On Wed, May 13, 2009 at 3:06 PM, Miklos Tirpak miklos@iptel.org wrote: (snip)
This patch increases the compatibility with non-standard implementations when the parameters are added to the end of the sip: URI instead of the userinfo part in case of a tel: URI embedded in a sip: URI. For example: sip:123@domain;foo=bar;user=phone instead of sip:123;foo=bar@domain;user=phone
Despite that RFC 3261, Section 19.1.6 states that when a TEL URI (RFC 2806) is converted to a SIP URI, the entire telephone-subscriber portion of the TEL URI, _including any parameters_, should be placed into the userinfo part of the SIP URI, deployment experiences showed that this may raise some interoperability issues: basically, there are good chances that one network element will strip or will be unable to parse userinfo parameters.
For the sake of completeness, a typical use case would be number portability-related information in the SIP URI (RFC4694 only addresses the TEL URI), where some elements support/carry them as URI-userinfo parameters (as defined per RFC 3261) while others do so as URI parameters.
Cheers,