Gy Interface Support
▀ Features and Terminology
▄ Cisco ASR 5x00 Packet Data Network Gateway Administration Guide
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Quota Hold Time: The server can specify an idle timeout associated with a granted quota using the Quota-
Holding-Time AVP. If no traffic associated with the quota is observed for this time, the client understands that
the traffic has stopped and the quota is returned to the server. The client starts the quota holding timer when
quota consumption ceases. This is always when traffic ceases, i.e. the timer is re-started at the end of each
packet. It applies equally to the granted time quota and to the granted volume quota. The timer is stopped on
sending a CCR and re-initialized on receiving a CCA with the previous used value or a new value of Quota-
Holding-Time if received.
Alternatively, if this AVP is not present, a locally configurable default value in the client is used. A Quota-
Holding-Time value of zero indicates that this mechanism is not used.
Quota Validity Time: The server can optionally send the validity time for the quota during the interrogation with
the client. The Validity-Time AVP is present at the MSCC level and applies equally to the entire quota that is
present in that category. The quota gets invalidated at the end of the validity time and a CCR-Update is sent to
the server with the Used-Service-Units AVP and the reporting reason as VALIDITY_TIME. The entire quota
present in that category will be invalidated upon Quota-Validity-Time expiry and traffic in that category will
be passed or dropped depending on the configuration, till a CCA-Update is received with quota for that
category.
Validity-Time of zero is invalid. Validity-Time is relative and not absolute.
Volume Quota
The server sends the CC-Total-Octets AVP to provide volume quota to the subscriber. DCCA currently supports only
CC-Total-Octets AVP, which applies equally to uplink and downlink packets. If the total of uplink and downlink
packets exceeds the CC-Total-Octets granted, the quota is assumed to be exhausted.
If CC-Input-Octets and/or CC-Output-Octets is provided, the quota is counted against CC-Input-Octets and/or CC-
Output-Octets respectively.
Important:
Restricting usages based on CC-Input-Octets and CC_Output-Octets is not supported in this release.
Units Quota
The server can also send a CC-Service-Specific-Units quota which is used to have packets counted as units. The number
of units per packet is a configurable option.
Granting Quota
Gy implementation assumes that whenever the CC-Total-Octets AVP is present, volume quota has been granted for both
uplink and downlink.
If the Granted-Service-Unit contains no data, Gy treats it as an invalid CCA.
If the values are zero, it is assumed that no quota was granted.
If the AVP contains the sub AVPs without any data, it is assumed to be infinite quota.
Additional parameters relating to a category like QHT, QCT is set for the category after receiving a valid volume or
time grant.
If a default quota is configured for the subscriber, and subscriber traffic is received it is counted against the default
quota. The default quota is applicable only to the initial request and is not regranted during the course of the session. If
subscriber disconnects and reconnects, the default quota will be applied again for the initial request.
Requesting Quota
