On Tue, 2005-08-09 at 10:19 +0300, Fortinsky Michael wrote: > I have a couple of questions about case-sensitivity in SIP. > Section 7.3.1 of RFC3261 states that tokens are always case-insensitive. > My questions relate specifically to the From/To tags and the branch > parameter (which I think are both types of tokens). > > (1) Should the From and To tags be considered case-sensitive or > case-insensitive? > e.g., are the following two tags considered to be equal: > > To: Bob <sip:[EMAIL PROTECTED]>;tag=a6c85cf > To: Bob <sip:[EMAIL PROTECTED]>;tag=A6C85CF > > (2) What about the branch parameter - is it considered case-sensitive or > case-insensitive? > And if it is considered case-insensitive, what about the magic > cookie defined at the start of a branch parameter. > Section 8.1.1.7 defines the magic cookie as "z9hG4bK"? > Is the value "Z9HG4BK" considered the same (and is it legal) ? > So for the branch, I can think of the following cases: > > (i) branch=z9hG4bK776asdhds > (ii) branch=z9hG4bK776ASDHDS > (iii) branch=Z9HG4BK776ASDHDS > > Are these all legal and considered equal?
Yes, but any implementation that changes the case of either tags or branch identifiers is just asking for interoperability problems. Compare them case-insensitive, but always copy them verbatim when constructing messages. I think that there should be an 'opaque-token' in the grammar that allows the same characters as 'token' but is defined to be case sensitive to avoid this issue. -- Scott Lawrence, Consulting Engineer Pingtel Corp. http://www.pingtel.com/ +1.781.938.5306 x162 or sip:[EMAIL PROTECTED] _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
