I'm doing some integration toward Gy client (PCEF), and encountered an unclear area. I'm not sure if it is unclear in RFC 4006 or the 3GPP TS32.299 or both.
Scenario: A user logs on. The user has no credit left for a rating-group 42.
CCR-initial and CCA-initial:
Nothing interesting. In Gy it is typically just "empty" requests for the purpose of registering the user session.
The user then attempts to use rating-group 32:
CCR-update:
Multiple-Services-Credit-Control {
Rating-Group = 42
Requested-Service-Unit {
}
}
to which the OCS (Gy server) would normally respond:
CCA-update:
Result-Code = 2001 (success)
Multiple-Services-Credit-Control {
Rating-Group = 42
Result-Code = 4012 (credit-limit-reached)
Final-Unit-Indication {
...
}
}
However, the Gy specification says that a zero-grant is needed, which to me sounds a bit odd, but nevertheless:
Result-Code = 2001 (success)
Multiple-Services-Credit-Control {
Rating-Group = 42
Result-Code = 4012 (credit-limit-reached)
Granted-Service-Unit {
CC-Total-Octets = 0
}
Final-Unit-Indication {
...
}
}
Now, the Gy client vendor says that the result-code inside the MSCC must be 2001 (success). It sort of makes sense because there is a grant.
But that made me wonder: In which case would result-code=4012 make sense? Is it just 3GPP who has "mangled" diameter-credit-control in the Gy application?