ACK

Click on the red underlined text to get to the source

... above. The call flow of Figure 1 shows an INVITE-200 OK-ACK handshake between a UAC ...

... |(6)200 OK(c) |<------------| | |<------------| | | | | (7)ACK(c) | | |-------------------------->| (8) ACK | ...

... | | (7)ACK(c) | | |-------------------------->| (8) ACK | | | |------------>| | | | | ...

... sigcomp parameter. (7) ACK UAS Via: UAC ...

... The UAC sends the ACK (7) compressed directly to P2 (P1 did not Record-Route). ...

... Record-Route). (8) ACK UAS Via: P2 ...

... sigcomp P2 sends the ACK (8) uncompressed to the UAS. ...