Re: [Sip-implementors] 200 OK Retransmission
onewhoknows writes: > I have an issue with some older releases of Asterisk talking to an Avaya > PBX. > > I think there's a network issue somewhere, but in the meantime, I'd like to > know which side is handling the following transaction correctly: > > Asterisk > Avaya > Invite > > < 100 Trying > < 200 OK >> ACK > < 200 OK > < 200 OK > < 200 OK > ... several more times > < 200 OK > < BYE >> 200 OK > > The issue is intermittent and when it occurs, the far end does not see the > ACK. > > My question in this particular instance is should Asterisk be responding to > each 200 OK with an ACK, or has it satisfied its part of the transaction by > sending that first ACK? Each 200 OK has the same CSEQ, branch, etc. Every 200 that the UAC receives, it must answer with an ACK. See RFC 3261 section 13.2.2.4, "The UAC core MUST generate an ACK request for each 2xx received from the transaction layer.", etc. Dale ___ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
Re: [Sip-implementors] 200 OK Retransmission
On 1/3/18 7:54 PM, onewhoknows wrote: Hello, I have an issue with some older releases of Asterisk talking to an Avaya PBX. I think there's a network issue somewhere, but in the meantime, I'd like to know which side is handling the following transaction correctly: Asterisk > Avaya Invite > < 100 Trying < 200 OK ACK < 200 OK < 200 OK < 200 OK ... several more times < 200 OK < BYE 200 OK The issue is intermittent and when it occurs, the far end does not see the ACK. My question in this particular instance is should Asterisk be responding to each 200 OK with an ACK, or has it satisfied its part of the transaction by sending that first ACK? Each 200 OK has the same CSEQ, branch, etc. Asterisk is wrong. The ACK must be transmitted for each 200 OK received. This is necessary in the case where an ACK is lost. The UAS is retransmitting the 200 because it hasn't yet received an ACK. You say this is intermittent, which is consistent with an ACK being lost. Thanks, Paul ___ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
[Sip-implementors] 200 OK Retransmission
Hello, I have an issue with some older releases of Asterisk talking to an Avaya PBX. I think there's a network issue somewhere, but in the meantime, I'd like to know which side is handling the following transaction correctly: Asterisk > Avaya Invite > < 100 Trying < 200 OK > ACK < 200 OK < 200 OK < 200 OK ... several more times < 200 OK < BYE > 200 OK The issue is intermittent and when it occurs, the far end does not see the ACK. My question in this particular instance is should Asterisk be responding to each 200 OK with an ACK, or has it satisfied its part of the transaction by sending that first ACK? Each 200 OK has the same CSEQ, branch, etc. Thanks! ___ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
