Re: [tsvwg] I-D Action: draft-ietf-tsvwg-udp-options-31.txt

[Dan Wing <[e-mail]>]

In UDP, the only place I have seen this is TFTP, and SIP over UDP (for NATting as part of the ill-advised "ALG" that is widely available)  which is non-standard and BOOTP/DHCP (for DHCP relaying across broadcast domains) which is standard (RFC3046).  Perhaps there are others, but if so I agree it's a tiny, tiny set of IETF standards that allow or encourage modification of UDP payloads.

-d


> On Mar 5, 2024, at 5:57 PM, Tom Herbert <tom=[e-mail]> wrote:
> 
> Hi,
> 
> I don't understand the intent of this new text:
> 
> "Another reason is because APC may fail even where the user data has
> not been corrupted, such as when its contents have been overwritten.
> Such overwrites could be intentional and not widely known; defaulting
> to silent ignore ensures that option-aware endpoints do not change how
> users or applications operate unless explicitly directed to do
> otherwise."
> 
> I am not familiar with any IETF protocol that allows UDP payload to be
> updated in flight. In fact, RFC7605 states that UDP port numbers
> cannot be correctly interpreted in the network, so there is no way to
> implement a robust protocol that changes UDP payload inflight. Because
> of this, an intermediate node that is overwriting the UDP payload *is*
> in fact corrupting the UDP payload. So this new provision is seemingly
> accommodating this non-standard, potentially harmful behavior as the
> default.
> 
> Tom
> 
> On Mon, Mar 4, 2024 at 3:56 PM <[e-mail]> wrote:
>> 
>> Internet-Draft draft-ietf-tsvwg-udp-options-31.txt is now available. It is a
>> work item of the Transport and Services Working Group (TSVWG) WG of the IETF.
>> 
>>   Title:   Transport Options for UDP
>>   Author:  Joe Touch
>>   Name:    draft-ietf-tsvwg-udp-options-31.txt
>>   Pages:   52
>>   Dates:   2024-03-04
>> 
>> Abstract:
>> 
>>   Transport protocols are extended through the use of transport header
>>   options. This document extends UDP by indicating the location,
>>   syntax, and semantics for UDP transport layer options.
>> 
>> The IETF datatracker status page for this Internet-Draft is:
>> https://datatracker.ietf.org/doc/draft-ietf-tsvwg-udp-options/
>> 
>> There is also an HTMLized version available at:
>> https://datatracker.ietf.org/doc/html/draft-ietf-tsvwg-udp-options-31
>> 
>> A diff from the previous version is available at:
>> https://author-tools.ietf.org/iddiff?url2=draft-ietf-tsvwg-udp-options-31
>> 
>> Internet-Drafts are also available by rsync at:
>> rsync.ietf.org::internet-drafts
>> 
>> 
>