[SIPForum-discussion] Clarification regarding the presence of angle brackets for SIP URI in From/To/Contact Header

[Keerthi]

Hi All,

I need a clarification regarding the presence of angle brackets for SIP URI in From/To/Contact
headers.

The RFC 3261 says, 

When the header field value contains a display name, the URI including all URI parameters
is enclosed in "<" and ">". If no "<" and ">" are present, all parameters after the URI are 
header parameters, not URI parameters. The display name can be tokens, or a quoted string, 
if a larger character set is desired.

>From this i understood that, if 'display-name' is not present then, 
SIP URI will not have "<,>" in From/To/Contact headers.

But the example given below confuses me, even there is no display name it has "<,>", 
with header parameter.

Examples in RFC 3261,

m: <sips:bob at 192.0.2.4>;expires=60

Please explin me, when the SIP URI will have "<,>".

Thanks in advance!!! 

-- 
Regards,
Keerthi.