RE: [W3C BPWG] HTTP header fields X-* and normal ones / question

It seems the discussion is quickly drifting towards the 
optimal mode of operation of transformation proxies -- 
this is not the topic of the original request. 

The question is simple:

There is some technology deployed in the Internet that
makes use of X-* header fields. The W3C is considering
formalizing best practices for this technology,
introducing normal (i.e. non X- prefixed) header fields, 
and registering them at IANA. 

However, there are already commercial systems in 
production use that send these X- prefixed header
fields. Hence, we realize there might be a migration
period where both X- prefixed and non-prefixed fields
may coexist. 

Furthermore, RFC3864 specifies a procedure to register
HTTP header fields. It also pre-defines the set of 
statuses that a header field can have ("standard",
"informational", "historic", etc). There is an X-
prefixed field registerd (X-Archived-At) and marked
as "deprecated", and a corresponding non-prefixed
field Archived-At, permanently registered and marked
"standard". 

All this seems to indicate that the IETF has devised
a life-cycle management scheme for header fields. We
would be grateful to know more about it, especially
in the view of handling the coexistence of X- and 
non-X- prefixed fields, and the phasing out of 
deprecated fields.

As for how transformation proxies work, and why these
strange manipulations of HTTP header fields take place,
this would require a detailed exposition of their 
peculiarities, of the characteristics of mobile browsers, 
and of the specific practices of application development 
in the mobile Internet -- and this is not the right
forum for this.

Best regards


Eduardo Casais
areppim AG
Bern, Switzerland

Received on Friday, 23 January 2009 08:35:40 UTC