Route
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... the parameter comp=sigcomp to its URI in the Record-Route header
field.
If a user agent client ...
... sigcomp
parameter is obtained from a Record-Route header field when the
dialog is established. A client ...
... requests in the other direction) proxies need to rewrite their
Record-Route entries in the responses. A proxy performing Record-
Route ...
... Record-Route entries in the responses. A proxy performing Record-
Route inspects the Record-Route header field in the response and the
Contact header field ...
... proxy performing Record-
Route inspects the Record-Route header field in the response and the
Contact header field in the request that triggered this response (see
...
... upstream
(closer to the user agent client) hop in the route set. If this URI
contains the parameter comp=sigcomp ...
... proxy SHOULD add
comp=sigcomp to its entry in the Record-Route header field. If this
URI does not contain the parameter comp=sigcomp ...
...
Although proxies usually add zero or one Record-Route entries to a
particular request, some proxies add two of them to avoid Record-
...
... particular request, some proxies add two of them to avoid Record-
Route rewriting. A typical example of double Record-Routing is a SIP
...
... interface by the proxy. The proxy adds one Record-Route
entry for one interface and a second one for the other interface ...
... interface.
This way, the proxy does not need to rewrite the Record-Route header
field on the response.
Proxies ...
...
P2 receives the 200 OK response. P2 Record-Routed, so it inspects
the Route set for this dialog. For requests from the UAS towards the
UAC ...
... header field of the INVITE, because P1 did not
Record-Route. That Contact identified the UAC:
...
... INVITE), P2 assumes that the UAC would also like to send compressed
requests (Record-Route of the 200 OK). Therefore, P2 modifies its
entry in the Record-Route header field of the 200 OK (5). In the
...
... requests (Record-Route of the 200 OK). Therefore, P2 modifies its
entry in the Record-Route header field of the 200 OK (5). In the
INVITE (3), P2 did not used the comp=sigcomp ...