Abstract:
A switching system receives a first message for a call and transfers a second message. A centralized processing system processes the second message to identify first route information and redirect capability for the first called party, and transfers a third message indicating the first route information and redirect capability. The switching system processes the third message to initiate first communications between the caller and first called party. The switching system receives and processes a fourth message from the first called party indicating redirect information for a second called party to transfer a fifth message indicating the redirect capability and the redirect information. The processing system receives and processes the fifth message to identify second route information, and transfers a sixth message indicating the second route information. The switching system processes the sixth message to initiate second communications with the second called party.

Description:
RELATED APPLICATIONS  
       [0001]     This application is a continuation of pending application Ser. No. 09/345,936, filed Jul. 1, 1999, entitled “TELECOMMUNICATIONS SYSTEM WITH CENTRALIZED CALL REDIRECTION CONTROL LOGIC AND SPEED DIAL TRANSLATION LOGIC,” which is hereby incorporated by reference into this application. 
     
    
     FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     Not applicable  
       MICROFICHE APPENDIX  
       [0003]     Not applicable  
       BACKGROUND OF THE INVENTION  
       [0004]     1. Field of the Invention  
         [0005]     The invention relates to a telecommunications system, and specifically, to a centralized processing system having call redirection and translation processing logic.  
         [0006]     2. Description of the Prior Art  
         [0007]     In a telecommunications network, an SCP provides service information to devices in the network using call processing applications within the SCP. Some examples of service information provided by the SCP include special service number routing information and calling card information. For instance, a switch receives a call requiring a special service to complete the call to a called destination. Recognizing the need for a service, the switch transmits a query message to the SCP. The SCP processes the query message and returns a response message containing service information for the call. These query and response messages are generally Signaling System #7 (SS7) Transaction Capabilities Application Part (TCAP) protocol messages that are well known in the art.  
         [0008]     Unfortunately, SCP architectures and operation do not effectively support call redirection services or speed dial translation processing, which is commonly used to initiate call redirection. Presently, call redirection control logic is included in communication devices that also include the call connection capabilities to redirect the call. In addition, speed dial translation processing is also located in the communication devices having call redirection control logic and connection capabilities. One example of such a communication device is a telecommunications switch.  
         [0009]     In an example of call redirection, a call is received in a switch having call redirection control logic and call connection capabilities. The call is then connected between the caller and a first called party. Where the first called party has subscribed to a call redirection service, the call can be redirected by a caller-entered command, such as a speed dial number. The switch processes the speed dial using internal redirection and translation processing logic and extends the call to a second called party.  
       SUMMARY OF THE INVENTION  
       [0010]     Examples of the invention include a communication system and its method of operation. The communication system comprises a switching system and a centralized processing system. The switching system is configured to receive a first message indicating a called number for a call from a caller to a first called party and to process the called number to transfer a second message indicating the called number. The centralized processing system is configured to receive the second message and process the called number to identify first route information and redirect capability for the first called party, and to transfer a third message indicating the first route information and the redirect capability. The switching system is further configured to receive the third message and process the first route information to initiate first communications between the caller and the first called party, and to receive a fourth message from the first called party indicating redirect information for redirecting the call to a second called party and process the redirect information to transfer a fifth message indicating the redirect capability and the redirect information. The centralized processing system is further configured to receive the fifth message and process the redirect capability and the redirect information to identify second route information, and to transfer a sixth message indicating the second route information. The switching system is further configured to receive the sixth message and process the second route information to initiate second communications with the second called party.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]      FIG. 1  illustrates a system architecture in an example of the present invention;  
         [0012]      FIG. 2  illustrates a message sequence diagram for a call redirection in an example of the invention;  
         [0013]      FIG. 3  illustrates an SCP architecture in an example of the present invention;  
         [0014]      FIG. 4  illustrates a call processing architecture in an example of the present invention;  
         [0015]      FIG. 5  illustrates a network architecture in an example of the present invention;  
         [0016]      FIG. 6  illustrates a flow diagram of translation data structure processing in an example of the present invention; and  
         [0017]      FIG. 7  illustrates a flow diagram of class of service screening and class of service override in an example of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0018]      FIG. 1  depicts SCP  100  and switching system  102 . SCP  100  comprises processing system  103  and interface  101 . Processing system  103  comprises translation call processing application  105 . One skilled in the art will appreciate that processing system  103  would include other call processing applications although only translation call processing application  105  is shown for clarity. Switching system  102  is connected to interface  101  by link  104 . One example of switching system  102  could be one or more telecommunications switches commonly known and used in the art. Link  104  could be any link capable of exchanging messages between interface  101  and switching system  102 . Interface  101  is connected to processing system  103  by link  106 . Link  106  could be any link capable of exchanging messages between interface  101  and processing system  103 .  
         [0019]     Processing system  103  could be any processing system capable of: 1) processing a first message to generate a second message containing first call handling information for a call, and 2) process a third message containing a speed dial number to generate a fourth message with second call handling information for the call. Processing system  103  uses translation call processing application  105  for translation and processing of the speed dial number.  
         [0020]     In the context of this application a speed dial number is defined as five or less touch tone characters. The touch tone characters could be five or less digits or a combination of digits and other characters including without limitation, the asterisk character and/or the octothorpe character. It should be noted that in the context of this application, the first, second, third, fourth, etc. connotations used to reference the messages are used solely for the purpose of differentiating between different messages and are not used to indicate a message sequence or processing sequence.  
         [0021]     Interface  101  could be any interface capable of: 1) receiving the first message from switching system  102 , 2) transmitting the second message with the first call handling instructions for switching system  102 , 3) receiving the third message with the speed dial instruction from switching system  102 , and 4) transmitting the fourth message with the second call handling information for switching system  102 .  
         [0022]      FIG. 2  depicts a message sequence chart for a call redirection using an SCP  202  in an example of the present invention, but those skilled in the art will recognize numerous other configurations that are applicable to the invention described above. Those skilled in the art will also appreciate how combinations of features described below can be combined with the above-described embodiment.  
         [0023]     In  FIG. 2  the caller  200  places a call to a first called party  203 . The call is received by a switching system  201 , which generates a first message for SCP  202  to obtain call handling information. SCP  202  processes the first message to generate a second message containing first call handling information for the call and transmits the second message for switching system  201 . Switching system  201  uses the first call handling information to extend the call to a first called party  203 . First called party  203  then enters a speed dial number that instructs switching system  201  to redirect the call to a second called party  204 . Switching system  201  generates a third message for SCP  202  that includes the speed dial number to obtain call handling information for the call. SCP  202  processes the third message with the speed dial number to generate a fourth message with second call handling information for the call and transmits the fourth message to switching system  201 . The second call handling information causes switching system  201  to extend the call to a second called party  204 .  
         [0024]     Upon extending the call to the second called party  204 , several options for call connection are available. One option is to connect caller  200 , first called party  203  and second called party  204  in a conferenced conversation. Another option is to place caller  200  on hold while first called party  203  and second called party  204  converse in conversation. Yet another option, is to disconnect first called party  203  wherein caller  200  and second called party  204  converse in conversation.  
         [0000]     SCP Architecture and Operation:  
         [0025]      FIG. 3  depicts an SCP architecture and a switch in an example of the present invention, but those skilled in the art will recognize numerous other configurations that are applicable to the invention described above. Those skilled in the art will also appreciate how combinations of features described below can be combined with the above-described embodiment.  
         [0026]      FIG. 3  depicts SCP  300  and switch  301 . SCP  300  comprises processing system  309 , links  303  and  308 , and interface  302 . Processing system  309  comprises central processing units (CPUs)  304 ,  305  and  306  and database  307 . As those skilled in the art are aware, a processing system can be comprised of a single CPU or can be distributed across multiple CPUs. Multiple CPUs are depicted in  FIG. 3  although only CPUs  304 ,  305 , and  306  are shown for clarity. Switch  301  could be a communication switch capable of conforming to the interface message rules for interacting with SCP  300 . One example of switch  301  is a DMS-250 available from Nortel, and modified in accordance with the present invention.  
         [0027]     Interface  302  is connected to CPUs  304 ,  305  and  306  by link  303 . Database  307  is connected to CPUs  304 ,  305  and  306  by link  308 . Switch  301  is connected to interface  302  by link  310 . Link  310  could be any link capable of exchanging messages between interface  302  and switch  301 . One example of link  310  could be a link having SS7 message transfer part functionality and SS7 signaling connection control part functionality that is known in the art. Although they are not shown for clarity, interface  302  could handle numerous such links to other elements in a telecommunications network.  
         [0028]     Processing system  103  could be any processing system where one of CPUs  304 ,  305  or  306  is capable of: 1) processing a first message that includes a speed dial number to generate a second message containing call handling information for a call. Although the call handling information can include other instructions, it is typically routing information to one or more switches in the network and connection to a call destination. CPUs  304 ,  305  and  306  access database  307  to support call processing. An example of processing system  309  including CPUs  304 ,  305  and  306 , link  308 , and database  307  is the Tandem Himalaya loaded with the Tandem Guardian operating system, in addition to database management software and various conventional utilities. Link  303  could be any link for interfacing processors and exchanging messages between interface  302  and processors  304 ,  305  and  306 . Link  308  could be any link for interfacing processors and exchanging messages between database  307  and processors  304 ,  305  and  306 .  
         [0029]     Interface  302  could be any interface capable of receiving a first message with a speed dial number and transmitting a second message with call handling information for switch  301 . An example of interface  302  could be an interface configured to receive multiple messages in multiple protocols and provide access to processing system  309 .  
         [0030]      FIG. 4  illustrates the operation of the processing logic in CPU  304  of SCP  300  in some embodiments of the invention. The processing logic in other CPUs would be similar. Those skilled in the art will appreciate that numerous other configurations of the processing logic can be derived from the following example that are within the scope of the invention. Those skilled in the art will also appreciate how the principles illustrated in this example can be used in other examples of the invention.  
         [0031]      FIG. 4  depicts CPU  304 , which includes message interface  402 , service discrimination process  403 , translation data structure  404 , destination data structure  406 , optional decision data structure  409 , treatment data structure  407 , digit collection data structure  405  and default data structure  408 .  
         [0032]     CPU  304  uses message interface  402  to exchange messages with interface  302 . CPU  304  processes the messages from message interface  402  using data structures. A data structure is a logical table that can be entered using information or pointers to yield additional information or a pointer to another data structure. Those skilled in the art will appreciate that CPU  304  could include other data structures but only data structures  404 ,  405 ,  406 ,  407 ,  408 , and  409  are shown for clarity. CPU  304  processes the data structure until the data structure yields either the desired information or a pointer to another data structure.  
         [0033]     For example, CPU  304  could enter the translation data structure  404 . Translation data structure  404  is used during call processing for digit manipulation, including without limitation, the translation of speed dial numbers and other digit strings passed in messages to CPU  304 . The translation data structure  404  matches digits in a message against digits defined in translation data structure  404  and selects a next tree data structure based on the message digits. The message digits could be a speed dial number or digits collected by digit collection data structure  405 . The defined digits could be a called party&#39;s number, a tree ID pointing to digit collection data structure  405  or a trigger index for the service discrimination process  403 .  
         [0034]     The digit collection data structure  405  is used to collect digits from a caller and to match or validate the collected digits against defined digits within digit collection data structure  405 . The digit collection data structure  405  can yield a pointer to one of the other data structures for additional call processing or generate a query message for message interface  402  with digit collection instructions. The digit collection data structure  405  can yield a pointer to the destination data structure  406 , the treatment data structure  407 , the default data structure  408 , the optional decision data structure  409  or the translation data structure  404 .  
         [0035]     Digit collection data structure  405  could point to destination data structure  406  for the generation of call handling information. Destination data structure  406  yields a selected switch and connection for the call, and produces an SCP response message with this call handling information for the message interface  402 . Digit collection data structure  405  could also point to treatment data structure  407  for the generation of call handling information. Treatment data structure  407  is used to reject calls or apply any treatment for the given call profile. Treatment data structure  407  produces an SCP response message for message interface  402 . Digit collection data structure  405  could also point to default data structure  408  for the generation of call handling information. Default data structure  408  is used to provide default connections or handle mistakes in the data structures. Default data structure  408  produces an SCP response message for the message interface  402 .  
         [0036]     Optional decision data structure  409  is used to apply additional logic to the call as would be appreciated by those skilled in the art. Some examples of such additional logic are data structures for processing the call based on a time of day, II digits, call distribution, or remote processor information. Optional decision data structure  409  points to destination data structure  406 , treatment data structure  407  or default data structure  408 .  
         [0000]     Call Redirection:  
         [0037]      FIG. 5  illustrates a network architecture in an example of the present invention, but those skilled in the art will recognize numerous other configurations that are applicable to the invention described above. Those skilled in the art will also appreciate how combinations of features described below can be combined with the above-described embodiment.  
         [0038]     Call redirection is a feature, which allows an incoming call to be redirected or transferred by the called party to another number. The original call is typically an inbound toll-free call to a dedicated location. The redirect can be a speed dial number, a toll-free number, a Virtual Private Network (VPN) toll-free number or a Plain Old Telephone Service (POTS) number including international numbers.  
         [0039]     The redirect is completed by either: 1) transferring the call to another location without ensuring the outcome, an unconfirmed redirection; 2) transferring the call to another location with confirmation of results, a confirmed redirection; or 3) transferring the call to another location with the option of a three-way conference, a consultative redirection.  
         [0000]     Example of Call Redirection:  
         [0040]     In one example of the present SCP with call redirect, a caller accesses the switch by dialing a toll-free number to a first called party. Once the caller to first called party initial leg call is established and the first called party has answered the call, the terminating primary rate interface (PRI) trunk is monitored for possible call redirection activation. The first called party controls the call redirection by entering a speed dial number (“feature code”). The first called party enters the redirection activation feature code and then the address digits for a second called party. Examples of address digits for the second called party could include without limitation, 6 or 7 digit On-Net, Off-Net or International direct distance calling, a second toll-free number, or a 1, 2, 3, 4, or 5 digit speed dial number.  
         [0041]     The consult leg call (call from first called party to a second called party) is extended to the second called party. If the first called party drops from the call, the second called party may, if eligible, redirect the call to another called party. At any point where a party receiving a call may has call redirection capability, it is possible for that party to conduct any number of consult leg calls, one after another.  
         [0042]     In another example of the present SCP with call redirect, a caller places a call to a first called party by dialing a special service number. The originating switch launches a query message to the SCP. The SCP returns routing information along with an indicator that defines the first called party&#39;s redirection capability. The call is routed through the terminating switch to the called party. The switch sends the appropriate first called party address and Automatic Number Identification (ANI) information to the first called party&#39;s PBX. The first called party answers the phone and converses with the caller. The first called party dials the redirect activation feature code. The terminating switch recognizes the feature code and allocates a conference bridge for the call and places the caller on hold. The terminating switch sends a query message to the SCP with the feature code command. The SCP responds in conversation mode directing the switch to collect and return the address digits. The switch connects a receiver to the called party to collect the digits and passes them to the SCP. The SCP processes the collected digits and responds with routing information for the call redirect. The switch extends the call to the second called party and first called party and second called party converse while the caller is on hold.  
         [0043]     The first called party then dials the feature code for a conference call and the controlling switch&#39;s conference bridge connects the caller, first called party and second called party together. The first called party hangs up and is released from the call and the caller and the second called party converse.  
         [0000]     SCP Functionality:  
         [0044]     When a caller dials a toll-free number, the SCP returns information related to the called party&#39;s redirect capabilities in addition to returning the called party&#39;s routing information to the switch. When the switch receives the redirect activation feature code it will have been data-filled to query the SCP with the filed authorization code. The SCP selects a routing tree based on the authorization code and the redirect event. The routing tree causes the collection of digits and returns a route choice for redirection or a treatment to the switch. Because the SCP is controlling digit collection for the redirect leg, the switch cannot provide class of service screening and class of service override. Class of service screening and class of service override are provided by the SCP based on criteria including without limitation, Network Performance and/or time of day. Alternatively, the SCP may collect an override code allowing the completion of a restricted call. On the other hand the SCP may also return to the switch along with a route choice, the information that a class of service screening was encountered but override functionality wasn&#39;t performed. This enables the switch to provide for the override.  
         [0045]     The SCP is enhanced to provide private speed dial lists and class of service screening and class of service override. The SCP is also enhanced with a redirection field and the redirection type field in the caller information parameter. If the redirection field indicates that redirection is allowed then the redirection type field should contain a valid index into the Redirect Request Information (RDRINFO) table of the switch. This index indicates the type of redirection to perform for the call; either unconfirmed, confirmed, or consultative. If the redirection field is set to disallowed the redirection type field is not used and no call redirection is allowed for the call. If the redirection field is set to in-switch the redirection type field is not used and call redirection is performed based on in-switch logic. These fields have the capability to be defined based on both the dialed number and the destination trunk group.  
         [0046]     In addition to having the ability to redirect a caller to a toll-free number, private number, or POTS number, the called party has the ability to enter a speed dial code including 1, 2, 3, 4, or 5 digits followed optionally by an octothorpe (#), instructing the network to dial a pre-defined number. The speed dial number will typically be preceded by the asterisk (*) character. The octothorpe forces a dial timer to expire, resulting in expedited speed dial calls. The customer has one speed dial list for an entire trunk group.  
         [0047]     There are two types of speed dial lists. The first list treats any number given that is not in its list. The second passes all numbers, even those not in its list, on for further processing. These choices are necessary for customers to restrict redirection to a speed dial list.  
         [0048]     All call redirect enabled trunk groups are data-filled to trigger QueryImmed on the Originate Point In Call (PIC) with a PIC Qualifier of Redirection. Service Discrimination is modified to handle a query with this PIC/PIC Qualifier and the new trigger index. The authorization code passed with this query is used to access a tree whose first data structure is a digit collection data structure configured to collect address digits.  
         [0049]     A dedicated trunk group may have several toll-free numbers terminating on it. Some of these toll-free numbers allow redirection and some of them do not. Of those that allow redirection some allow unconfirmed, and some allow another redirection type. Each toll-free number terminating on the trunk group may define its redirect capabilities independent of all other toll-free numbers.  
         [0050]     Additionally, toll-free numbers may utilize call processing data structures to terminate to one of several destinations or dedicated trunk groups. Some of these destinations allow redirection and some do not. Of those that allow redirection, some allow unconfirmed redirection and some allow another redirection type. Each destination or dedicated trunk group for a toll-free number may define its redirection capabilities irrespective of all other destinations for that toll-free number. The values for redirection and redirection index that are returned to the switch in the call information parameter are stored in the Terminating Feature Table. It should be noted that the addition of these fields to the Terminating Feature Table requires a conversion of existing Terminating Feature Tables in the SCP.  
         [0051]     If a destination data structure does not include a Terminating Feature Table or if its Terminating Feature Table does not contain values for redirection and redirection index, then call processing uses the default values for both fields when filling in the call information parameter. Call processing recognizes whether values are required for redirection and redirection index based on the size of the call information parameter passed in the TCAP query. An eight octet call information parameter indicates that redirection and redirection index values are required. A seven octet call information parameter requires no values for redirection or redirection index.  
         [0000]     Treatment Data Structure:  
         [0052]     A new message type, “Feature Action,” is introduced to the SCP treatment data structure. The SCP uses the existing TCAP response when the treatment data structure encounters a message type condition of feature action and a “treatment value” exists. The response contains a feature action parameter that contains the “treatment value” assigned to the error code. The treatment data structure and error number are treated as a legal next tree and next data structure identifier respectively, for entries in the digit collection data structure and a dialed number data structure.  
         [0000]     Digit Collection Data Structure:  
         [0053]     The digit collection data structure is the initial data structure encountered in the SCP on a redirect leg query. This data structure is configured in one of two modes. The first mode defines a set of valid number ranges and a default that points to treatment for any numbers not in the ranges provided. This satisfies the restrictive speed dial list requirement. The second mode passes on all numbers received. This is accomplished by the correct definition of number ranges or by defining a default tree ID and next data structure.  
         [0054]     The switch receives a call redirect activation feature code from the first called party. The switch connects a receiver to the first called party and launches an SCP query. Through the service discrimination process a routing tree is selected that contains the digit collection data structure as its first data structure. The digit collection data structure causes the SCP to enter conversation mode and requests 1 to 16 address digits from the switch. The switch returns the digits. The digit collection data structure uses these digits to derive a next tree ID and next data structure to generate call routing information for the redirection request. The end result is a TCAP response containing call routing information that the switch uses to terminate the call to the second called party. The collected digits could be a speed dial number, a POTS number, a VPN number, or toll-free number. In addition, the speed dial numbers will translate to either a POTS, VPN or toll-free number. Alternatively the address returned to the SCP could be a feature code that deletes a partially entered redirection number to release the consult leg and revert to a two party call or a feature code that returns to the caller. In either case the SCP returns a feature action parameter as part of the TCAP response to instruct the switch to revert to a two-party call.  
         [0000]     Translation Data Structure:  
         [0055]     Triggering on the originate PIC and collecting address digits in TCAP conversation mode bypasses translation that is currently done in the switch. Since conversation mode is being used to collect the address digits on the redirect leg, translation is now performed in the SCP requiring the definition of a translation data structure.  
         [0056]     Translation provides three key functions. The first of these functions is digit manipulation. This functionality allows the translation of speed dial numbers and may also be used to strip the leading 1 from digits provided through the digit collection data structure process. The second function matches digits against the digits associated to the translation data structure and selects a next tree/initial data structure. This function occurs after any digit manipulation. The third function is the most critical. The third function associates a trigger index with a range of digits defined in the translation data structure. This function then re-invokes service discrimination using the new trigger index as well as any number translation that has been done. Through human error, it may be possible that a number range is defined in the digit collection data structure and points to the translation data structure, but that number range is not present in the translation data structure. When this condition occurs, the SCP uses the treatment data structure to complete the call.  FIG. 6  illustrates a flow diagram of the translation data structure processing in an example of the present invention.  
         [0057]     A translation data structure is added to the SCP architecture. The translation data structure provides the data for several functions. Amongst these is translation of speed dial numbers and assignment of trigger indexes. Once translation is done, service discrimination is invoked again taking advantage of the information from the digit collection data structure and the translation data structure. At a minimum each entry in the translation data structure will contain the following information:  
                                           From Digits   Up to 16 Digits   The beginning range of the       Range       collected number       To Digits   Up to 16 Digits   The ending range of the       Range       collected number       Delete Digits   Blank, or 0-16   The number of digits to               delete from the collected               number. These digits are               deleted from the beginning               of the dialed number       Prefix Digits   Blank, or 0-   Digits to be prefixed to the           9999999999999999   collected number. The digits               would be prefixed after any               digit deletion occurred.       Trigger Index       Trigger Index used to re-               invoke Service               Discrimination.       Class of service   Y/N   Y if class of service       Encountered       screening is defined for this               range, N otherwise       Call Type       What is the type of this call               (e.g. International, Direct               distance dial, On-net)       Check class of   Y/N   Y if the switch needs to       service override       perform the Class of Service               Override Check       Next Data       Structure                  
 
 Class of Service Screening and Class of Service Override: 
 
         [0058]     Because digit collection on the redirect leg is done in conversation mode and because speed dial translation is done at the SCP, class of service screening and class of service override previously done only at the switch are now done in the SCP. Class of service screening at the switch blocks or allows calls based on several criteria. For example, screening could be based on call type (International, Direct Dial, or On-net), on call type and time of day, or on call type and destination number. Finally screening could be based on call type, time of day and destination number. If class of service override (COSOVE) is allowed then a subscriber exceeding a defined Class or Service (COS) can override the treatment by entering an override authorization code. One skilled in the art will appreciate that COSOVE could be provided both in the SCP and in the switch. If COSOVE is done in the switch, the SCP returns with the routing information a request for the switch to perform the COSOVE. If the switch is requested to perform the COSOVE, a call type is returned with the routing information. If COSOVE is checked at the SCP and fails, the COS treatment is returned to the switch. If COSOVE is checked at the SCP and succeeds the remainder of the routing tree is processed.  
         [0059]     As illustrated by  FIG. 7 , class of service screening and class of service override are provided through the digit range mechanism defined for the translation data structure and the use of other existing data structures including but not limited to, the time of day and the dialed number data structures. In addition, since the SCP doesn&#39;t use call type information, defining number ranges in the translation data structure provides the equivalent of screening on call type.  
         [0060]     If class of service override is handled in the SCP then another digit collection data structure is the next data structure encountered. Otherwise the switch is told the call type and the following facts: 1) that COS was encountered, 2) that COSOVE wasn&#39;t performed, and 3) that COSOVE should be checked. This is the reason for two (2) fields in the translation data structure and one (1) field in the terminating feature table.  
         [0000]     TCAP Requirements:  
         [0061]     When the SCP is utilized for routing a call, the SCP controls the redirecting capabilities for that call and defines the call redirection rules. The call redirection rules include but are not limited to instructing the switch to allow redirection capabilities for a call, disallow redirection capabilities for a call, or indicate that the switch must use in-switch logic for determining whether call redirection is allowed for the call. This enables the SCP to send an index into table RDRINFO by modifying the TCAP call information parameter. The following rules apply to SCP operation: 
    1) If the SCP indicates that redirection is to be allowed via the existing redirection field in the call information parameter, then the new redirection index into table RDRINFO provided by the SCP indicates the redirection type to perform for the call.     2) If the SCP indicates that redirection is to be disallowed via the existing redirection field in the call information parameter, then the new redirection index provided by the SCP is not used, and no call redirection is allowed for the call.     3) If the SCP indicates that redirection is to be based on in-switch logic via the existing redirection field in the call information parameter, then the new redirection index provided by the SCP is not used, and call redirection performed by the call is based on in-switch logic.    
 
         [0065]     When the SCP is queried on the redirect leg it goes into conversation mode to collect the address digits. The address digits could be a feature code that deletes a partially entered redirection number to release the consult leg and revert to a two party call or a feature code that returns to the caller. When the SCP sees either of these it instructs the switch to revert to a two party call by returning the feature action parameter. Since the address digits are collected in conversation mode during the redirect leg, it is necessary to implement class of service screening at the SCP. This implementation allows the SCP to request that the switch perform the COSOVE function. The SCP fills a specific field in the destination parameter and includes the miscellaneous parameter in the TCAP response to request the switch perform COSOVE. This enables the SCP to indicate the type of redirection to perform by adding an octet for use in the TCAP call information parameter for TCAP response and query messages. This octet is used to encode the 10 bit redirection index returned from the SCP. In addition an existing octet has 2 bits that indicate whether redirection is allowed or not.  
         [0066]     Redirection is a 2-bit field with its least significant bit in bit  6  of octet  4  and its most significant bit in bit  7  of octet  4 . The redirection index is 10 bits in length and is encoded beginning with the most significant bit in bit  7  of octet  8  and the least significant bit in bit  6  of octet  7 . The SCP directs the switch to revert to a two party call by returning the feature action parameter in the TCAP response message. COS encountered is returned to the switch in an optional miscellaneous parameter as part of the TCAP response. This parameter also contains a COSOVE performed field, which should be set to no if the switch is to perform COSOVE.  
         [0000]     SCP Call Detail Records (CDR) Requirements:  
         [0067]     Address digits are collected in conversation mode through the use of the digit collection data structure and are fed through a translation process. Likewise, COSOVE may require the collection of a COSOVE code in conversation mode through the use of a digit collection data structure. These digits are written to the SCP CDR using the digits collected field. A digit type already exists for COSOVE and for destination digits. A new digit type with a value of 8 is added to identify speed dial digits in the digit collected field.  
         [0068]     The SCP CDR captures the data structures traversed during the processing of a call. The data structures traversed field of the CDR contains the predefined data structure values assigned to each decision and destination data structure. The translation data structure includes a predefined data structure value of 18 that is recorded to the SCP CDR field “data structures traversed” each time the data structure is encountered for a call.  
         [0069]     The above-described elements can be comprised of instructions that are stored on storage media. The instructions can be retrieved and executed by a processor. Some examples of instructions are software, program code, and firmware. Some examples of storage media are memory devices, tape, disks, integrated circuits, and servers. The instructions are operational when executed by the processor to direct the processor to operate in accord with the invention. The term “processor” refers to a single processing device or a group of inter-operational processing devices. Some examples of processors are integrated circuits and logic circuitry. Those skilled in the art are familiar with instructions, processors, and storage media.