Abstract:
Various exemplary embodiments relate to a method performed by a policy and charging rules node (PCRN), the method including: receiving a RADIUS accounting request (ACR) start message; applying rules by a rules engine in the PCRN to information in the ACR start message to determine a traffic detection function (TDF) to be updated; determining application detection and control (ADC) rules to be applied to the TDF; and transmitting the determined ADC rules to the determined TDF.

Description:
TECHNICAL FIELD 
       [0001]    Various exemplary embodiments disclosed herein relate generally to communication networks. 
       BACKGROUND 
       [0002]    As the demand increases for varying types of applications within mobile telecommunications networks, service providers must constantly upgrade their systems in order to reliably provide this expanded functionality. What was once a system designed simply for voice communication has grown into an all-purpose network access point, providing access to a myriad of applications including text messaging, multimedia streaming, and general Internet access. In order to support such applications, providers have built new networks on top of their existing voice networks, leading to a less-than-elegant solution. As seen in second and third generation networks, voice services must be carried over dedicated voice channels and directed toward a circuit-switched core, while other service communications are transmitted according to the Internet Protocol (IP) and directed toward a different, packet-switched core. This led to unique problems regarding application provision, metering and charging, and quality of experience (QoE) assurance. 
         [0003]    In an effort to simplify the dual core approach of the second and third generations, the 3rd Generation Partnership Project (3GPP) has recommended a new network scheme it terms “Long Term Evolution” (LTE). In an LTE network, all communications are carried over an IP channel from user equipment (UE) to an all-IP core called the Evolved Packet Core (EPC). The EPC then provides gateway access to other networks while ensuring an acceptable QoE and charging a subscriber for their particular network activity. 
         [0004]    The 3GPP generally describes the components of the EPC and their interactions with each other in a number of technical specifications, including the following components: Policy and Charging Rules Function (PCRF) implemented in a Policy and Charging Rules Node (PCRN); Policy and Charging Enforcement Function (PCEF) implemented in a Policy and Charging Enforcement Node (PCEN); and Bearer Binding and Event Reporting Function (BBERF) of the EPC. These specifications further provide some guidance as to how these elements interact in order to provide reliable data services and charge subscribers for use thereof. 
         [0005]    Today LTE networks interact and interface with traditional wired networks. Such networks may include network access servers (NAS) that connect the wired network to the LTE network. Further, the wired network may include a traffic detection function (TDF). The TDF may analyze network traffic for monitoring, detection, billing, inspection, etc. The TDF may be implemented as a deep packet inspection (DPI) node. Also the TDF may be integrated into other nodes and provide traffic detections functionality along with the other functions of the node. The TDF may send traffic information to the NAS. 
       SUMMARY 
       [0006]    A brief summary of various exemplary embodiments is presented below. Some simplifications and omissions may be made in the following summary, which is intended to highlight and introduce some aspects of the various exemplary embodiments, but not to limit the scope of the invention. Detailed descriptions of a preferred exemplary embodiment adequate to allow those of ordinary skill in the art to make and use the inventive concepts will follow in later sections. 
         [0007]    Various exemplary embodiments relate to a method performed by a policy and charging rules node (PCRN), the method including: receiving a RADIUS accounting request (ACR) start message; applying rules by a rules engine in the PCRN to information in the ACR start message to determine a traffic detection function (TDF) to be updated; determining application detection and control (ADC) rules to be applied to the TDF; and transmitting the determined ADC rules to the determined TDF. 
         [0008]    Various exemplary embodiments relate to a non-transitory computer-readable storage medium encoded with instructions executable by a processor in a and charging rules node (PCRN), the non-transitory computer readable storage medium including: instructions for receiving a RADIUS accounting request (ACR) start message; instructions for applying rules by a rules engine in the PCRN to information in the ACR start message to determine a traffic detection function (TDF) to be updated; instructions for determining application detection and control (ADC) rules to be applied to the TDF; and instructions for transmitting the determined ADC rules to the determined TDF. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    In order to better understand various exemplary embodiments, reference is made to the accompanying drawings, wherein: 
           [0010]      FIG. 1  illustrates an exemplary subscriber network for providing various data services; 
           [0011]      FIG. 2  illustrates the interaction between a PCRN, a plurality of NASs and TDFs; and 
           [0012]      FIG. 3  illustrates the flow of messages in order to implement monitoring rules on a TDF based upon a request by a NAS. 
       
    
    
       [0013]    To facilitate understanding, identical reference numerals have been used to designate elements having substantially the same or similar structure and/or substantially the same or similar function. 
       DETAILED DESCRIPTION 
       [0014]      FIG. 1  illustrates an exemplary subscriber network  100  for providing various data services. Exemplary subscriber network  100  may be a telecommunications network or other network for providing access to various services. Exemplary subscriber network  100  may include user equipment  110 , base station  120 , evolved packet core (EPC)  130 , packet data network  140 , application function (AF)  150 , a network access server  160 , and a traffic detection function node  170 . 
         [0015]    User equipment  110  may be a device that communicates with packet data network  140  for providing the end-user with a data service. Such data service may include, for example, voice communication, text messaging, multimedia streaming, and Internet access. More specifically, in various exemplary embodiments, user equipment  110  is a personal or laptop computer, wireless email device, cell phone, tablet, television set-top box, or any other device capable of communicating with other devices via EPC  130 . 
         [0016]    Base station  120  may be a device that enables communication between user equipment  110  and EPC  130 . For example, base station  120  may be a base transceiver station such as an evolved nodeB (eNodeB) as defined by 3GPP standards. Thus, base station  120  may be a device that communicates with user equipment  110  via a first medium, such as radio waves, and communicates with EPC  130  via a second medium, such as Ethernet cable. Base station  120  may be in direct communication with EPC  130  or may communicate via a number of intermediate nodes (not shown). In various embodiments, multiple base stations (not shown) may be present to provide mobility to user equipment  110 . Note that in various alternative embodiments, user equipment  110  may communicate directly with EPC  130 . In such embodiments, base station  120  may not be present. 
         [0017]    Evolved packet core (EPC)  130  may be a device or network of devices that provides user equipment  110  with gateway access to packet data network  140 . EPC  130  may further charge a subscriber for use of provided data services and ensure that particular quality of experience (QoE) standards are met. Thus, EPC  130  may be implemented, at least in part, according to various 3GPP standards. Accordingly, EPC  130  may include a serving gateway (SGW)  132 , a packet data network gateway (PGW)  134 , a policy and charging rules node (PCRN)  136 , and a subscription profile repository (SPR)  138 . 
         [0018]    Serving gateway (SGW)  132  may be a device that provides gateway access to the EPC  130 . SGW  132  may be the first device within the EPC  130  that receives packets sent by user equipment  110 . SGW  132  may forward such packets toward PGW  134 . SGW  132  may perform a number of functions such as, for example, managing mobility of user equipment  110  between multiple base stations (not shown) and enforcing particular quality of service (QoS) characteristics for each flow being served. In various implementations, such as those implementing the Proxy Mobile IP standard, SGW  132  may include a Bearer Binding and Event Reporting Function (BBERF). In various exemplary embodiments, EPC  130  may include multiple SGWs (not shown) and each SGW may communicate with multiple base stations (not shown). 
         [0019]    Packet data network gateway (PGW)  134  may be a device that provides gateway access to packet data network  140 . PGW  134  may be the final device within the EPC  130  that receives packets sent by user equipment  110  toward packet data network  140  via SGW  132 . PGW  134  may include a policy and charging enforcement function (PCEF) that enforces policy and charging control (PCC) rules for each service data flow (SDF). Therefore, PGW  134  may be a policy and charging enforcement node (PCEN). PGW  134  may include a number of additional features such as, for example, packet filtering, deep packet inspection, and subscriber charging support. PGW  134  may also be responsible for requesting resource allocation for unknown application services. 
         [0020]    Policy and charging rules node (PCRN)  136  may be a device or group of devices that receives requests for application services, generates PCC rules, and provides PCC rules to the PGW  134  and/or other PCENs (not shown). PCRN  136  may be in communication with AF  150  via an Rx interface. As described in further detail below with respect to AF  150 , PCRN  136  may receive an application request in the form of an Authentication and Authorization Request (AAR) from AF  150 . Upon receipt of AAR (not shown), PCRN  136  may generate at least one new PCC rule for fulfilling the application request. 
         [0021]    PCRN  136  may also be in communication with SGW  132  and PGW  134  via a Gxx and a Gx interface, respectively. PCRN  136  may receive an application request in the form of a credit control request (CCR) (not shown) from SGW  132  or PGW  134 . As with AAR, upon receipt of a CCR, PCRN may generate at least one new PCC rule for fulfilling the application request  170 . In various embodiments, AAR and the CCR may represent two independent application requests to be processed separately, while in other embodiments, AAR and the CCR may carry information regarding a single application request and PCRN  136  may create at least one PCC rule based on the combination of AAR and the CCR. In various embodiments, PCRN  136  may be capable of handling both single-message and paired-message application requests. 
         [0022]    Upon creating a new PCC rule or upon request by the PGW  134 , PCRN  136  may provide a PCC rule to PGW  134  via the Gx interface. In various embodiments, such as those implementing the PMIP standard for example, PCRN  136  may also generate QoS rules. Upon creating a new QoS rule or upon request by the SGW  132 , PCRN  136  may provide a QoS rule to SGW  132  via the Gxx interface. 
         [0023]    The PCRN  136  may also communicate with the NAS  160  and the TDF  170 , which will be described in further detail below. 
         [0024]    The PCRN  136  may include network interfaces for communication with other network node, a PCC rule engine, and PCC rule storage. For example, the PCRN  136  may receive an OUT_OF_CREDIT trigger event via the network interface, and pass that event to the PCC rule engine for processing. The PCC rule engine may make decisions regarding existing rules and to create new rules based upon the trigger event. Any new rules or changes to rules may be noted in the PCC rule storage. 
         [0025]    Subscription profile repository (SPR)  138  may be a device that stores information related to subscribers to the subscriber network  100 . Thus, SPR  138  may include a machine-readable storage medium such as read-only memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices, and/or similar storage media. SPR  138  may be a component of PCRN  136  or may constitute an independent node within EPC  130 . Data stored by SPR  138  may include an identifier of each subscriber and indications of subscription information for each subscriber such as bandwidth limits, charging parameters, and subscriber priority. 
         [0026]    Packet data network  140  may be any network for providing data communications between user equipment  110  and other devices connected to packet data network  140 , such as AF  150 . Packet data network  140  may further provide, for example, phone and/or Internet service to various user devices in communication with packet data network  140 . 
         [0027]    Application function (AF)  150  may be a device that provides a known application service to user equipment  110 . Thus, AF  150  may be a server or other device that provides, for example, a video streaming or voice communication service to user equipment  110 . AF  150  may further be in communication with the PCRN  136  of the EPC  130  via an Rx interface. When AF  150  is to begin providing known application service to user equipment  110 , AF  150  may generate an application request message, such as an authentication and authorization request (AAR) according to the Diameter protocol, to notify the PCRN  136  that resources should be allocated for the application service. This application request message may include information such as an identification of the subscriber using the application service, an IP address of the subscriber, an APN for an associated IP-CAN session, and/or an identification of the particular service data flows that must be established in order to provide the requested service. AF  150  may communicate such an application request to the PCRN  136  via the Rx interface. 
         [0028]    The network access server (NAS)  160  provides a single point access to a wireline network. Thus the connection between the NAS and the wireless network allows for direct interaction between the wireless network and the wireline network. Further, the NAS  160  may provide access to a protected network resource. The NAS  160  may connect to the PCRN  136  so that the PCRN  136  may provide policy control for various functions. The NAS  160  may connect to the TDF  170  and receive reports regarding various traffic that the TDF  170  is monitoring. Further, the NAS  160  may connect to the packet data network  140  that might provide, for example, internet access or connectivity to other communication networks. 
         [0029]    The traffic detection function (TDF)  170  analyzes service traffic and applies policies based upon the analysis. The TDF  170  may gate, shape, or redirect the detected traffic based upon the applied policies. The TDF  170  may receive policy information from the PCRN  136  using the Sd DIAMETER application. Further, the TDF  170  may send traffic detection reports to the NAS  160 . Further, the TDF  170  may connect to the packet data network  140  that might provide, for example, internet access or connectivity to other communication networks. 
         [0030]      FIG. 2  illustrates the interaction between a PCRN, a plurality of NASs and TDFs. A PCRN  236 , which may be the same as the PCRN  136  in  FIG. 1 , the plurality of NASs  260   a - c  may be the same as the NAS  160  in  FIG. 1 , and the plurality of TDFs  270   a - b  may be the same as the TDF  270  in  FIG. 1 . Often the TDFs  270   a - b  may be associated with secondary TDFs (not shown) that provide a back up functionality if a TDF fails. Further, the NAS may use RADIUS messages to provide control and management to other network elements. Accordingly, the PCRF may include the ability to receive and process RADIUS messages. Also, the PCRF may use DIAMETER messages to communicate with the TDFs  260 . Therefore, the PCRN  236  may receive information from RADIUS messages received from the NASs  270  and map such information as needed into DIAMETER messages sent to the TDFs  260 . 
         [0031]    The monitoring of the traffic by the TDF  260  may be specified using application detection and control (ADC) rules. ADC rules apply the detection and enforcement actions for the specified application traffic. In systems including both wireless and wireline elements, the powerful rule engine of the PCRN  236  may be used to assign ADC rules to TDFs  260  based upon requests received from NASs  270 . The NAS may use an accounting request (ACR) start message to request that traffic be monitored. Previously a PCRN  236  may have used a very large look up table to determine based upon various ACR-Start parameters which TDF to provision with ADC rules to monitor the desired traffic. Such a process is very cumbersome to manage, maintain, and keep accurate. Accordingly, the rule engine in the PCRN  236  may instead be used to apply rules to determine which TDF to select to monitor the traffic and what specific ADC rules to provision to the selected TDF. 
         [0032]      FIG. 3  illustrates the flow of messages in order to implement monitoring rules on a TDF based upon a request by a NAS. The NAS  270  may send and ACR-Start message to the PCRF  236  including information. The information in the ACR-Start message may be in the form of attribute-value pairs (AVP). The PCRF may initiate a NASSession based upon the ACR-Start message. Next, the PCRF may apply rules to information received in the ACR-Start message (e.g., IP address, port id, region code, user or customer specified data, etc.) as well as based upon NASSession information (e.g., IP address, subscriber information, etc.) to determine which ADC rules need to be applied and to which TDFs  260  the ADC rules apply. Then the PCRN  236  may send a CCR-I (initial CCR) message specifying ADC rule 1 to TDF(1)-Primary 260. TDF(1)-Primary installs ADC rule 1 to monitor traffic and sends back a CCA-I (initial credit and control) message to the PCRF  236  to acknowledge receipt of the CCR-I message. Going forward TDF(1) primary may send reports to either the PCRF  236  or the NAS  270  regarding the monitored traffic. Further, if TDF(1)-Primary has a secondary TDF, TDF(1)-Secondary, the PCRF may also send a CCR-I specifying ADC rule 1 to TDF(1)-Secondary. TDF(1)-Secondary may respond with a CCA-I message. Once the PCRF  236  has received acknowledgements that the TDFs have receive the specified ADC rule(s), the PCRF  236  may send an ACR-Start-ACK (ACR-Start acknowledge) message back to NAS. 
         [0033]    The NAS may send an ACR-Stop message to stop monitoring of specific traffic. The PCRF  236  may apply rules to the ACR-Stop message to determine the specific ADC rules to terminate and which TDFs have ADC rules installed. The PCRF  236  may then send termination messages to the determined TDFs to terminate the specified ADC rules. 
         [0034]    The rules that the PCRF  236  may apply may be based upon any parameter or parameters related to the NAS, the user, etc. In  FIG. 3  rules based upon the port number are provided as an example. If the port number is greater than 0 and less than or equal to  1000 , then ADC rule 1 is to be installed in TDF(1)-Primary and TDF(1)-Secondary. If the port number is greater than 1000 and less than or equal to 2000, then ADC rule 1 is to be installed in TDF(2)-Primary and TDF(2)-Secondary. If the port number is greater than 2000 and less than or equal to 3000, then ADC rule 2 is to be installed in TDF(n)-Primary and TDF(n)-Secondary. The rules may be based upon customer requirements, network requirement, or other requirements as needed. The rules may be as complex, using various parameters, logic, and hierarchies, or as simple as needed. The use of the rule engine in the PCRF  236  provides the ability to manage the provisioning of ADC rules in TDFs in a much more flexible manner without the need to create and maintain a large look up table. The use of the PCRN rule engine provides the advantage of being able to quickly modify the application of ADC rules for groups of network elements and for situations where similar ADC rules would be applied. Also different parameter types may be used to determine different ADC rules to be applied as well as the TDFs to be used. This is especially beneficial when the managed network may include 100s of NASs and TDFs. 
         [0035]    It should be apparent from the foregoing description that various exemplary embodiments of the invention may be implemented in hardware and/or software instructions enacted on a processor. Furthermore, various exemplary embodiments may be implemented as instructions stored on a machine-readable storage medium, which may be read and executed by at least one processor to perform the operations described in detail herein. A machine-readable storage medium may include any mechanism for storing information in a form readable by a machine, such as a personal or laptop computer, a server, or other computing device. Thus, a tangible and non-transitory machine-readable storage medium may include read-only memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices, and similar storage media. 
         [0036]    It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative circuitry embodying the principles of the invention. Similarly, it will be appreciated that any flow charts, flow diagrams, state transition diagrams, pseudo code, and the like represent various processes which may be substantially represented in machine readable media and so executed by a computer or processor, whether or not such computer or processor is explicitly shown. 
         [0037]    Although the various exemplary embodiments have been described in detail with particular reference to certain exemplary aspects thereof, it should be understood that the invention is capable of other embodiments and its details are capable of modifications in various obvious respects. As is readily apparent to those skilled in the art, variations and modifications can be effected while remaining within the spirit and scope of the invention. Accordingly, the foregoing disclosure, description, and figures are for illustrative purposes only and do not in any way limit the invention, which is defined only by the claims.