If a UAS is in DND mode (DontDisturb) it will reply "480" (or 486/603) for an incoming INVITE.
Of course sending an INVITE is not a valid way to know the UAS status since INVITE will make ring the phone, create a "missed call" in phone GUI and so. Theorically if an UAS in DND mode receives a OPTIONS it should reply with the same as in case of INVITE, so sending an OPTIONS would be valid to know the status of the UAS: 11.2 Processing of OPTIONS Request The response to an OPTIONS is constructed using the standard rules for a SIP response as discussed in Section 8.2.6. The response code chosen MUST be the same that would have been chosen had the request been an INVITE. That is, a 200 (OK) would be returned if the UAS is ready to accept a call, a 486 (Busy Here) would be returned if the UAS is busy, etc. This allows an OPTIONS request to be used to determine the basic state of a UAS, which can be an indication of whether the UAS will accept an INVITE request. Unfortunatelly just a few SIP devices implement this behaviour: - Thomson S2030 always reply 200. - Linksys seems to do the same. Is it really extended? I'm doing a script to check the status of phones so I need OPTIONS working with the real status of phones (this is, receiving the same reply as it the request is an INVITE). Thanks for any comment. -- Iñaki Baz Castillo [EMAIL PROTECTED] _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
