Cisco Cisco Packet Data Gateway (PDG) Guida Alla Risoluzione Dei Problemi
QoS Management
Dynamic QoS Renegotiation ▀
Cisco ASR 5000 Series Enhanced Feature Configuration Guide ▄
OL-22983-01
Dynamic QoS Renegotiation
Dynamic QoS Renegotiation minimizes the risk of bandwidth mis-appropriation. This feature allows the GGSN to
analyze application traffic, and trigger QoS renegotiation with the SGSN to optimize service performance.
analyze application traffic, and trigger QoS renegotiation with the SGSN to optimize service performance.
In Dynamic QoS Renegotiation, the GGSN performs packet inspection of application traffic to detect the type of service
being utilized and automatically renegotiates the QoS to the appropriate level with a maximum QoS level corresponding
to the level granted by the HLR. QoS renegotiation is performed by sending an update PDP context request to the
SGSN. This solution is optimal since the appropriate QoS level is always granted to the subscriber without any
requirement on the handset or on the core network. The only prerequisite is QoS renegotiation support on the SGSN. In
this model, over reservation of radio resources is avoided, while maintaining the appropriate bandwidth for subscribers
with real requirements.
being utilized and automatically renegotiates the QoS to the appropriate level with a maximum QoS level corresponding
to the level granted by the HLR. QoS renegotiation is performed by sending an update PDP context request to the
SGSN. This solution is optimal since the appropriate QoS level is always granted to the subscriber without any
requirement on the handset or on the core network. The only prerequisite is QoS renegotiation support on the SGSN. In
this model, over reservation of radio resources is avoided, while maintaining the appropriate bandwidth for subscribers
with real requirements.
The ST16 and ASR 5000 supports L7 stateful analysis and QoS Renegotiation. Combining these functionalities results
in Dynamic QoS Renegotiation. The system also generates CDRs (or real time charging information) that includes the
current QoS information and the service accessed. This enables intelligent application-based charging of services, taking
into account the granted QoS. It also enables rebates when it was not possible to provide the QoS level required by an
application.
in Dynamic QoS Renegotiation. The system also generates CDRs (or real time charging information) that includes the
current QoS information and the service accessed. This enables intelligent application-based charging of services, taking
into account the granted QoS. It also enables rebates when it was not possible to provide the QoS level required by an
application.
Important:
For L7 traffic analysis ECSv2 license is required.
How Dynamic QoS Renegotiation Works
Implementation of Dynamic QoS Renegotiation involves the following:
Initial QoS
Service Detection
Classification of Application Traffic
Quality of Service Renegotiation
Initial QoS
When the session is established, an initial level of QoS must be assigned to the subscriber. The GGSN may either grant
the requested QoS, or grant a lower QoS level (minimum or intermediate level). The initial QoS remains in effect until
the SGSN or GGSN requests a change. When Dynamic QoS Renegotiation is enabled, there are several conditions when
the system would request a QoS change.
the requested QoS, or grant a lower QoS level (minimum or intermediate level). The initial QoS remains in effect until
the SGSN or GGSN requests a change. When Dynamic QoS Renegotiation is enabled, there are several conditions when
the system would request a QoS change.
Services detected that do not need high QoS: After a configurable time period of a subscriber having terminated
services that require high QoS, the system could lower the QoS to a value more appropriate to the services
actually being used.
actually being used.