When two PUBLISH requests are received one after each other, it may happen that the second received PUBLISH will generate a NOTIFY before the first received PUBLISH is able to generate it's NOTIFY.
The normal behavior is like this:
--PUBLISH(1)-->|--NOTIFY(1)(Cseq=N)-->
--PUBLISH(2)-->|--NOTIFY(2)(Cseq=N+1)-->
Under the race condition, it lloks like this:
--PUBLISH(1)-->|--NOTIFY(2)(Cseq=N)-->
--PUBLISH(2)-->|--NOTIFY(1)(Cseq=N+1)-->
This leads to an inconsistent client notification.
Regards,
Ovidiu Sas