introduction of QoS selection based on RAT type, several QoS profiles can now
be configured and associated with the APN profile with the access type marked
as either GPRS or UMTS.
Listed below are the
SGSN functions now supported for QoS selection:
QoS based on RAT type
QoS based on PLMN, this configuration automatically happens as the Operator
policy is PLMN based. The QoS Profile is configured on RAT basis.
support for configuring APN-AMBR and UE-AMBR per RAT Type.
The SGSN supports
configuring all the R99 QoS parameter under the APN profile except for Traffic
class. It also supports configuring the R97 QoS parameters namely Delay Class,
Reliability class, Peak throughput, Precedence class and Mean Throughput. This
configuration is used to over-ride the HLR provided Subscribed QoS value or the
configured values are used in combination with subscribed values.
QoS capping has to
be performed at various levels like the RAT-Type and PLMN. To achieve QoS
capping at different levels, the QoS parameters under the APN profile are also
made available under a new profile called the "QoS-profile". The QoS-profile
also provides support for over-riding the R97 QoS parameters, Traffic class,
UE-AMBR and the APN-AMBR (UE-AMBR and APN-AMBR applicable only for S4-SGSN).
This feature enhancement supports backward compatibility.
The QoS Profile can
be associated with the APN profile, for each access-type independently or as
common to profile.
At the APN profile
level, if QoS parameters (R99 parameters except traffic class) as well as a QoS
profile are configured, then the QoS profile takes precedence over the QoS
QoS parameters in
QoS profile and APN profile are identical. The new QoS profile provides the
modular approach in configuring QoS parameters and associate it to APN Profile
per RAT Type.
QoS profile also
provides an additional configuration (when compared to apn-profile) named
"prefer-tc". This configuration allows the operator to override the Traffic
class received in Subscription. "prefer-tc" works closely with "prefer-as-cap"
"prefer-as-cap" is set to both subscription and local then SGSN will negotiate
the traffic class configured to traffic class subscribed. Further QoS
parameters under this traffic class will be negotiated.
"prefer-as-cap" is set to local then QoS parameters under local configuration
will be negotiated with requested for QoS capping.
configures "prefer-tc" then he is expected to configure all the QoS parameters
of all traffic class under QoS profile.