Gy Interface Support
Features and Terminology ▀
Cisco ASR 5x00 Packet Data Network Gateway Administration Guide ▄
365
The purpose of this feature is to support Gy based data sessions in the event of an OCS outage. Diameter client allows
the user's data session to continue for some fixed quota and then retries the OCS server to restore normal functionality.
This feature adds more granularity to the existing failure handling mechanism.
With the implementation of this feature, Gy reporting during outages is supported. A temporary time and/or volume
quota is assigned to the user in the event of an OCS outage which will be used during the outage period.
When the OCS returns to service, the GW reports all used quota back to OCS and continues with normal Gy reporting.
For each DCCA-service, CLI control is available for the following options:
Interim quota volume (in bytes) and quota time (seconds). Both values will apply simultaneously, if configured
together and if either quota time or quota volume is exhausted, the Diameter client retries the OCS.
Option to limit the number of times a session can be assigned a temporary quota. If the user exceeds this amount,
the session will be terminated/converted to postpaid.
The quota value is part of the dcca-service configuration, and will apply to all subscribers using that dcca-service. The
temporary quota will be specified in volume (bytes) and/or time (seconds) to allow enforcement of both quota tracking
mechanisms individually or simultaneously.
When a user consumes the interim total quota or time configured for use during failure handling scenarios, the GW
retries the OCS server to determine if functionality has been restored. In the event that services have been restored,
quota assignment and tracking will proceed as per standard usage reporting procedures. Data used during the outage will
be reported to the OCS.
In the event that the OCS services have not been restored, the GW re-allocates the configured amount of quota and/or
time to the user. The GW reports all accumulated used data back to OCS when OCS is back online. If multiple retries
and interim allocations occur, the GW reports quota used during all allocation intervals. This cycle will continue until
OCS services have been successfully restored, or the maximum number of quota assignments has been exhausted.
Support for OCS unreachable CLI commands is added under Diameter Credit Control Configuration mode.
For the P-GW/XGW/GGSN, this behavior will apply to all APNs and subscribers that have online charging enabled by
the PCRF. In the HA, this behavior will apply to all users that have online charging enabled by the AAA. Settings will
be applied to the dcca-service.
In Release 15.0, the following enhancements are implemented as part of the Assume Positive Gy feature:
Configurable per error code treatment to enter assume positive mode
Graceful session restart upon receipt of a 5002 error
Important:
Note that the Graceful session restart feature is customer specific. For more information
contact your Cisco account representative.
Configurable per Error Code Treatment
This feature allows the customers to configure error result codes using the CLI command “
servers-unreachable
behavior-triggers
” that will trigger entering assume positive mode on the fly for CCR-Initial and CCR-Update
messages. CCR-Terminate message is currently not supported.
Any error result codes from the range 3xxx to 5xxx can be specified using the CLI commands. This feature has been
implemented to provide more flexibility and granularity in the way assume positive mode is triggered for error result
codes.
Graceful Session Restart
Graceful session restart upon receipt of a 5002 error code is supported for server retried CCR-U messages during
assume positive state. Also, any unreported usage from the time, server retried CCR-U sent till CCA-I is received, will
be reported immediately by triggering CCR-U with usages for the same.