On 1/2/13 9:29 AM, Brett Tate wrote: >> On 12/28/12 8:45 AM, Theo Zourzouvillys wrote: >>> On Tue, Dec 18, 2012 at 4:24 PM, Paul Kyzivat <[email protected]> >> wrote: >>>> I don't think so. But maybe others will find a justification for >> doing so. >>> >>> I don't think it is valid - although it's totally underspecified. >>> >>> user=phone implies the user portion is a tel URI, and >>> tel:anonymous.invalid;phone-context=+1 isn't legitimate - so i can >> see >>> why a parser would fail it, as even if it was matching a >>> local-phone-number only hex digits would be allowed. >> >> Yeah, that makes some sense. >> >> 3261 is indeed underspecified about this. What it says is: >> >> The user URI parameter exists to >> distinguish telephone numbers from user names that happen to >> look like telephone numbers. If the user string contains a >> telephone number formatted as a telephone-subscriber, the >> user >> parameter value "phone" SHOULD be present. >> >> It doesn't ever say the flip of that: "If the user parameter value >> "phone" is present, the user string (SHOULD/MUST?) be formatted as a >> telephone-subscriber". >> >> If that is not so, then the parameter doesn't have a lot of value. > > I agree that RFC 3261 is underspecified. RFC 2543 was a little more clear. > > "If the host is an Internet telephony gateway, the user field > MAY also encode a telephone number using the notation of > telephone-subscriber (Fig. 4). The telephone number is a special > case of a user name and cannot be distinguished by a BNF. Thus, > a URL parameter, user, is added to distinguish telephone numbers > from user names. The phone identifier is to be used when > connecting to a telephony gateway. Even without this parameter, > recipients of SIP URLs MAY interpret the pre-@ part as a phone > number if local restrictions on the name space for user name > allow it."
Yes, 3261 did not improve on this. I will still argue that <sip:[email protected];user=phone> means that *servers responsible for example.com* should interpret the user part as a phone number. Servers for *other domains*, according to 2543 and 3261, are only concerned with the domain when routing the request. So for example they are *not* permitted to extract the phone number and use it to sent the request over a PSTN gateway. (This of course leaves a lot of wiggle room about which domains a server is "responsible for".) Thanks, Paul _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
