> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On > Behalf Of Paul Kyzivat > Sent: Thursday, November 15, 2007 9:24 AM > To: Amit Lobo > Cc: [email protected] > Subject: Re: [Sip-implementors] How to know active call > status,using SIP > > If I understand you the IPPBX is sitting in the middle of the > call, between the two endpoints and wants a way to verify > that the two endpoints continue to function. Right? > > If the IPPBX is a B2BUA then it may, at any time after the > call is established, send a request to either of the ends. > This could be OPTIONS, reINVITE, UPDATE, ...
Since I haven't heard anyone recently mention using OPTIONS to check dialog/call state, what should be returned if the dialog does not exist? (I'm assuming you were indicating sending OPTIONS within the dialog.) RFC 3261 section 11.1: "An OPTIONS request received within a dialog generates a 200 (OK) response that is identical to one constructed outside a dialog and does not have any impact on the dialog." Based upon the above text, I wouldn't think a UAS is obligated to return a failure response when the dialog does not exist. Since rfc5057 reiterated that the 481 was an inappropriate OPTIONS response since OPTIONS does not belong to any usage, is there an RFC which recommends sending an OPTIONS response to release the dialog? And if so, which response is recommended? (RFC 5057 just mentions those that could be used and none seem applicable.) _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
