Cisco Cisco Packet Data Gateway (PDG) Manuale Di Manutenzione
Generally Available 06-30-2010
GGSN Features in Release 8.0
1-25
Network Controlled QoS (NCQoS)
This feature provides control of QoS for subscriber from network element side; i.e. GGSN.
It uses bearer control mode and Active Charging Services parameters to provide packet
filtering and other quality class identifier related configurations.
It uses bearer control mode and Active Charging Services parameters to provide packet
filtering and other quality class identifier related configurations.
Network-controlled QoS is the method by which the QoS for a PDP context (primary or
secondary) is updated on the request of the GGSN through Network Requested Update PDP
Context (NRUPC) message. It can also activate a new secondary PDP context on Network
Requested Secondary PDP Context Activation (NRSPCA) message from the GGSN.
secondary) is updated on the request of the GGSN through Network Requested Update PDP
Context (NRUPC) message. It can also activate a new secondary PDP context on Network
Requested Secondary PDP Context Activation (NRSPCA) message from the GGSN.
This feature requires separate license key.
For more details on configuration of this service, refer Dynamic QoS Renegotiation chapter
in System Enhanced Feature Configuration Guide.
in System Enhanced Feature Configuration Guide.
Traffic Shaping
This is an enhanced feature is a traffic rate limiting method similar to Traffic Policing,
however, shaping provides a buffer facility for packets exceeding the configured limit. Once
the packets exceed the data-rate, the packets queue inside the buffer to be delivered at a later
time.
however, shaping provides a buffer facility for packets exceeding the configured limit. Once
the packets exceed the data-rate, the packets queue inside the buffer to be delivered at a later
time.
The bandwidth enforcement can be done in the downlink and the uplink directions
independently. If there is no more buffer space available for subscriber data, the system can
be configured to either drop the packets or keep them for the next scheduled traffic session.
independently. If there is no more buffer space available for subscriber data, the system can
be configured to either drop the packets or keep them for the next scheduled traffic session.
This feature requires separate license key.
For details on configuring this service, refer to the Traffic Policing and Shaping chapter in
the System Enhanced Feature Configuration Guide.
the System Enhanced Feature Configuration Guide.
Direct Tunnel Support
Direct tunnel improves the user experience (e.g. expedited web page delivery, reduced
round trip delay for conversational services, etc.) by eliminating SGSN tunnel ‘switching’
latency from the user plane. An additional advantage of Direct Tunnel from an operational
and capital expenditure perspective is that direct tunnel optimizes the usage of user plane
resources by removing the requirement for user plane processing on the SGSN.
round trip delay for conversational services, etc.) by eliminating SGSN tunnel ‘switching’
latency from the user plane. An additional advantage of Direct Tunnel from an operational
and capital expenditure perspective is that direct tunnel optimizes the usage of user plane
resources by removing the requirement for user plane processing on the SGSN.
The Direct Tunnel architecture allows the establishment of a direct user plane tunnel
between the RAN and the GGSN, bypassing the SGSN. The SGSN continues to handle the
control plane signalling and typical makes the decision to establish Direct Tunnel at PDP
Context Activation. A Direct Tunnel is achieved at PDP context activation by the SGSN
establishing a user plane (GTP-U) tunnel directly between RNC and GGSN (using an
Update PDP Context Request towards the GGSN).
between the RAN and the GGSN, bypassing the SGSN. The SGSN continues to handle the
control plane signalling and typical makes the decision to establish Direct Tunnel at PDP
Context Activation. A Direct Tunnel is achieved at PDP context activation by the SGSN
establishing a user plane (GTP-U) tunnel directly between RNC and GGSN (using an
Update PDP Context Request towards the GGSN).
The following figure illustrates the working of direct Tunnel between RNC and GGSN.