Packetizer

Full Response to Lightweight RRQ (Q22)


The information in this article applies to: H.323, H.225.0

In a lightweight RRQ, as opposed to a full RRQ, only some fields are used while the rest are ignored by the GK, hence the name, “lightweight RRQ.” However, H.225.0 does not say whether all of the fields are used in the RCF that the GK sends in response to a lightweight RRQ. An EP must abide by whatever parameters the GK provides in all RCFs. However, this could present some interesting problems if the GK decides to change a field unrelated to the keep-alive nature of an RCF response. My recommendation is that a GK respond to a lightweight RRQ with an RCF containing the same values as the original, non-lightweight, registering RCF with the following exceptions: requestSeqNum and timeToLive. IOW, the GK should only change these fields. If the GK wants to change some aspect of the EP registration, it should disengage any established calls with the EP and send URQ with reason, reregistrationRequired. When the EP reregisters, the GK can provide the changed data in a new, full RCF.