Re: Comments on RFC2806bis

> Actually, I can think of a number of situations in which an identifier
> can be used for different objects.
> 
> The context is a qualifier on the applicability of the URI. It's not
> really more than one parameter - The single parameter 'phone-context' can
> have more than one value. This can happen due to introduction of relief 
> codes,
> or the Vienna case, where there are two codes to dial Vienna (within 
> Austria).
> Thus a Viennese phone could have two values for its phone context (01 
> and the
> 
> Any ideas on value separators - is the above an exhaustive list?

I agree that multiple contexts are useful. The choice of separators is

Systematically, from RFC 2396

delims      = "<" | ">" | "#" | "%" | <">

are out, as are

  unwise      = "{" | "}" | "|" | "\" | "^" | "[" | "]" | "`"

The best set to draw from is

  reserved    = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" |
                     "$" | ","

as they are meant for delineation. For tel URLs, ";", "+", "=" are 
taken. I was wrong about the comma - it's a legitimate separator. I 
suspect I got confused by the difficulty that this sometimes causes in 
Contact and To/From SIP headers, requiring <> enclosure.

 From the set, "&" or "," seem the most semantically meaningful. May as 
well use the comma.

> BTW, James, the conclusion we had was that a RN is not in International 
> format
> so that a local number is OK when using HEXDIG. I can't think of a 
> situation
> where one needs a "pseudo-E.164" number with HEXDIG in the 
> country/service code.
> Was this your intention?
> 
> atb,
>   Lawrence