Re: A problem with RFC 6465's Uniform Format for Extension Headers

[Thomas Narten <[e-mail]>]

At Wed, 05 Feb 2014 01:25:03 -0300, Fernando Gont wrote:
> 1) If this problem remains un-addressed, then it's impossible to
> differentiate between new upper-layer headers (e.g. a new transport
> protocol) and new extension headers. Since such new extension headers
> might be leveraged for malicious purposes, the end-result is that
> middle-boxes are going to block *everything* (see RFC7045), which means:
> 
>   + no new extension headers
>   + no new transport protocols
> 
> ... so I think we really don't want to go there.

But we are already there. Folk won't deploy anything other than
TCP/UDP because NAT won't deal with it. That has already been reality
and is the reason that other or new transport protocols appear to be
virtually undeployable today.

Reality is that existing middleboxes tend to process what they
understand and have been explicitely coded to deal with. They just
punt on anything else because that is the easiest/safest thing to do.

I see little that we can do to change that.

Thomas