There is a "token" value which is passed from a policy server to a UA. The token value is the content of a <token> element in the session-info document, so in general it is a sequence of Unicode characters. The UA uses it when it makes certain requests by adding a Policy-Info header of the form: Policy-Info: sip:foo@xxxxxxxxxxx;token=xyzzy where the value of the "token" parameter is the content of the <token> element in the session-info that it was given. The question is what characters are permitted in the token value? The only limitation on the session-info document is that it consist of Unicode characters. But in order to put it in a parameter value, it must be representable there. Parameter values use %-escaping, so characters from U+0020 (space) to U+007E (~) can easily be accommodated. If we use %80 to %FF to represent the characters from U+0080 to U+00FF, we can add the Latin-1 set. Or we could assume that %-escaping is used to encode *bytes* used in the *UTF-8* representation of characters, in which case the entire Unicode set is representable. (Since the semantics of %-escaping is not described anywhere in RFC 3261, either of these is possible.) It seems to me that limiting the characters to U+0020 through U+007E, the ordinary ASCII set, is enough flexibility and avoids all sorts of complications. Dale _______________________________________________ Sipping mailing list https://www.ietf.org/mailman/listinfo/sipping This list is for NEW development of the application of SIP Use sip-implementors@xxxxxxxxxxxxxxx for questions on current sip Use sip@xxxxxxxx for new developments of core SIP
