Subject: Inconsistency regarding use of Allow header

From: "Gary Cote" <[email-masked]>
Date: Thu, 2 Dec 1999 08:59:48 -0800

Please pardon if this has been discussed before. I did not see any reference
to it in the mail archive, or in the SIP notes and clarifications page.

RFC2543, Section 6 contains a table summarizing the use of various header
fields. It indicates that the Allow header is mandatory for responses to the
OPTIONS method, and optional for all 405 (Method Not Found) responses.

This appears to be inconsistent with other references to the Allow header.
Sections 4.2.3 and 6.10 contradict the table - in effect stating the exact
opposite.

I'm guessing that the table is inaccurate, most likely due to a typo. Could
somebody please confirm for me?

Thanks.

--
Gary Cote
AWARD Solutions, Inc.
972-664-0727 x229

---

From: Jonathan Rosenberg <[email-masked]>
Date: Fri, 03 Dec 1999 23:48:04 -0500

Why is it inconsistent? 4.2.3 says:

> 600 (Busy). Such a server SHOULD return an Allow header field
>    indicating the methods that it supports. Proxy and redirect servers
>    simply forward the request without indicating their capabilities.

So, this is saying Allow is in the response to OPTIONS, as the table
says.

Section 6.10 does say something different:

> 6.10 Allow
> 
>    The Allow entity-header field lists the set of methods supported by
>    the resource identified by the Request-URI. The purpose of this field
>    is strictly to inform the recipient of valid methods associated with
>    the resource. An Allow header field MUST be present in a 405 (Method
>    Not Allowed) response and SHOULD be present in an OPTIONS response.

This says its a MUST in the 405 response, whereas the table says
optional in the response. This also says SHOULD in the OPTIONS response,
but the table says mandatory. These need to be made consistent, but they
are not opposites.

-Jonathan R.

-- 
Jonathan D. Rosenberg                       200 Executive Drive
Chief Scientist                             Suite 120 
dynamicsoft                                 West Orange, NJ 07052
[email-masked]                     FAX:   (732) 741-4778
http://www.cs.columbia.edu/~jdrosen         PHONE: (732) 741-7244
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