Re: The TCP and UDP checksum algorithm may soon need updating

Michael Thomas <mike@mtcc.com> Sun, 07 June 2020 22:28 UTC

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Subject: Re: The TCP and UDP checksum algorithm may soon need updating
To: Joseph Touch <touch@strayalpha.com>
Cc: ietf@ietf.org
References: <28A2725D-00F8-4739-8A73-ED176F8EF561@strayalpha.com> <3AA98081-A70E-4076-8096-79FFAEE8A738@huitema.net> <830b91c4-0bb5-af5b-f7b8-c5edd43dc87e@mtcc.com> <4512C1BF-5722-479B-8506-24018610BEAD@strayalpha.com>
From: Michael Thomas <mike@mtcc.com>
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Date: Sun, 7 Jun 2020 15:28:34 -0700
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On 6/7/20 3:20 PM, Joseph Touch wrote:
> TLS isn’t “transport layer”. It’s app-layer.
>
> TCP-AO is transport layer - and would similarly protect against middlebox modifications.

That's my point: TLS leaves the transport layer unprotected.

Mike

>
> Joe
>
>> On Jun 7, 2020, at 2:16 PM, Michael Thomas <mike@mtcc.com> wrote:
>>
>>
>> On 6/7/20 12:39 PM, Christian Huitema wrote:
>>>> On Jun 7, 2020, at 12:08 PM, Joseph Touch <touch@strayalpha.com> wrote:
>>>>
>>>> Overall, I’d feel a lot better about upending transport checksums if we had evidence that the checksum wasn’t catching errors. If the checksum is correct because it’s being constantly recomputed without being checked, a new alg won’t fix the issue.
>>> Or, use a keyed cryptographic checksum and do not give the key to middleboxes.
>>>
>> I've always had an unease about transport layer security vs transport IPsec. At least I now have something to hang my hat on.
>>
>> Mike
>>
>>