Cisco ASR 5000 Series, Обзор продукта

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Serving GPRS Support Node (SGSN) Overview
▀ Features and Functionality - Basic
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
For commands and information on network sharing configuration, refer to the Service Configuration Procedures section
in the
SGSN Administration Guide and the command details in the Command Line Interface Reference .
Session Management
Session management ensures proper PDP context setup and handling.
For session management, the SGSN supports four 3GPP-compliant procedures for processing PDP contexts:
Activation
Modification
Deactivation
Preservation
PDP Context Activation
The PDP context activation procedure establishes a PDP context with the required QoS from the MN to the GGSN.
These can be either primary or secondary contexts. The SGSN supports a minimum of 1 PDP primary context per
attached subscriber, and up to a maximum of 11 PDP contexts per attached subscriber.
The PDP context types supported are:
PDP type IPv4
PDP type IPv6
PDP type PPP
Both dynamic and static addresses for the PDP contexts are supported.
The SGSN provides configuration to control the duration of active and inactive PDP contexts.
When activating a PDP context the SGSN can establish the GTP-U data plane from the RNC through the SGSN to the
GGSN or directly between the RNC and the GGSN (one tunnel).
The SGSN is capable of interrogating the DNS infrastructure to resolve the specified APN to the appropriate GGSN.
The SGSN also provides default and override configuration of QoS and APN.
PDP Context Modification
This procedure is used to update the MN and the GGSN. The SGSN is capable of initiating the context modification or
negotiating a PDP context modification initiated by either the MN or the GGSN.
PDP Context Deactivation
This procedure is used to deactivate PDP contexts. The procedure can be initiated by the MN or the SGSN. The SGSN
provides configurable timers to initiate PDP deactivation of idle contexts as well as active contexts.