, including the actual message contents and information such as repetition period, how long to broadcast, etc. The CBC  14  receives this alert message and uses the information to construct a GSM/UMTS Cellular Broadcast primitive to be delivered to the BSC and/or RNCs, as shown in  FIG. 1  and  FIG. 2 . The XML schema also defines a response message wherein the CBC  14  can inform the requesting entity, such as the CBE  12 , that the message was accepted and delivered, or an appropriate error indication. The XML schema also defines a method to update a previously issued alert message. 
       FIG. 3  is a flow diagram of a process depicting an example valid call flow between a CBE and a CBC. At step  16 , the CBE  12  determines to initiate the broadcast of a cellular broadcast message, update the broadcast of a previous cellular broadcast message, or cancel the broadcast of a previous cellular broadcast message. In an example embodiment, the cellular broadcast message contains an EAS alert message and/or associated information. For example, for emergency alerts, the CBE is the CMAS Alert Gateway which will receive emergency alert messages from the Federal government Federal Alert Gateway. The majority of these alerts are initiated by the National Weather Service based upon severe weather conditions such as tornados, flash floods, etc. Updates of these alert messages could be issued for National Weather Service for changes in the severe weather conditions (e.g., tornado movement). Any time that the National Weather Service determines that an emergency alert is no longer needed or if an emergency alert was issued in error, a Cancel message could be issued. At step  18 , the CBE  12  constructs a CBE to CBC request message in accordance with its determination at step  16 . Thus, at step  18 , the CBE  12  constructs one of a CBE to CBC initial request message, a CBE to CBC update request message, or a CBE to CBC cancel request message. More particularly, if, at step  16 , the CBE  12  determines to initiate the broadcast of a cellular broadcast message, at step  18 , the CBE  12  constructs a CBE to CBC initial request message. If, at step  16 , the CBE  12  determines to update the broadcast of a previous cellular broadcast message, the CBE  12 , at step  18 , constructs a CBE to CBC update request message. And, if at step  16 , the CBE  12  determines to cancel the broadcast of a previous cellular broadcast message, the CBE  12 , at step  18 , constructs a CBE to CBC cancel request message. 
     At step  20 , the CBE  12  sends the CBC request message, constructed at step  18 , to the CBC  14 . More particularly, if, at step  18 , the CBE  12  constructed a CBE to CBC initial request message, the CBE  12  sends the CBE to CBC initial request message to the CBC  14  at step  20 . If, at step  18 , the CBE  12  constructed a CBE to CBC update request message, the CBE  12  sends the CBE to CBC update request message to the CBC  14  at step  20 . And, if at step  18 , the CBE  12  constructed a CBE to CBC cancel request message, the CBE  12  sends the CBE to CBC cancel request message to the CBC  14  at step  20 . 
     The CBC  14  validates the received CBE to CBE request message at step  22 . Example types of message validation performed by the CBC include (1) validation of proper message structure and element format, (2) element values are with the ranges defined for the protocol, (3) verification that mandatory elements are present, and (4) verification that conditional elements are present as required based upon the contents of other elements. If validation passes (is successful) at step  22 , the CBC  14  acknowledges the received CBE to CBC request message at step  24 . That is, the CBC  14  sends an indication of acknowledgement and validation to the CBE  12 . 
     At step  26 , the CBC  14  processes the CBE to CBC request message and sends the acknowledgement to the CBE  12  at step  24 . The CBC can process the request message in various ways. Examples include: (1) determination of set of cell sites for the message broadcast based upon the geo-targeting information in the message, (2) determination of the set of BSCs and RNCs which are to be associated with this message broadcast, (3) calculation of Cell Broadcast repetition period and frequency periods, (4) formatting of the received CBE to CBC message into Cell Broadcast parameters and message contents, and/or (5) sending the created Cell Broadcast parameters and message contents to the determined set of cell sites via the associated set of BSCs and RNCs. 
       FIG. 4  is a flow diagram of a process depicting an example invalid call flow between a CBE and a CBC. At step  28 , the CBE  12  determines to initiate the broadcast of a cellular broadcast message, update the broadcast of a previous cellular broadcast message, or cancel the broadcast of a previous cellular broadcast message. In an example embodiment, the cellular broadcast message contains an EAS alert message and/or associated information. For example, for emergency alerts, the CBE is the CMAS Alert Gateway which will receive emergency alert messages from the Federal government Federal Alert Gateway. The majority of these alerts are initiated by the National Weather Service based upon severe weather conditions such as tornados, flash floods, etc. Updates of these alert messages could be issued for National Weather Service for changes in the severe weather conditions (e.g., tornado movement). Any time that the National Weather Service determines that an emergency alert is no longer needed or if an emergency alert was issued in error, a Cancel message could be issued. At step  30 , the CBE  12  constructs a CBE to CBC request message in accordance with its determination at step  28 . Thus, at step  30 , the CBE  12  constructs one of a CBE to CBC initial request message, a CBE to CBC update request message, or a CBE to CBC cancel request message. More particularly, if, at step  28 , the CBE  12  determines to initiate the broadcast of a cellular broadcast message, at step  30 , the CBE  12  constructs a CBE to CBC initial request message. If, at step  28 , the CBE  12  determines to update the broadcast of a previous cellular broadcast message, the CBE  12 , at step  30 , constructs a CBE to CBC update request message. And, if at step  28 , the CBE  12  determines to cancel the broadcast of a previous cellular broadcast message, the CBE  12 , at step  30 , constructs a CBE to CBC cancel request message. 
     At step  32 , the CBE  12  sends the CBC request message, constructed at step  30 , to the CBC  14 . More particularly, if, at step  30 , the CBE  12  constructed a CBE to CBC initial request message, the CBE  12  sends the CBE to CBC initial request message to the CBC  14  at step  32 . If, at step  30 , the CBE  12  constructed a CBE to CBC update request message, the CBE  12  sends the CBE to CBC update request message to the CBC  14  at step  32 . And, if at step  30 , the CBE  12  constructed a CBE to CBC cancel request message, the CBE  12  sends the CBE to CBC cancel request message to the CBC  14  at step  32 . 
     The CBC  14  attempts to validate the received CBE to CBE request message at step  34 . Example types of message validation performed by the CBC can include: (1) validation of proper message structure and element format, (2) element values are with the ranges defined for the protocol, (3) verification that mandatory elements are present, and/or (4) verification that conditional elements are present as required based upon the contents of other elements. If validation fails (is unsuccessful) at step  34 , the CBC  14  sends an error response message at step  36 . That is, the CBC  14  sends an indication that the attempt to valid the request message failed to the CBE  12 . 
     At step  38 , the CBE  12  processes the error message. Examples of how the CBE can process the error message include: (1) determination of set of cell sites for the message broadcast based upon the geo-targeting information in the message, (2) determination of the set of BSCs and RNCs which are to be associated with this message broadcast, (3) calculation of Cell Broadcast repetition period and frequency periods, (4) formatting of the received CBE to CBC message into Cell Broadcast parameters and message contents, and/or (5) sending the created Cell Broadcast parameters and message contents to the determined set of cell sites via the associated set of BSCs and RNCs. 
     In accordance with the XML protocol utilized to communication between the CBE and the CBC, the messages communicated between the CBE and the CBC, in an example embodiment, can comprise segments. Table 1 below contains a description of the exemplary CBE message segments. Each CBE to CBC message comprises a &lt;CBEM_CBS_Request&gt; segment, which may contain one &lt;CBEM_CBS_Message_Info&gt; segment and one or more &lt;CBEM_CBS_Geotargeting_Info&gt; segments. The CBEM_CBS_Request segment provides the elements that are used for management and handling of the CBEM message on the CBE to CBC interface including items such as message identifier, identification of sender, protocol version, type of CBEM message, etc. The CBEM_CBS_Request segment is required for all message type. 
     The CBEM_CBS_Message_Info provides additional information for initial message request and for update requests. This additional information is not required for all message types and therefore is contained in a separate segment. The additional information includes elements such as the message content, language indicators, repetition period, and number of rebroadcasts. 
     The CBEM_CBS_Geotargeting_Info segment defines the target area for the message. This additional information is not required for all message types and therefore is contained in a separate segment. Also since there can be multiple target areas defined for a specific message, the geo-targeting information is provided as a separate segment so that multiple occurrences of the geo-targeting information can be supported. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 CBE MESSAGE SEGMENTS 
               
            
           
           
               
               
            
               
                 CBE MESSAGE 
                 CBE MESSAGE SEGMENTS 
               
               
                   
               
               
                 CBE to CBC Initial 
                 one &lt;CBEM_CBS_Request&gt; segment 
               
               
                 Request Message 
                 one &lt;CBEM_CBS_Message_Info&gt; segment 
               
               
                   
                 one or more &lt;CBEM_CBS_Geotargeting_Info&gt; 
               
               
                   
                 segments 
               
               
                 CBE to CBC Update 
                 one &lt;CBEM_CBS_Request&gt; segment 
               
               
                 Request Message 
                 one &lt;CBEM_CBS_Message_Info&gt; segment 
               
               
                   
                 one or more &lt;CBEM_CBS_Geotargeting_Info&gt; 
               
               
                   
                 segments 
               
               
                 CBE to CBC Cancel 
                 one &lt;CBEM_CBS_Request&gt; segment 
               
               
                 Message 
               
               
                 Acknowledgement 
                 one &lt;CBEM_CBS_Request&gt; segment 
               
               
                 Response for CBE to 
               
               
                 CBC Message 
               
               
                 Error Response for 
                 one &lt;CBEM_CBS_Request&gt; segment 
               
               
                 CBE to CBC 
               
               
                 Message 
               
               
                   
               
            
           
         
       
     
       FIG. 5  is a depiction of an example object model for CBE messages. The object model depicted in  FIG. 5  represents the objects (or elements) of the XML protocol utilized for communication between the CBE and the CBC. The elements shown in the DBE message object model depicted in  FIG. 5  are described in detail in Table 2, Table 3, and Table 4 below. In the tables, an element is indicated as being: mandatory with an upper case letter M, conditional with an upper case letter C, or optional with an upper case letter O. It is to be understood, however, that the characteristics of mandatory, conditional, and optional, as shown in the table below for the respective elements is exemplary, and not intended to be limiting. A mandatory element is required when the associated segment is included in the CBE message. An optional element may be included in a segment. The entry in the Definition column defines when the element is optional and the interpretation of the missing optional element. A conditional element may be required in the segment depending on the contents of other elements. 
     Table 2 below describes example elements of the CBEM_CBS_Request segment. 
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                 CBEM_CBS_REQUEST SEGMENT ELEMENT DESCRIPTION 
               
            
           
           
               
               
               
            
               
                   
                 MANDATORY/ 
                   
               
               
                   
                 OPTIONAL/ 
               
               
                 CBEM ELEMENT 
                 CONDITIONAL 
                 DEFINITION 
               
               
                   
               
               
                 CBEM_CBS_Request 
                 M 
                 Identifies the segment with elements described in 
               
               
                   
                   
                 the following rows of this table. 
               
               
                   
                   
                 (1) Surrounds CBEM CBS Request segment sub- 
               
               
                   
                   
                 elements. 
               
               
                   
                   
                 (2) Must include the xmlns attribute referencing the 
               
               
                   
                   
                 CBEM URN as the 
               
               
                   
                   
                 namespace, e.g.: 
               
               
                   
                   
                 &lt;cbem:CBEM_CBS_Request 
               
               
                   
                   
                 xmlns:cbem=“urn:xxx:xxxxx:xx:cbem:1.0”&gt; 
               
               
                   
                   
                 [sub-elements] 
               
               
                   
                   
                 &lt;/cbem:CBEM_CBS_Request&gt; 
               
               
                   
                   
                 (3) In addition to the specified sub-elements, may 
               
               
                   
                   
                 contain one or more 
               
               
                   
                   
                 &lt;CBEM_CBS_Message_Info&gt; blocks. 
               
               
                 CBEM_protocol_version 
                 M 
                 The version of the CBEM protocol. 
               
               
                   
                   
                 Used by the CBE and the CBC to identify the 
               
               
                   
                   
                 protocol version of the CBEM protocol. 
               
               
                   
                   
                 The value of the CBEM_protocol_version element 
               
               
                   
                   
                 for this version of the standard shall be 1.0. 
               
               
                 CBEM_message_number 
                 M 
                 Identifies the unique message number of the 
               
               
                   
                   
                 message. This will be used by the CBC to 
               
               
                   
                   
                 generate the Serial Number parameter in the 
               
               
                   
                   
                 CBC Write-Replace indication. 
               
               
                   
                   
                 CBEM_message_number is a string uniquely 
               
               
                   
                   
                 identifying the message. The 
               
               
                   
                   
                 CBEM_message_number is assigned by the 
               
               
                   
                   
                 CBE. 
               
               
                   
                   
                 The value is assigned by the CBE, and may follow 
               
               
                   
                   
                 the format: 
               
               
                   
                   
                 &lt;CBE Identifier&gt;- &lt;message number&gt; 
               
               
                   
                   
                 where 
               
               
                   
                   
                 &lt;CBE Identifier&gt; is a unique string defined the 
               
               
                   
                   
                 CBE and &lt;message number&gt; where &lt;message 
               
               
                   
                   
                 number&gt; is the number assigned by the CBE to 
               
               
                   
                   
                 this message. 
               
               
                   
                   
                 The CBC shall be responsible for generating and 
               
               
                   
                   
                 required mapping of the 
               
               
                   
                   
                 CBEM_message_number to the CBC Serial 
               
               
                   
                   
                 Number parameter. 
               
               
                 CBEM_referenced_message_number 
                 C 
                 Identifies the referenced message number. This is 
               
               
                   
                   
                 used for CBE Updates or Cancel message types 
               
               
                   
                   
                 and is used by the CBC to associate the message 
               
               
                   
                   
                 with the previous message to be updated or 
               
               
                   
                   
                 cancelled. 
               
               
                   
                   
                 CBEM_referenced_message_number is a string 
               
               
                   
                   
                 uniquely identifying the message. The 
               
               
                   
                   
                 CBEM_referenced_message_number is assigned 
               
               
                   
                   
                 by the CBE. 
               
               
                   
                   
                 The value is assigned by the CBE, and may follow 
               
               
                   
                   
                 the format: 
               
               
                   
                   
                 &lt;CBE Identifier&gt;- &lt;message number&gt; 
               
               
                   
                   
                 where 
               
               
                   
                   
                 &lt;CBE Identifier&gt; is a unique string defined by 
               
               
                   
                   
                 the CBE and &lt;message number&gt; where 
               
               
                   
                   
                 &lt;message number&gt; is the number assigned by the 
               
               
                   
                   
                 CBE to this message. 
               
               
                 CBEM_sender_id 
                 M 
                 URI or IP address of the CBE sending the CBEM 
               
               
                   
                   
                 message. 
               
               
                 CBEM_message_type 
                 M 
                 This element identifies the message type for the 
               
               
                   
                   
                 request to the CBC. 
               
               
                   
                   
                 Code Values: 
               
               
                   
                   
                 “CBS Request” - A request to initiate a cell 
               
               
                   
                   
                 broadcast message with the information 
               
               
                   
                   
                 contained in the CBEM_CBS_Message_Info 
               
               
                   
                   
                 segment 
               
               
                   
                   
                 “CBS Update Request” - Updates and 
               
               
                   
                   
                 supersedes the earlier message(s) identified in 
               
               
                   
                   
                 &lt;CBEM_referenced_message_number&gt; 
               
               
                   
                   
                 “CBS Cancel Request” - Cancels the earlier 
               
               
                   
                   
                 message(s) identified in &lt; CBEM —  referenced —   
               
               
                   
                   
                 message —  identifier&gt; 
               
               
                   
                   
                 “Ack” - Acknowledges receipt and acceptance of 
               
               
                   
                   
                 the message(s) identified in 
               
               
                   
                   
                 &lt;CBEM_referenced_message_number&gt; 
               
               
                   
                   
                 “Error” indicates rejection of the message(s) 
               
               
                   
                   
                 identified in &lt; 
               
               
                   
                   
                 CBEM_referenced_message_number&gt;; 
               
               
                   
                   
                 explanation should appear in 
               
               
                   
                   
                 &lt;CBEM_response_description&gt; 
               
               
                 CBEM_response_code 
                 C 
                 This element contains the CBEM Response Codes 
               
               
                   
                   
                 (see clause 7.5 Definition of CBEM Response 
               
               
                   
                   
                 Codes) that may be returned from the CBC to the 
               
               
                   
                   
                 CBE in response to a received CBS request 
               
               
                   
                   
                 message via the CBE to CBC interface. This 
               
               
                   
                   
                 element is included when necessary based upon 
               
               
                   
                   
                 specific use case. 
               
               
                   
                   
                 Multiple instances may occur within a single 
               
               
                   
                   
                 &lt;CBEM_CBS_Request&gt; block. Each occurrence 
               
               
                   
                   
                 of the CBEM_response_code element should 
               
               
                   
                   
                 have a corresponding occurrence of the 
               
               
                   
                   
                 CBEM_response_description element. 
               
               
                 CBEM_response_description 
                 C 
                 The CBC may use the CBEM_response_description 
               
               
                   
                   
                 element to populate this element on messages 
               
               
                   
                   
                 from the CBC to the CBE. (See clause 7.5 
               
               
                   
                   
                 Definition of CBEM Response Codes). 
               
               
                   
                   
                 Multiple instances may occur within a single 
               
               
                   
                   
                 &lt;CBEM_CBS_Request&gt; block. Each occurrence 
               
               
                   
                   
                 of the CBEM_response_description element 
               
               
                   
                   
                 should have a corresponding occurrence of the 
               
               
                   
                   
                 CBEM_response_code element. 
               
               
                   
               
            
           
         
       
     
     Table 3 below describes example elements of the CBEM_CBS_Message_Info Segment. 
     
       
         
           
               
             
               
                 TABLE 3 
               
             
            
               
                   
               
               
                 CBEM_CBS_MESSAGE_INFO SEGMENT ELEMENT DESCRIPTION 
               
            
           
           
               
               
               
            
               
                   
                 MANDATORY/ 
                   
               
               
                   
                 OPTIONAL/ 
               
               
                 CBEM ELEMENT 
                 CONDITIONAL 
                 DEFINITION 
               
               
                   
               
               
                 CBEM_CBS_Message_Info 
                 C 
                 Identifies the segment with elements described in 
               
               
                   
                   
                 the following rows of this table. 
               
               
                   
                   
                 (1) Surrounds CBEM_CBS_Message_Info 
               
               
                   
                   
                 segment sub-elements 
               
               
                   
                   
                 (2) Only a single occurrence is permitted within a 
               
               
                   
                   
                 single &lt;CBEM_CBS_Request&gt;. 
               
               
                   
                   
                 (3) Required for a CBEM_message_type of CBS 
               
               
                   
                   
                 Request and CBS Update Request. 
               
               
                 CBEM_CBS_message_id 
                 M 
                 Identifies the Cell Broadcast message id of the 
               
               
                   
                   
                 CBEM message. Code values are defined in 3GPP 
               
               
                   
                   
                 TS 23.041. 
               
               
                 CBEM_data_coding_scheme 
                 M 
                 Identifies the alphabet or coding employed for the 
               
               
                   
                   
                 message characters. 
               
               
                   
                   
                 Code Values: 
               
               
                   
                   
                 “GSM_7_Bit_Coding” - Language using the 
               
               
                   
                   
                 GSM 7 bit default alphabet 
               
               
                 CBEM_language 
                 M 
                 Identifies the language of the information in the 
               
               
                   
                   
                 CBS pages. 
               
               
                   
                   
                 Code Values: 
               
               
                   
                   
                 “English” 
               
               
                   
                   
                 “Spanish” 
               
               
                   
                   
                 “French” 
               
               
                   
                   
                 “German” 
               
               
                   
                   
                 “Italian” 
               
               
                   
                   
                 “Dutch” 
               
               
                   
                   
                 “Swedish” 
               
               
                   
                   
                 “Danish” 
               
               
                   
                   
                 “Portuguese” 
               
               
                   
                   
                 “Finnish” 
               
               
                   
                   
                 “Norwegian” 
               
               
                   
                   
                 “Greek” 
               
               
                   
                   
                 “Turkish” 
               
               
                   
                   
                 “Hungarian” 
               
               
                   
                   
                 “Polish” 
               
               
                   
                   
                 “Czech” 
               
               
                   
                   
                 “Hebrew” 
               
               
                   
                   
                 “Arabic” 
               
               
                   
                   
                 “Russian” 
               
               
                   
                   
                 “Icelandic” 
               
               
                 CBEM_CBS_page 
                 M 
                 Contains the information to be broadcast. 
               
               
                   
                   
                 Information may be split across multiple Cell 
               
               
                   
                   
                 Broadcast Service (CBS) pages of 82 octets 
               
               
                   
                   
                 which is equivalent to 93 7-bit characters. 
               
               
                   
                   
                 Multiple occurrences may occur. 
               
               
                   
                   
                 Minimum of 1 CBS page is required. 
               
               
                   
                   
                 Maximum of 15 CBS pages allowed. 
               
               
                 CBEM_repetition_period 
                 M 
                 This specifies the repetition period for the CBS 
               
               
                   
                   
                 message per 3GPP TS 23.041. 
               
               
                   
                   
                 This indicates the period of time after which 
               
               
                   
                   
                 broadcast of the CBS message should be 
               
               
                   
                   
                 repeated. The minimum period with which a 
               
               
                   
                   
                 CBS message consisting of one CBS page may 
               
               
                   
                   
                 be broadcast over the air interface is a period of 
               
               
                   
                   
                 1.883 s. 
               
               
                   
                   
                 The value of “Repetition-Period” shall be in the 
               
               
                   
                   
                 range 1 to 1024 where each unit will represent 
               
               
                   
                   
                 the value of one minimum period. 
               
               
                 CBEM_number_of_broadcasts_requested 
                 M 
                 This specifies the number of times the CBS message 
               
               
                   
                   
                 is to be broadcast per 3GPP TS 23.041. 
               
               
                   
                   
                 CBEM_number_of_broadcasts_requested may take 
               
               
                   
                   
                 any value up to 65535 (this maximum allows the 
               
               
                   
                   
                 CBS message to be broadcast approximately 
               
               
                   
                   
                 every 1.883 s for more than 24 h). If the 
               
               
                   
                   
                 parameter is set to 0 then the CBS message will 
               
               
                   
                   
                 be broadcast indefinitely (i.e. until the CBC 
               
               
                   
                   
                 receives an appropriate cancel indication). 
               
               
                   
               
            
           
         
       
     
     Table 4 below describes example elements of the CBEM_CBS_Geotargeting_Info Segment. 
     
       
         
           
               
             
               
                 TABLE 4 
               
             
            
               
                   
               
               
                 CBEM_CBS_GEOTARGETING_INFO ELEMENT DESCRIPTION 
               
            
           
           
               
               
               
            
               
                   
                 MANDATORY/ 
                   
               
               
                   
                 OPTIONAL/ 
               
               
                 CBEM ELEMENT 
                 CONDITIONAL 
                 CBEM DEFINITION 
               
               
                   
               
               
                 CBEM_CBS_Geotargeting_Info 
                 C 
                 Identifies the segment with elements described in 
               
               
                   
                   
                 the following rows of this table. 
               
               
                   
                   
                 (1) Surrounds CBEM_CBS_Geotargeting_Info 
               
               
                   
                   
                 segment sub-elements 
               
               
                   
                   
                 (2) Multiple instances are permitted within a 
               
               
                   
                   
                 single &lt;CBEM_CBS_Message_Info&gt;. 
               
               
                   
                   
                 (3) Required for a CBEM_message_type of CBS 
               
               
                   
                   
                 Request and CBS Update. 
               
               
                   
                   
                 (4) At least one of the &lt;CBEM_geocode&gt;, 
               
               
                   
                   
                 &lt;CBEM_polygon&gt;, &lt;CBEM_circle&gt;, or 
               
               
                   
                   
                 &lt;CBEM_gnis&gt; elements must be included. 
               
               
                 CBEM_geocode_type 
                 C 
                 Required if CBEM_geocode element is included. 
               
               
                   
                   
                 Defines the type of encoding for the associated 
               
               
                   
                   
                 CBEM_geocode element. 
               
               
                   
                   
                 Code Values: 
               
               
                   
                   
                 “CMAS” - CMAS geocode 
               
               
                   
                   
                 “SAME” - NOAA National Weather Service 
               
               
                   
                   
                 (NWS) Specific Area Message Encoding 
               
               
                   
                   
                 (SAME) code 
               
               
                   
                   
                 “FIPS” - Federal Information Processing 
               
               
                   
                   
                 Standards (FIPS) code 
               
               
                   
                   
                 “ZIP” - U. S. Postal Service ZIP code 
               
               
                 CBEM_geocode 
                 C 
                 Required if CBEM_geocode_type element is 
               
               
                   
                   
                 included. 
               
               
                   
                   
                 The geographic code delineating the Cell 
               
               
                   
                   
                 Broadcast Area using the encoding type as 
               
               
                   
                   
                 defined in the CBEM_geocode_type element. 
               
               
                   
                   
                 Geocode values for a geocode type of CMAS are 
               
               
                   
                   
                 defined in the Joint ATIS/TIA CMAS Federal 
               
               
                   
                   
                 Alert Gateway to CMSP Gateway Interface 
               
               
                   
                   
                 Specification 
               
               
                   
                   
                 Geocode values for a geocode type of FIPS are 
               
               
                   
                   
                 defined in FIPS Publication 6-4 and is 
               
               
                   
                   
                 available online at 
               
               
                   
                   
                 http://www.itl.nist.gov/fipspubs/index.htm 
               
               
                   
                   
                 Geocode values for a geocode type of SAME are 
               
               
                   
                   
                 defined at 
               
               
                   
                   
                 http://www.nws.noaa.gov/nwr/indexnw.htm#sametable 
               
               
                   
                   
                 Values for a geocode type of ZIP are defined at 
               
               
                   
                   
                 http://zip4.usps.com. 
               
               
                 CBEM_polygon 
                 C 
                 The paired values of points defining a polygon 
               
               
                   
                   
                 that delineates the Cell Broadcast Area. 
               
               
                   
                   
                 Code Values: 
               
               
                   
                   
                 The code values of the geographic polygon are 
               
               
                   
                   
                 represented by a whitespace-delimited list of 
               
               
                   
                   
                 WGS 84 coordinate pairs. 
               
               
                   
                   
                 The first and last pairs of coordinates must be the 
               
               
                   
                   
                 same. 
               
               
                   
                   
                 It is recommended that the maximum number of 
               
               
                   
                   
                 coordinate pairs be limited to 100. 
               
               
                 CBEM_circle 
                 C 
                 The paired values of a point and radius 
               
               
                   
                   
                 delineating the Cell Broadcast Area. 
               
               
                   
                   
                 Code Values: 
               
               
                   
                   
                 The circular area is represented by a central 
               
               
                   
                   
                 point given as a WGS-84 coordinates pair 
               
               
                   
                   
                 followed by a space character and a radius 
               
               
                   
                   
                 value in kilometers. 
               
               
                 CBEM_gnis 
                 C 
                 This value is the geographic code delineating the 
               
               
                   
                   
                 Cell Broadcast Area using the U.S.G.S. 
               
               
                   
                   
                 Geographic Names Information System 
               
               
                   
                   
                 (GNIS) code as defined at 
               
               
                   
                   
                 http://geonames.usgs.gov. 
               
               
                   
               
            
           
         
       
     
     The following is an example XML Schema for messages communicated between the CBE to CBC. 
     
       
         
           
               
             
               
                   
               
             
            
               
                 &lt;?xml version = ″1.0″ encoding = ″UTF-8″?&gt; 
               
               
                 &lt;schema xmlns = ″http://www.w3.org/2001/XMLSchema″ 
               
            
           
           
               
               
            
               
                   
                 targetNamespace = ″cbem:1.0″ 
               
               
                   
                 xmlns:cbem = ″cbem:1.0″ 
               
               
                   
                 xmlns:xs = ″http://www.w3.org/2001/XMLSchema″ 
               
               
                   
                 elementFormDefault = ″qualified″ 
               
               
                   
                 attributeFormDefault = ″unqualified″&gt; 
               
               
                   
                 &lt;element name = ″CBEM_CBS_Request″/&gt; 
               
               
                   
                 &lt;annotation&gt; 
               
               
                   
                  &lt;documentation&gt;CBEM_CBS_Request (version 1.0)&lt;/documentation&gt; 
               
               
                   
                 &lt;/annotation&gt; 
               
               
                   
                 &lt;complexType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;sequence&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;element name = ″CBEM_protocol_version″ type = 
               
            
           
           
               
            
               
                 ″string″/&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;element name = ″CBEM_sender_id” type = ″anyURI″/&gt; 
               
               
                   
                 &lt;element name = ″CBEM_message_number″ type = ″string″/&gt; 
               
               
                   
                 &lt;element name = ″CBEM_referenced_message_number″ type = 
               
            
           
           
               
            
               
                 ″string″ 
               
            
           
           
               
               
            
               
                   
                 minOccurs = “0”/&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;element name = ″CBEM_message_type″&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;simpleType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;restriction base = ″string″&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;enumeration value = ″CBS Request″/&gt; 
               
               
                   
                 &lt;enumeration value = ″CBS Update Request″/&gt; 
               
               
                   
                 &lt;enumeration value = ″CBS Cancel Request″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Ack″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Error″/&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/restriction&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/simpleType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/element&gt; 
               
               
                   
                 &lt;element name = ″CBEM_response_code″ type = ″string″ 
               
            
           
           
               
            
               
                 minOccurs = ″0″ 
               
            
           
           
               
               
            
               
                   
                 maxOccurs = “unbounded”/&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;element name = ″CBEM_response_description″ type = 
               
            
           
           
               
            
               
                 ″string″ minOccurs = ″0″ 
               
            
           
           
               
               
            
               
                   
                 maxOccurs = “unbounded”/&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;element name = ″CBEM_CBC_Message_Info″ minOccurs = ″0″&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;complexType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;sequence&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;element name = ″CBEM_CBS_message_id″ type = 
               
            
           
           
               
            
               
                 ″string″ /&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;element name = ″CBEM_data_coding_scheme″&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;simpleType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;restriction base = ″string″&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;enumeration value = 
               
            
           
           
               
            
               
                 ″GSM 7 Bit Coding″/&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/restriction&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/simpleType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/element&gt; 
               
               
                   
                 &lt;element name = ″CBEM_language″&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;&lt;simpleType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;restriction base = ″string″&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;enumeration value = ″English″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Spanish″/&gt; 
               
               
                   
                 &lt;enumeration value = ″French″/&gt; 
               
               
                   
                 &lt;enumeration value = ″German″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Italian″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Dutch″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Swedish″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Danish″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Portuguese″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Finnish″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Norwegian″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Greek″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Turkish″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Hungarian″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Polish″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Czech″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Hebrew″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Arabic″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Russian″/&gt; 
               
               
                   
                 &lt;enumeration value = ″Icelandic″/&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/restriction&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/simpleType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/element&gt; 
               
               
                   
                 &lt;element name = ″CBEM_CBS_page″ minOccurs = ″1″ 
               
            
           
           
               
            
               
                 maxOccurs = ″15″&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;simpleType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;restriction base = ″string″ length value 
               
            
           
           
               
            
               
                 = ″93″/&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/restriction&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/simpleType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;element name = ″CBEM_repetition_period″ type = 
               
            
           
           
               
            
               
                 ″hexBinary″/&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;element name = 
               
            
           
           
               
            
               
                 ″CBEM_number_of_broadcasts_requested″ 
               
            
           
           
               
               
            
               
                   
                 type = ″hexBinary″/&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;element name = ″CBEM_CBS_Geotargeting_Info″ 
               
            
           
           
               
            
               
                 minOccurs = ″0″ 
               
            
           
           
               
               
            
               
                   
                 maxOccurs = ″unbounded″&gt; 
               
               
                   
                  &lt;complexType&gt; 
               
            
           
           
               
               
            
               
                   
                  &lt;sequence&gt; 
               
            
           
           
               
               
            
               
                   
                  &lt;element name = ″CBEM_geocode_type″&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;&lt;simpleType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;restriction base = ″string″&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;enumeration value = “CMAS″/&gt; 
               
               
                   
                 &lt;enumeration value = ″SAME″/&gt; 
               
               
                   
                 &lt;enumeration value = ″FIPS″/&gt; 
               
               
                   
                 &lt;enumeration value = ″ZIP″/&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/restriction&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/simpleType&gt; 
               
            
           
           
               
               
            
               
                   
                  &lt;/element&gt; 
               
               
                   
                  &lt;element name = ″CBEM_geocode″ type= 
               
            
           
           
               
            
               
                 ″string” 
               
            
           
           
               
               
            
               
                   
                  maxOccurs = ″unbounded″/&gt; 
               
            
           
           
               
               
            
               
                   
                  &lt;element name = ″CBEM_polygon″ type = 
               
            
           
           
               
            
               
                 ″string″ 
               
            
           
           
               
               
            
               
                   
                  minOccurs = ″0″ maxOccurs = 
               
            
           
           
               
            
               
                 ″unbounded″/&gt; 
               
            
           
           
               
               
            
               
                   
                  &lt;element name = ″CBEM_circle″ type = 
               
            
           
           
               
            
               
                 “string″ 
               
            
           
           
               
               
            
               
                   
                  minOccurs = ″0″ maxOccurs = 
               
            
           
           
               
            
               
                 ″unbounded″/&gt; 
               
            
           
           
               
               
            
               
                   
                  &lt;element name = ″CBEM_gnis″ type = 
               
            
           
           
               
            
               
                 “string″ 
               
            
           
           
               
               
            
               
                   
                  minOccurs = ″0″ maxOccurs = 
               
            
           
           
               
            
               
                 ″unbounded″/&gt; 
               
            
           
           
               
               
            
               
                   
                  &lt;/sequence&gt; 
               
            
           
           
               
               
            
               
                   
                  &lt;/complexType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/complexType&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/element&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/sequence&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/complexType&gt; 
               
            
           
           
               
               
            
               
                   
                  &lt;/element&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;element name = ″valueName″ type = ″string″/&gt; 
               
               
                   
                 &lt;element name = ″value″ type = ″string″/&gt; 
               
            
           
           
               
            
               
                 &lt;/schema&gt; 
               
               
                   
               
            
           
         
       
     
     As previously described, the CBC can respond to the CBE. For example, as described with reference to  FIG. 3 , step  24 , the CBC can respond to the CBE with an acknowledgement of a request message. And, as another example, with reference to  FIG. 4 , step  36 , the CBC can respond to the CBE with an error message. Table 5 below describes example response codes and the response descriptions that can be sent by the CBC to the CBE. Message acknowledgement is accomplished with a message type of “Ack” which does not contain the conditional elements for response code and response description. The response codes and associated descriptions listed below are used in the response codes and resources descriptions of the “Error” message type. 
     
       
         
           
               
             
               
                 TABLE 5 
               
             
            
               
                   
               
               
                 DESCRIPTION OF CBE MESSAGE RESPONSE CODES 
               
            
           
           
               
               
               
            
               
                   
                 RESPONSE DESCRIPTION INCLUDED 
                   
               
               
                 RESPONSE 
                 IN CBEM_RESPONSE_DESCRIPTION 
               
               
                 CODE 
                 ELEMENT 
                 NOTES 
               
               
                   
               
               
                 100 
                 invalid-CBE-id 
                 The sending CBE identifier is not valid. 
               
               
                 101 
                 protocol-version-not-supported 
                 The CBC does not support the indicated 
               
               
                   
                   
                 protocol version 
               
               
                 102 
                 server-error 
                 General error in the CBC server 
               
               
                 103 
                 invalid-format 
                 The received XML has an invalid format 
               
               
                 104 
                 invalid-element XXX 
                 XXX replaced with the name of the invalid 
               
               
                   
                   
                 element 
               
               
                 105 
                 missing-element XXX 
                 XXX replaced with name of missing element 
               
               
                 106 
                 operation-not-allowed 
                 The requested operation is not allowed 
               
               
                 107 
                 missing-geo-targeting-area 
                 No geo-targeting information element 
               
               
                   
                   
                 provided in the CBEM geo-targeting 
               
               
                   
                   
                 segment 
               
               
                   
               
            
           
         
       
     
     As previously described, with reference to  FIG. 3 , step  20 , and  FIG. 4 , step  32 , as part of the communication between the CBE and the CBC, the CBE can send request messages to the CBC. Example request messages include an initial request message, an update request message, and a cancel request message. In an example embodiment, a CBE to CBC Initial Request Message comprises a CBE message containing one CBEM_CBS_Request segment, one CBEM_CBS_Message_Info segment, and one or more CBEM_CBS_Geotargeting_Info segments. Table 6 below contains a description of example CBE message elements of the CBEM_CBS_Request segment for an initial request message from the CBE to the CBC: 
     
       
         
           
               
             
               
                 TABLE 6 
               
             
            
               
                   
               
               
                 ELEMENTS OF CBEM_CBS_REQUEST SEGMENT FOR INITIAL 
               
               
                 REQUEST MESSAGE 
               
            
           
           
               
               
               
            
               
                   
                 CBEM ELEMENT 
                 VALUE 
               
               
                   
                   
               
               
                   
                 CBEM_protocol_version 
                 Per Table 2 
               
               
                   
                 CBEM_sender_id 
                 Identifies the CBE which initiated 
               
               
                   
                   
                 the CBEM message. 
               
               
                   
                 CBEM_message_number 
                 Per Table 2 
               
               
                   
                 CBEM_message_type 
                 Value of “CBS Request”. 
               
               
                   
                   
               
            
           
         
       
     
     Table 7 below contains a description of example CBE message elements of the CBEM_CBS_Message_Info segment for an initial request message from the CBE to the CBC. 
     
       
         
           
               
             
               
                 TABLE 7 
               
             
            
               
                   
               
               
                 ELEMENTS OF CBEM_CBS_MESSAGE_INFO SEGMENT 
               
               
                 FOR INITIAL REQUEST MESSAGE 
               
            
           
           
               
               
               
            
               
                   
                 CBEM ELEMENT 
                 VALUE 
               
               
                   
                   
               
               
                   
                 CBEM_CBS_message_id 
                 Per Table 3 
               
               
                   
                 CBEM_data_coding_scheme 
                 Per Table 3 
               
               
                   
                 CBEM_language 
                 Per Table 3 
               
               
                   
                 CBEM_CBS_page 
                 Per Table 3 
               
               
                   
                 CBEM_repetition_period 
                 Per Table 3 
               
               
                   
                 CBEM_number_of_broadcasts_requested 
                 Per Table 3 
               
               
                   
                   
               
            
           
         
       
     
     Table 8 below contains a description of example CBE message elements of the CBEM_CBS_Geotargeting_Info segment for an initial request message from the CBE to the CBC. Note that the values listed in Table 8 refer to corresponding CBEM Definition sections of Table 4. 
     
       
         
           
               
             
               
                 TABLE 8 
               
             
            
               
                   
               
               
                 ELEMENTS OF CBEM_CBS_GEOTARGETING_INFO 
               
               
                 SEGMENT FOR INITIAL REQUEST MESSAGE 
               
            
           
           
               
               
               
            
               
                   
                 CBEM ELEMENT 
                 VALUE 
               
               
                   
                   
               
               
                   
                 CBEM_geocode_type 
                 Per Table 4 
               
               
                   
                 CBEM_geocode 
                 Per Table 4 
               
               
                   
                 CBEM_polygon 
                 Per Table 4 
               
               
                   
                 CBEM_circle 
                 Per Table 4 
               
               
                   
                 CBEM_gnis 
                 Per Table 4 
               
               
                   
                   
               
            
           
         
       
     
     The following is an example CMAS initial request message from the CBE to the CBC in XML format: 
     
       
         
           
               
             
               
                   
               
             
            
               
                 &lt;?xml version = “1.0” encoding = “UTF-8”?&gt; 
               
               
                 &lt;CMA_CBS_Request xmlns = “urn:xxx:xxx:xx:xxx:cbem:1.0”&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_protocol_version&gt;1.0&lt;/CBEM_protocol_version&gt; 
               
               
                   
                 &lt;CBEM_sender_id&gt;http://at_cmsp_gateway.com&lt;/CBEM_sender_id&gt; 
               
               
                   
                 &lt;CBEM_message_number&gt;ATT-CMSP-Gateway-2008- 
               
            
           
           
               
            
               
                 1056&lt;/CBEM_message_number&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_message_type&gt;CBS Request&lt;/CBEM_message_type&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_CBS_Message_Info&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_CBS_message_id&gt;4373&lt;/CBEM_CBS_message_id&gt; 
               
               
                   
                 &lt;CBEM_data_coding_scheme&gt;GSM_7_Bit_Coding&lt;/CBEM —   
               
            
           
           
               
            
               
                 data_coding_scheme&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_language&gt;English&lt;/CBEM_ language&gt; 
               
               
                   
                 &lt;CBEM_CBS_page&gt;Severe Weather Warning in this area until 
               
            
           
           
               
            
               
                 4:15pm MST NWS&lt;/CBEM_ CBS_page&gt; 
               
            
           
           
               
               
            
               
                   
                  &lt;CBEM_repetition_period&gt;500&lt;/CBEM_repetition_period&gt; 
               
            
           
           
               
            
               
                 &lt;CBEM_number_of_broadcasts_requested&gt;50&lt;/CBEM_number_of_broadcasts_r 
               
               
                 equested&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_CBS_Geotargeting_Info&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_geocode_type&gt;CMAS&lt;/CBEM_geocode_type&gt; 
               
               
                   
                 &lt;CBEM_geocode&gt;004005&lt;/CBEM_geocode&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/CBEM_CBS_Geotargeting_Info&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/CBEM_CBC_Message_Info&gt; 
               
            
           
           
               
            
               
                 &lt;/CBEM_CBS_Request&gt; 
               
               
                   
               
            
           
         
       
     
     In an example embodiment, a CBE to CBC update request message comprises a CBEM message containing one CBEM_CBS_Request segment, one CBEM_CBS_Message_Info segment, and one or more CBEM_CBS_Geotargeting_Info segments. Table 9 below contains a summary of example CBEM elements of the CBEM_CBS_Request segment for an update request message from the CBEM to the CBC: 
     
       
         
           
               
             
               
                 TABLE 9 
               
             
            
               
                   
               
               
                 ELEMENTS OF CBEM_CBS_REQUEST SEGMENT 
               
               
                 FOR UPDATE REQUEST MESSAGE 
               
            
           
           
               
               
            
               
                 CBEM ELEMENT 
                 VALUE 
               
               
                   
               
               
                 CBEM_protocol_version 
                 Per Table 2 
               
               
                 CBEM_sender_id 
                 Identifies the CBE which 
               
               
                   
                 initiated the CBEM message. 
               
               
                 CBEM_message_number 
                 Per Table 2 
               
               
                 CBEM_referenced_message_number 
                 Per Table 2 
               
               
                 CBEM_message_type 
                 Value of “CBS Update 
               
               
                   
                 Request”. 
               
               
                   
               
            
           
         
       
     
     Table 10 below describes example CBEM elements of the CBEM_CBS_Message_Info segment for an update request message from the CBE to the CBC. 
     
       
         
           
               
             
               
                 TABLE 10 
               
             
            
               
                   
               
               
                 ELEMENTS OF CBEM_CBS_MESSAGE_INFO 
               
               
                 SEGMENT FOR UPDATE REQUEST MESSAGE 
               
            
           
           
               
               
               
            
               
                   
                 CBEM ELEMENT 
                 VALUE 
               
               
                   
                   
               
               
                   
                 CBEM_CBS_message_id 
                 Per Table 3 
               
               
                   
                 CBEM_data_coding_scheme 
                 Per Table 3 
               
               
                   
                 CBEM_language 
                 Per Table 3 
               
               
                   
                 CBEM_CBS_page 
                 Per Table 3 
               
               
                   
                 CBEM_repetition_period 
                 Per Table 3 
               
               
                   
                 CBEM_number_of_broadcasts_requested 
                 Per Table 3 
               
               
                   
                   
               
            
           
         
       
     
     Table 11 below describes example CBE message elements of the CBEM_CBS_Geotargeting_Info segment for an update request message from the CBE to the CBC. 
     
       
         
           
               
             
               
                 TABLE 11 
               
             
            
               
                   
               
               
                 ELEMENTS OF CBEM_CBS_GEOTARGETING_INFO 
               
               
                 SEGMENT FOR UPDATE REQUEST MESSAGE 
               
            
           
           
               
               
               
            
               
                   
                 CBEM ELEMENT 
                 VALUE 
               
               
                   
                   
               
               
                   
                 CBEM_geocode_type 
                 Per Table 4 
               
               
                   
                 CBEM_geocode 
                 Per Table 4 
               
               
                   
                 CBEM_polygon 
                 Per Table 4 
               
               
                   
                 CBEM_circle 
                 Per Table 4 
               
               
                   
                 CBEM_gnis 
                 Per Table 4 
               
               
                   
                   
               
            
           
         
       
     
     The following is an example CMAS update message from the CBE to the CBC in XML format. 
     
       
         
           
               
             
               
                   
               
             
            
               
                 &lt;?xml version = “1.0” encoding = “UTF-8”?&gt; 
               
               
                 &lt;CMA_CBS_Request_xmlns = “urn:xxx:xxx:xx:xxx:cmad:1.0”&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_protocol_version&gt;1.0&lt;/CBEM_protocol_version&gt; 
               
               
                   
                 &lt;CBEM_message_number&gt;ATT-CMSP-Gateway-2008- 
               
            
           
           
               
            
               
                 1087&lt;/CBEM_message_number&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_referenced_message_number&gt;ATT-CMSP-Gateway-2008- 
               
            
           
           
               
            
               
                 1056&lt;/CBEM_referenced_message —   
               
               
                 number&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_sender_id&gt;http://att_cmsp_gateway.com&lt;/CBEM_sender_id&gt; 
               
               
                   
                 &lt;CBEM_message_type&gt;CBS Update Request&lt;/CBEM_message_type&gt; 
               
               
                   
                 &lt;CBEM_CBS_Message_Info&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_CBS_message_id&gt;4373&lt;/CBEM_CBS_message_id&gt; 
               
               
                   
                 &lt;CBEM_data_coding_scheme&gt;GSM_7_Bit_Coding&lt;/CBEM —   
               
            
           
           
               
            
               
                 data_coding_scheme&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_language&gt;English&lt;/CBEM_ language&gt; 
               
               
                   
                 &lt;CBEM_CBS_page&gt;Severe Weather Warning in this area until 
               
            
           
           
               
            
               
                 7:15pm MST NWS&lt;/ CBEM_ CBS_page&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_repetition_period&gt;500&lt;/CBEM_repetition_period&gt; 
               
            
           
           
               
            
               
                 &lt;CBEM_number_of_broadcasts_requested&gt;50&lt;/CBEM_number_of_broadcasts_r 
               
               
                 equested&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_CBS_Geotargeting_Info&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_geocode_type&gt;CMAS&lt;/CBEM_geocode_type&gt; 
               
               
                   
                 &lt;CBEM_geocode&gt;004005&lt;/CBEM_geocode&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/CBEM_CBS_Geotargeting_Info&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;/CBEM_CBC_Message_Info&gt; 
               
            
           
           
               
            
               
                 &lt;/CBEM_CBS_Request&gt; 
               
               
                   
               
            
           
         
       
     
     In an example embodiment, a CBE to CBC cancel message comprises a CBE message containing one CBEM_CBS_Request segment. Table 12 below describes example CBEM elements of the CBEM_CBS_Request segment. 
     
       
         
           
               
             
               
                 TABLE 12 
               
             
            
               
                   
               
               
                 ELEMENTS OF CBEM_CBS_REQUEST SEGMENT FOR CANCEL 
               
               
                 MESSAGE 
               
            
           
           
               
               
            
               
                 CBEM ELEMENT 
                 VALUE 
               
               
                   
               
               
                 CBEM_protocol_version 
                 Per Table 2 
               
               
                 CBEM_sender_id 
                 Identifies the CBE which 
               
               
                   
                 initiated the CBEM message. 
               
               
                 CBEM_message_number 
                 Per Table 2 
               
               
                 CBEM_referenced_message_number 
                 Per Table 2 
               
               
                 CBEM_message_type 
                 Value of “CBS Cancel”. 
               
               
                   
               
            
           
         
       
     
     The following is an example CMAS cancellation message from the CBE to the CBC in XML format: 
     
       
         
           
               
             
               
                   
               
             
            
               
                 &lt;?xml version = “1.0” encoding = “UTF-8”?&gt; 
               
               
                 &lt;CMA_CBS_Request xmlns = “urn:xxx:xxx:xx:xxx:cmad:1.0”&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_protocol version&gt;1.0&lt;/CBEM_protocol_version&gt; 
               
               
                   
                 &lt;CBEM_sender_id&gt;http://att_cmsp_gateway.com&lt;/CBEM_sender_id&gt; 
               
               
                   
                 &lt;CBEM_message_type&gt;CBS Cancel&lt;/CBEM_message_type&gt; 
               
               
                   
                 &lt;CBEM_message_number&gt;ATT-CMSP-Gateway-2008-1087&lt;/CBEM_message_number&gt; 
               
               
                   
                 &lt;CBEM_referenced_message_number&gt;ATT-CMSP-Gateway-2008- 
               
            
           
           
               
            
               
                 1056&lt;/CBEM_referenced_message —   
               
               
                 number&gt; 
               
               
                 &lt;/CBEM_CBS_Request&gt; 
               
               
                   
               
            
           
         
       
     
     In an example embodiment, an acknowledgement message sent from the CBC to the CBE comprises a CBEM message containing one CBEM_CBS_Request segment. Table 13 below describes example CBE message elements of the CBEM_CBS_Request segment. 
     
       
         
           
               
             
               
                 TABLE 13 
               
             
            
               
                   
               
               
                 ELEMENTS OF CBEM_CBS_REQUEST SEGMENT FOR 
               
               
                 ACKNOWLEDGEMENT RESPONSE MESSAGE 
               
            
           
           
               
               
            
               
                 CBEM ELEMENT 
                 VALUE 
               
               
                   
               
               
                 CBEM_protocol_version 
                 Per Table 2 
               
               
                 CBEM_sender_id 
                 Identifies the CBE which 
               
               
                   
                 initiated the CBEM message. 
               
               
                 CBEM_message_number 
                 Per Table 2 
               
               
                 CBEM_referenced_message_number 
                 Per Table 2 
               
               
                 CBEM_message_type 
                 Value of “Ack”. 
               
               
                   
               
            
           
         
       
     
     The following is an example CMAS acknowledgement response message from the CBC to the CBE in XML format: 
     
       
         
           
               
             
               
                   
               
             
            
               
                 &lt;?xml version = “1.0” encoding = “UTF-8”?&gt; 
               
               
                 &lt;CMA_CBS_Request xmlns = “urn:xxx:xxx:xx:xxx:cbem:1.0”&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_protocol_version&gt;1.0&lt;/CBEM_protocol_version&gt; 
               
            
           
           
               
            
               
                 &lt;CBEM_sender_id&gt;http://att_cell_broadcast_center.com&lt;/CBEM_sen 
               
               
                 der_id&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_message_type&gt;Ack&lt;/CBEM_message_type&gt; 
               
               
                   
                 &lt;CBEM_message_number&gt;ATT-CBC-2008- 
               
            
           
           
               
            
               
                 1095&lt;/CBEM_message_number&gt; 
               
               
                 &lt;/CBEM_CBS_Request&gt; 
               
               
                   
               
            
           
         
       
     
     In an example embodiment, an error response message sent from the CBC to the CBE comprises a CBEM message containing one CBEM_CBS_Request segment. Table 14 below describes example CBE message elements of the CBEM_CBS_Request segment. 
     
       
         
           
               
             
               
                 TABLE 14 
               
             
            
               
                   
               
               
                 ELEMENTS OF CBEM_CBS_REQUEST SEGMENT FOR ERROR 
               
               
                 RESPONSE MESSAGE 
               
            
           
           
               
               
            
               
                 CBEM ELEMENT 
                 VALUE 
               
               
                   
               
               
                 CBEM_protocol_version 
                 Per Table 2 
               
               
                 CBEM_sender_id 
                 Identifies the CBE which 
               
               
                   
                 initiated the CBEM message. 
               
               
                 CBEM_message_number 
                 Per Table 2 
               
               
                 CBEM_referenced_message_number 
                 Per Table 2 
               
               
                 CBEM_message_type 
                 Value of “Error”. 
               
               
                 CBEM_response_code 
                 Per Table 5 
               
               
                 CBEM_response_description 
                 Per Table 5 
               
               
                   
               
            
           
         
       
     
     The following is an example CMAS error response message from the CBC to the CBE in XML format: 
     
       
         
           
               
             
               
                   
               
             
            
               
                 &lt;?xml version = “1.0” encoding = “UTF-8”?&gt; 
               
               
                 &lt;CMA_CBS_Request xmlns = “urn:xxx:xxx:xx:xxx:cmad:1.0”&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_protocol_version&gt;1.0&lt;/CBEM_protocol_version&gt; 
               
            
           
           
               
            
               
                 &lt;CBEM_sender_id&gt;http://att_cell_broadcast_center.com&lt;/CBEM_sender_id 
               
               
                 &gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_message_type&gt;Error&lt;/CBEM_message_type&gt; 
               
               
                   
                 &lt;CBEM_message number&gt;ATT-CMSP-Gateway-2008- 
               
            
           
           
               
            
               
                 1097&lt;/CBEM_message_number&gt; 
               
            
           
           
               
               
            
               
                   
                 &lt;CBEM_response_code&gt;103&lt;/CBEM_response_code&gt; 
               
               
                   
                 &lt;CBEM_response_description&gt;invalid- 
               
            
           
           
               
            
               
                 format&lt;/CBEM_response_description&gt; 
               
               
                 &lt;/CBEM_CBS_Request&gt; 
               
               
                   
               
            
           
         
       
     
       FIG. 6  depicts an overall block diagram of an exemplary packet-based mobile cellular network environment, such as a GPRS network, in which communications between a CBE  12  and a CBC  14  in accordance with the above-described XLM-based protocol can be implemented. In such an environment, there are a plurality of Base Station Subsystems (“BSS”)  600  (only one is shown), each of which comprises a Base Station Controller (“BSC”)  602  serving a plurality of Base Transceiver Stations (“BTS”) such as BTSs  604 ,  606 , and  608 . As depicted in  FIG. 6 , the CBE  12  is in communications with the CBC  14  utilizing the above-described XML-based protocol. The CBC  14  is in communications with the BSS  600 . In an example embodiment, the interface between the CBC and BTS is a command and response interface, in which the CBC provides cell broadcast information to the BTS via a WRITE-REPLACE operation with the BTS providing responses that indicate the results of the requested Cell Broadcast operations. BTSs  604 ,  606 ,  608 , etc. are the access points where users of packet-based mobile devices become connected to the wireless network. In exemplary fashion, the packet traffic originating from user devices is transported via an over-the-air interface to a BTS  608 , and from the BTS  608  to the BSC  602 . Base station subsystems, such as BSS  600 , are a part of internal frame relay network  610  that can include Service GPRS Support Nodes (“SGSN”) such as SGSN  612  and  614 . Each SGSN is connected to an internal packet network  620  through which a SGSN  612 ,  614 , etc. can route data packets to and from a plurality of gateway GPRS support nodes (GGSN)  622 ,  624 ,  626 , etc. As illustrated, SGSN  614  and GGSNs  622 ,  624 , and  626  are part of internal packet network  620 . Gateway GPRS serving nodes  622 ,  624  and  626  mainly provide an interface to external Internet Protocol (“IP”) networks such as Public Land Mobile Network (“PLMN”)  650 , corporate intranets  640 , or Fixed-End System (“FES”) or the public Internet  630 . As illustrated, subscriber corporate network  640  may be connected to GGSN  624  via firewall  632 ; and PLMN  650  is connected to GGSN  624  via boarder gateway router  634 . The Remote Authentication Dial-In User Service (“RADIUS”) server  642  may be used for caller authentication when a user of a mobile cellular device calls corporate network  640 . 
     Generally, there can be a several cell sizes in a GSM network, referred to as macro, micro, pico, femto and umbrella cells. The coverage area of each cell is different in different environments. Macro cells can be regarded as cells in which the base station antenna is installed in a mast or a building above average roof top level. Micro cells are cells whose antenna height is under average roof top level. Micro-cells are typically used in urban areas. Pico cells are small cells having a diameter of a few dozen meters. Pico cells are used mainly indoors. Femto cells have the same size as pico cells, but a smaller transport capacity. Femto cells are used indoors, in residential, or small business environments. On the other hand, umbrella cells are used to cover shadowed regions of smaller cells and fill in gaps in coverage between those cells. 
       FIG. 7  illustrates an architecture of a typical GPRS network in which communications between a CBE  12  and a CBC  14  in accordance with the above-described XLM-based protocol can be implemented. The architecture depicted in  FIG. 7  is segmented into four groups: users  750 , radio access network  760 , core network  770 , and interconnect network  780 . Users  750  comprise a plurality of end users. Note, device  712  is referred to as a mobile subscriber in the description of network shown in  FIG. 7 . In an example embodiment, the device depicted as mobile subscriber  712  comprises a mobile device. Radio access network  760  comprises a plurality of base station subsystems such as BSSs  762 , which include BTSs  764  and BSCs  766 . In an example embodiment, the interface between the CBC and BTS is a command and response interface, in which the CBC provides cell broadcast information to the BTS via a WRITE-REPLACE operation with the BTS providing responses that indicate the results of the requested Cell Broadcast operations. Core network  770  comprises a host of various network elements. As illustrated here, core network  770  may comprise Mobile Switching Center (“MSC”)  771 , Service Control Point (“SCP”)  772 , gateway MSC  773 , SGSN  776 , Home Location Register (“HLR”)  774 , Authentication Center (“AuC”)  775 , Domain Name Server (“DNS”)  777 , and GGSN  778 . Interconnect network  780  also comprises a host of various networks and other network elements. As illustrated in  FIG. 7 , interconnect network  780  comprises Public Switched Telephone Network (“PSTN”)  782 , Fixed-End System (“FES”) or Internet  784 , firewall  788 , and Corporate Network  789 . 
     A mobile switching center can be connected to a large number of base station controllers. At MSC  771 , for instance, depending on the type of traffic, the traffic may be separated in that voice may be sent to Public Switched Telephone Network (“PSTN”)  782  through Gateway MSC (“GMSC”)  773 , and/or data may be sent to SGSN  776 , which then sends the data traffic to GGSN  778  for further forwarding. 
     When MSC  771  receives call traffic, for example, from BSC  766 , it sends a query to a database hosted by SCP  772 . The SCP  772  processes the request and issues a response to MSC  771  so that it may continue call processing as appropriate. 
     The HLR  774  is a centralized database for users to register to the GPRS network. HLR  774  stores static information about the subscribers such as the International Mobile Subscriber Identity (“IMSI”), subscribed services, and a key for authenticating the subscriber. HLR  774  also stores dynamic subscriber information such as the current location of the mobile subscriber. Associated with HLR  774  is AuC  775 . AuC  775  is a database that contains the algorithms for authenticating subscribers and includes the associated keys for encryption to safeguard the user input for authentication. 
     In the following, depending on context, the term “mobile subscriber” sometimes refers to the end user and sometimes to the actual portable device, such as a mobile device, used by an end user of the mobile cellular service. When a mobile subscriber turns on his or her mobile device, the mobile device goes through an attach process by which the mobile device attaches to an SGSN of the GPRS network. In  FIG. 7 , when mobile subscriber  712  initiates the attach process by turning on the network capabilities of the mobile device, an attach request is sent by mobile subscriber  712  to SGSN  776 . The SGSN  776  queries another SGSN, to which mobile subscriber  712  was attached before, for the identity of mobile subscriber  712 . Upon receiving the identity of mobile subscriber  712  from the other SGSN, SGSN  776  requests more information from mobile subscriber  712 . This information is used to authenticate mobile subscriber  712  to SGSN  776  by HLR  774 . Once verified, SGSN  776  sends a location update to HLR  774  indicating the change of location to a new SGSN, in this case SGSN  776 . HLR  774  notifies the old SGSN, to which mobile subscriber  712  was attached before, to cancel the location process for mobile subscriber  712 . HLR  774  then notifies SGSN  776  that the location update has been performed. At this time, SGSN  776  sends an Attach Accept message to mobile subscriber  712 , which in turn sends an Attach Complete message to SGSN  776 . 
     After attaching itself with the network, mobile subscriber  712  then goes through the authentication process. In the authentication process, SGSN  776  sends the authentication information to HLR  774 , which sends information back to SGSN  776  based on the user profile that was part of the user&#39;s initial setup. The SGSN  776  then sends a request for authentication and ciphering to mobile subscriber  712 . The mobile subscriber  712  uses an algorithm to send the user identification (ID) and password to SGSN  776 . The SGSN  776  uses the same algorithm and compares the result. If a match occurs, SGSN  776  authenticates mobile subscriber  712 . 
     Next, the mobile subscriber  712  establishes a user session with the destination network, corporate network  789 , by going through a Packet Data Protocol (“PDP”) activation process. Briefly, in the process, mobile subscriber  712  requests access to the Access Point Name (“APN”), for example, UPS.com, and SGSN  776  receives the activation request from mobile subscriber  712 . SGSN  776  then initiates a Domain Name Service (“DNS”) query to learn which GGSN node has access to the UPS.com APN. The DNS query is sent to the DNS server within the core network  770 , such as DNS  777 , which is provisioned to map to one or more GGSN nodes in the core network  770 . Based on the APN, the mapped GGSN  778  can access the requested corporate network  789 . The SGSN  776  then sends to GGSN  778  a Create Packet Data Protocol (“PDP”) Context Request message that contains necessary information. The GGSN  778  sends a Create PDP Context Response message to SGSN  776 , which then sends an Activate PDP Context Accept message to mobile subscriber  712 . 
     Once activated, data packets of the call made by mobile subscriber  712  can then go through radio access network  760 , core network  770 , and interconnect network  780 , in a particular fixed-end system or Internet  784  and firewall  788 , to reach corporate network  789 . 
       FIG. 8  illustrates an exemplary block diagram view of a GSM/GPRS/IP multimedia network architecture  800  within which communications between a CBE  12  and a CBC  14  in accordance with the above-described XLM-based protocol can be implemented. In an example embodiment the CBC is responsible for the determination of the cell sites associated with the indicated target area and for the distribution of Cell Broadcast messages to the calculated set of cell sites within the indicated target area. The CBE is the source of the information to be broadcast to an indicated target area. The CBE could be an Emergency Alert Gateway or any other appropriate information source, such as, for example, stock quotes, sports scores, weather, traffic, etc. As illustrated, architecture  800  of  FIG. 8  includes a GSM core network  801 , a GPRS network  830  and an IP multimedia network  838 . The GSM core network  801  includes a Mobile Station (MS)  802 , at least one Base Transceiver Station (BTS)  804  and a Base Station Controller (BSC)  806 . The MS  802  is physical equipment or Mobile Equipment (ME), such as a mobile phone or a laptop computer that is used by mobile subscribers, with a Subscriber identity Module (SIM) or a Universal Integrated Circuit Card (UICC). The SIM or UICC includes an International Mobile Subscriber Identity (IMSI), which is a unique identifier of a subscriber. The BTS  804  is physical equipment, such as a radio tower, that enables a radio interface to communicate with the MS. Each BTS may serve more than one MS. The BSC  806  manages radio resources, including the BTS. The BSC may be connected to several BTSs. The BSC and BTS components, in combination, are generally referred to as a base station (BSS) or radio access network (RAN)  803 . 
     The GSM core network  801  also includes a Mobile Switching Center (MSC)  808 , a Gateway Mobile Switching Center (GMSC)  810 , a Home Location Register (HLR)  812 , Visitor Location Register (VLR)  814 , an Authentication Center (AuC)  818 , and an Equipment Identity Register (EIR)  816 . The MSC  808  performs a switching function for the network. The MSC also performs other functions, such as registration, authentication, location updating, handovers, and call routing. The GMSC  810  provides a gateway between the GSM network and other networks, such as an Integrated Services Digital Network (ISDN) or Public Switched Telephone Networks (PSTNs)  820 . Thus, the GMSC  810  provides interworking functionality with external networks. 
     The HLR  812  is a database that contains administrative information regarding each subscriber registered in a corresponding GSM network. The HLR  812  also contains the current location of each MS. The VLR  814  is a database that contains selected administrative information from the HLR  812 . The VLR contains information necessary for call control and provision of subscribed services for each MS currently located in a geographical area controlled by the VLR. The HLR  812  and the VLR  814 , together with the MSC  808 , provide the call routing and roaming capabilities of GSM. The AuC  816  provides the parameters needed for authentication and encryption functions. Such parameters allow verification of a subscriber&#39;s identity. The EIR  818  stores security-sensitive information about the mobile equipment. 
     A Short Message Service Center (SMSC)  809  allows one-to-one Short Message Service (SMS) messages to be sent to/from the MS  802 . A Push Proxy Gateway (PPG)  811  is used to “push” (i.e., send without a synchronous request) content to the MS  802 . The PPG  811  acts as a proxy between wired and wireless networks to facilitate pushing of data to the MS  802 . A Short Message Peer to Peer (SMPP) protocol router  813  is provided to convert SMS-based SMPP messages to cell broadcast messages. SMPP is a protocol for exchanging SMS messages between SMS peer entities such as short message service centers. The SMPP protocol is often used to allow third parties, e.g., content suppliers such as news organizations, to submit bulk messages. 
     To gain access to GSM services, such as speech, data, and short message service (SMS), the MS first registers with the network to indicate its current location by performing a location update and IMSI attach procedure. The MS  802  sends a location update including its current location information to the MSC/VLR, via the BTS  804  and the BSC  806 . The location information is then sent to the MS&#39;s HLR. The HLR is updated with the location information received from the MSC/VLR. The location update also is performed when the MS moves to a new location area. Typically, the location update is periodically performed to update the database as location updating events occur. 
     The GPRS network  830  is logically implemented on the GSM core network architecture by introducing two packet-switching network nodes, a serving GPRS support node (SGSN)  832 , a cell broadcast and a Gateway GPRS support node (GGSN)  834 . The SGSN  832  is at the same hierarchical level as the MSC  808  in the GSM network. The SGSN controls the connection between the GPRS network and the MS  802 . The SGSN also keeps track of individual MS&#39;s locations and security functions and access controls. 
     A Cell Broadcast Center (CBC)  14  communicates cell broadcast messages that are typically delivered to multiple users in a specified area. Cell Broadcast is one-to-many geographically focused service. It enables messages to be communicated to multiple mobile phone customers who are located within a given part of its network coverage area at the time the message is broadcast. 
     The GGSN  834  provides a gateway between the GPRS network and a public packet network (PDN) or other IP networks  836 . That is, the GGSN provides interworking functionality with external networks, and sets up a logical link to the MS through the SGSN. When packet-switched data leaves the GPRS network, it is transferred to an external TCP-IP network  836 , such as an X.25 network or the Internet. In order to access GPRS services, the MS first attaches itself to the GPRS network by performing an attach procedure. The MS then activates a packet data protocol (PDP) context, thus activating a packet communication session between the MS, the SGSN, and the GGSN. 
     In a GSM/GPRS network, GPRS services and GSM services can be used in parallel. The MS can operate in one of three classes: class A, class B, and class C. A class A MS can attach to the network for both GPRS services and GSM services simultaneously. A class A MS also supports simultaneous operation of GPRS services and GSM services. For example, class A mobiles can receive GSM voice/data/SMS calls and GPRS data calls at the same time. 
     A class B MS can attach to the network for both GPRS services and GSM services simultaneously. However, a class B MS does not support simultaneous operation of the GPRS services and GSM services. That is, a class B MS can only use one of the two services at a given time. 
     A class C MS can attach for only one of the GPRS services and GSM services at a time. Simultaneous attachment and operation of GPRS services and GSM services is not possible with a class C MS. 
     A GPRS network  630  can be designed to operate in three network operation modes (NOM1, NOM2 and NOM3). A network operation mode of a GPRS network is indicated by a parameter in system information messages transmitted within a cell. The system information messages dictates a MS where to listen for paging messages and how to signal towards the network. The network operation mode represents the capabilities of the GPRS network. In a NOM1 network, a MS can receive pages from a circuit switched domain (voice call) when engaged in a data call. The MS can suspend the data call or take both simultaneously, depending on the ability of the MS. In a NOM2 network, a MS may not received pages from a circuit switched domain when engaged in a data call, since the MS is receiving data and is not listening to a paging channel In a NOM3 network, a MS can monitor pages for a circuit switched network while received data and vise versa. 
     The IP multimedia network  638  was introduced with 3GPP Release 5, and includes an IP multimedia subsystem (IMS)  640  to provide rich multimedia services to end users. A representative set of the network entities within the IMS  640  are a call/session control function (CSCF), a media gateway control function (MGCF)  646 , a media gateway (MGW)  648 , and a master subscriber database, called a home subscriber server (HSS)  650 . The HSS  650  may be common to the GSM network  601 , the GPRS network  630  as well as the IP multimedia network  638 . 
     The IP multimedia system  640  is built around the call/session control function, of which there are three types: an interrogating CSCF (I-CSCF)  643 , a proxy CSCF (P-CSCF)  642 , and a serving CSCF (S-CSCF)  644 . The P-CSCF  642  is the MS&#39;s first point of contact with the IMS  640 . The P-CSCF  642  forwards session initiation protocol (SIP) messages received from the MS to an SIP server in a home network (and vice versa) of the MS. The P-CSCF  642  may also modify an outgoing request according to a set of rules defined by the network operator (for example, address analysis and potential modification). 
     The I-CSCF  643 , forms an entrance to a home network and hides the inner topology of the home network from other networks and provides flexibility for selecting an S-CSCF. The I-CSCF  643  may contact a subscriber location function (SLF)  645  to determine which HSS  650  to use for the particular subscriber, if multiple HSS&#39;s  650  are present. The S-CSCF  644  performs the session control services for the MS  602 . This includes routing originating sessions to external networks and routing terminating sessions to visited networks. The S-CSCF  644  also decides whether an application server (AS)  652  is required to receive information on an incoming SIP session request to ensure appropriate service handling. This decision is based on information received from the HSS  650  (or other sources, such as an application server  652 ). The AS  652  also communicates to a location server  656  (e.g., a Gateway Mobile Location Center (GMLC)) that provides a position (e.g., latitude/longitude coordinates) of the MS  602 . 
     The HSS  650  contains a subscriber profile and keeps track of which core network node is currently handling the subscriber. It also supports subscriber authentication and authorization functions (AAA). In networks with more than one HSS  650 , a subscriber location function provides information on the HSS  650  that contains the profile of a given subscriber. 
     The MGCF  646  provides interworking functionality between SIP session control signaling from the IMS  640  and ISUP/BICC call control signaling from the external GSTN networks (not shown). It also controls the media gateway (MGW)  648  that provides user-plane interworking functionality (e.g., converting between AMR- and PCM-coded voice). The MGW  648  also communicates with other IP multimedia networks  654 . 
     Push to Talk over Cellular (PoC) capable mobile phones register with the wireless network when the phones are in a predefined area (e.g., job site, etc.). When the mobile phones leave the area, they register with the network in their new location as being outside the predefined area. This registration, however, does not indicate the actual physical location of the mobile phones outside the pre-defined area. 
     While example embodiments of and XML-based protocol for communications between a CBE and a CBC have been described in connection with various computing devices/processor, the underlying concepts can be applied to any computing device, processor, or system capable of utilizing and/or implementing an XML-based protocol for communications between a CBE and a CBC. The various techniques described herein can be implemented in connection with hardware or software or, where appropriate, with a combination of both. Thus, the methods and apparatuses for the utilization an XML-based protocol for communications between a CBE and a CBC, or certain aspects or portions thereof, can take the form of program code (i.e., instructions) embodied in tangible storage media, such as floppy diskettes, CD-ROMs, hard drives, or any other machine-readable storage medium, wherein, when the program code is loaded into and executed by a machine, such as a computer, the machine becomes an apparatus for the utilization of an XML-based protocol for communications between a CBE and a CBC. In the case of program code execution on programmable computers, the computing device will generally include a processor, a storage medium readable by the processor (including volatile and non-volatile memory and/or storage elements), at least one input device, and at least one output device. The program(s) can be implemented in assembly or machine language, if desired. The language can be a compiled or interpreted language, and combined with hardware implementations. 
     The methods and apparatuses for implementing and using an XML-based protocol for communications between a CBE and a CBC also can be practiced via communications embodied in the form of program code that is transmitted over some transmission medium, such as over electrical wiring or cabling, through fiber optics, or via any other form of transmission, wherein, when the program code is received and loaded into and executed by a machine, such as an EPROM, a gate array, a programmable logic device (PLD), a client computer, or the like, the machine becomes an apparatus for the utilization of on-demand spam reporting. When implemented on a general-purpose processor, the program code combines with the processor to provide a unique apparatus that operates to invoke the functionality of an XML-based protocol for communications between a CBE and a CBC. Additionally, any storage techniques used in connection with the utilization of an XML-based protocol for communications between a CBE and a CBC can invariably be a combination of hardware and software. 
     While an XML-based protocol for communications between a CBE and a CBC reporting has been described in connection with the various embodiments of the various figures, it is to be understood that other similar embodiments can be used or modifications and additions can be made to the described embodiment for performing the same function of utilizing an XML-based protocol for communications between a CBE and a CBC without deviating therefrom. For example, one skilled in the art will recognize that the utilization of an XML-based protocol for communications between a CBE and a CBC as described in the present application may apply to any environment, whether wired or wireless, and may be applied to any number of such devices connected via a communications network and interacting across the network. Therefore, an XML-based protocol for communications between a CBE and a CBC should not be limited to any single embodiment, but rather should be construed in breadth and scope in accordance with the appended claims.