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Services Control Gateway and TDF Overview


The Services Control Gateway application resides on an MX Series router and implements the traffic detection functionality (TDF) defined by the Third-Generation Partnership Project (3GPP). A TDF performs application detection on user traffic to determine the services and charging for an individual subscriber’s traffic. A TDF determines the application being used by performing deep packet inspection (DPI) of the traffic, reports the use of the application to the Policy and Charging Control Rules Function (PCRF) over the Gx interface, receives policy rules from the PCRF, and enforces the policy rules on the subscriber’s traffic. A TDF is integrated with the PCRF and the Online Charging System (OCS).

The Services Control Gateway is a subscriber-aware and application-aware service delivery network edge element, located between the gateway of the access network and the public network and network services. This is shown in . The Services Control Gateway provides services as rich as if they were provided directly on the access network gateway.

The Services Control Gateway handles traffic from multiple types of access network gateways, allowing access-independent subscriber-aware services in a converged manner for wireline and mobile access. The subscribers may be controlled by a broadband network gateway (BNG) in a wireline access network, by a gateway GPS support node (GGSN) in a 2G or 3G network architecture, and by a packet data network gateway (PGW) in a 4G/LTE network architecture.

If the Services Control Gateway is used without a PCRF, you must configure static policies.

This release of the Services Control Gateway does not support charging.

The Services Control Gateway provides the following features and benefits:

  • Provides services such as application identification through DPI, HTTP header enrichment, and network address translation (NAT).

  • Provides support for application-based polices with pre-11 release PCRFs by using enhanced Policy and Charging Control (PCC) rules that are supported on the Gx interface.

  • Steers application-level flows toward external chained services or internal chained services.

  • Delivers fixed-mobile convergence (FMC) services.

  • Alerts the PCRF when a subscriber has started using an application.

  • Enables service providers to create personalized services in an easy, quick, and cost-effective manner.

  • Optimizes the cost structure of Gi LAN/value-added services (VAS) through optimal service orchestration.