Cisco Cisco ASR 5000
Support For QoS Upgrade From GGSN or PCRF
▀ How it Works
▄ SGSN Administration Guide, StarOS Release 18
2. The Create PDP Context Response arrives from the GGSN. If the configuration for “Upgrade QoS Supported”
flag is enabled under the APN-Profile, the GGSN requested QoS is handled.
A CLI option is provided to enable or disable the keyword
prefer-as-cap subscription
. Based on the
configuration of this keyword, the following QoS processing occurs:
The keyword
prefer-as-cap subscription
is disabled: The SGSN accepts the QoS in the Create PDP
Context Response as the Negotiated QoS. In an ideal 2G scenario where all the parameters are configured
appropriately at the GGSN/PCRF, an upgrade beyond “472” kbps does not occur. If the GGSN sends QoS
greater than “472” kbps, this requested bitrate is capped to “472” kbps.
appropriately at the GGSN/PCRF, an upgrade beyond “472” kbps does not occur. If the GGSN sends QoS
greater than “472” kbps, this requested bitrate is capped to “472” kbps.
The keyword
prefer-as-cap subscription
is enabled: The SGSN negotiates the QoS received in the
Create PDP Context Response with the Subscribed QoS. After negotiation if the QoS is downgraded, the
“Upgrade QoS Supported” flag not set in the Update PDP Context Request message.
“Upgrade QoS Supported” flag not set in the Update PDP Context Request message.
The “Upgrade QoS Supported” flag for Update PDP Context Request and Response
If support to send “Upgrade QoS Supported” flag is configured under the APN-Profile and “No QoS negotiation' flag is
not set, the SGSN sets the “Upgrade QoS Supported” flag while sending the Update PDP Context Request. The
“Upgrade QoS Supported” flag is not set in every Update PDP Context Request, for example, in preservation and direct
tunnel this flag is not set in Update PDP Context Request message. The relationship between the “No QoS negotiation”
flag and the “Upgrade QoS Supported” flags in Update PDP Context Request messages is summarized as:
not set, the SGSN sets the “Upgrade QoS Supported” flag while sending the Update PDP Context Request. The
“Upgrade QoS Supported” flag is not set in every Update PDP Context Request, for example, in preservation and direct
tunnel this flag is not set in Update PDP Context Request message. The relationship between the “No QoS negotiation”
flag and the “Upgrade QoS Supported” flags in Update PDP Context Request messages is summarized as:
If “No QoS negotiation” flag is set, the “Upgrade QoS Supported” flag is not set.
If “No QoS negotiation” flag is not set, the “Upgrade QoS Supported” flag is set.
A CLI option is provided to enable or disable the keyword
prefer-as-cap subscription
. Based on the
configuration of this keyword, the following QoS processing occurs:
The keyword
prefer-as-cap subscription
is disabled: The SGSN accepts the QoS in the Create PDP
Context Response as the Negotiated QoS. This Negotiated QoS can be downgraded by the RNC during RAB
assignment. If the RNC downgrades the QoS then “Upgrade QoS Supported” flag is not set in the
corresponding Update PDP Context Request message.
assignment. If the RNC downgrades the QoS then “Upgrade QoS Supported” flag is not set in the
corresponding Update PDP Context Request message.
The keyword
prefer-as-cap subscription
is enabled: The SGSN negotiates the QoS received in the
Create PDP Context Response with the Subscribed QoS. After negotiation if the QoS is downgraded, the
“Upgrade QoS Supported” flag not set in the Update PDP Context Request message.
“Upgrade QoS Supported” flag not set in the Update PDP Context Request message.