Subject: Content-Encoding vs. Content-Transfer-Encoding

From: "Joshua Moloney" <[email-masked]>
Date: Thu, 24 Feb 2000 15:15:18 -0000

Hi all,

I have a question about the "Content-Encoding" entity header.
Why is the MIME "Content-Transfer-Encoding" header defined in RFC 2045 not
used instead?
Am I correct in assuming that they do the same job?

For example, what headers should I include on a message with an
"application/ISUP" message body? :-

Content-Type: application/ISUP
Content-Transfer-Encoding: binary
.....

OR

Content-Type: application/ISUP
Content-Encoding: binary
.....

Thanks in advance,

Josh Moloney

Nortel Networks
[email-masked]

---

From: Jonathan Rosenberg <[email-masked]>
Date: Fri, 25 Feb 2000 14:16:36 -0500

The Content-Transfer-Encoding header was primarily meant to allow
message bodies to be transformed into formats that could be transferred
on channels that were not 8 bit clean. HTTP, which makes use of many of
the MIME headers, is 8 bit clean, and thus did not need
Content-Transfer-Encoding. SIP followed suit, and so does not use it
either. Content-Encoding is used for things like compression, which is
different (in fact, the opposite, since conversion of a binary file to a
7 bit transfer channel INCREASES the size of the body). 

-Jonathan R.

> Joshua Moloney wrote:
> Why is the MIME "Content-Transfer-Encoding" header defined in RFC 2045
> not used instead?

-- 
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