Hi all, I've had a request to implement the History-Info header for a very particular purpose but I'm not sure if it is a valid use of this header. The basic need is to pass on PSTN redirection information to the target of an initial INVITE when a PSTN call is redirected to a SIP/PSTN gateway.
If such a call comes in to the gateway, is it a valid use of the History-Info header to insert this as a Reason in the initial INVITE? I.e. --- call redirected from PSTN ---> SIP Gateway -> INVITE -> [EMAIL PROTECTED] Where the INVITE will contain: History-Info: <tel:DialledNumber?Reason=Q.850%3Bcause%3DSomeQ850CauseCode>;index=1 Two items concern me: 1. Section 4.1 of RFC 4244 states: 'A reason is not included for a hi-targeted-to-uri when it is first added in a History-Info header, but rather is added when the retargeting actually occurs.' Here the retargeting occurs at the same time as when the target URI is first added as the retargeting is a result of activity on the PSTN. However, it is desired that this information be passed on to the UAS. Also, the hi-targeted-to-uri is not that of the target URI of the INVITE, it is that of a phone number on the PSTN. Can anybody clarify this? 2. There would be no 'Reason=SIP' in the header. Section 4.3.3.1.2 describes that there must always be a SIP Reason header contained within a History-Info header with an additional non-SIP Reason available as an option. I realise that this section is describing proxy behaviour and the gateway in question is a UA but there is no equivalent in the section describing UAC behaviour. Any thoughts? If there is another mechanism that would be more suited to this need I would like to hear about it. Any help much appreciated. Cheers Steve Steve Paterson Software Engineer Aculab Tel: +44 (0) 1908 273866 Fax: +44 (0) 1908 273801 Email: mailto:[EMAIL PROTECTED] Website: http://www.aculab.com Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales) P Please consider the environment and don't print this e-mail unless you really need to _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
