Re: Is forwarding hop-by-hop headers a MUST-level violation?

On Mon, 12 Jul 2004, Jamie Lokier wrote:

> Alex Rousskov wrote:
> > I do not see a compelling reason to make an exception for
> > Transfer-Encoding. Do you?
>
> Yes.  The reason is similar to making an exception for Connection.
> Any agent which parses and understands Connection (i.e. to filter out
> named headers) _must_ also understand and parse Transfer-Encoding, as
> it determines the message boundary.

Understanding message boundary is often independent of forwarding
headers. An implementation may have no problem isolating the message,
but may still forward the Transfer-Encoding hop-by-hop header (which
may or may not represent encoding for the next hop). Caching proxies
are especially vulnerable to this because their client-side code is
often rather different/isolated from the server-side code.

Alex.