Re: [tsvwg] New Version Notification for draft-herbert-udp-space-hdr-01.txt

[Joe Touch <[e-mail]>]

On 2019-07-10 11:36, Tom Herbert wrote:

> ... 
> The UDP surplus header provides alignment,

UDP options already has NOPs for that. 

> integrity check,

UDP options already has a OCS for that. 

> disambiguation for other uses of surplus space,

This isn't needed. It won't support existing uses (not that any are
known) because they won't follow the format.  UDP options already allows
for experimental uses and other standards-track extensions through
codepoint assignment. 

> a means to extend the UDP header,

Actually, it hinders UDP options by limiting them to 1020 bytes, as with
all "other uses". 

> friendliness with HW and SW implentations,

It has no benefit vs. the existing approach in this regard. 

> extensibility,

It's actually less extensible than doing things within the current UDP
options, due to the end alignment requirement and length limit per type.


> uniformity with the other notable transport protocol that contains options,

UDP options tracks TCP options much more closely. 

> addresses the requirements for UDPv6 checksum without having to invoke RFC6939.

There are many ways to address this as have already been proposed - but
we're not talking about them. We're wasting time debating this instead. 

> Overhead is four bytes (seven with worse case padding) which is insignificant compared to the benefits.

There are no benefits (as noted above), only detriments IN ADDITION to
the overhead. 

Can we please discuss more useful topics? 

Joe