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A comment on AT&T Fiber in the SF Bay Area is flipping bits. Parent comment

Re:AT&T Fiber in the SF Bay Area is flipping bits by ericbarrett on Tuesday December 08, 2020 @02:00AM (#25342671)
Checksums are also often recomputed on transit if the packet is intercepted, e.g. to limit TTL, unflag odd/unused TCP features, that kind of ISP-ish preening. So if it was a software error or even a hardware problem in the right (wrong) spot it’s possible to get this kind of corruption without retransmits.
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Re:AT&T Fiber in the SF Bay Area is flipping bits by noncoml on Tuesday December 08, 2020 @01:54PM (#25349757)
I think you are confusing the IP header with TCP header.

Routers don’t touch the TCP header at all

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Re:AT&T Fiber in the SF Bay Area is flipping bits by ericbarrett on Tuesday December 08, 2020 @11:56PM (#25355521)
No. URG, “Christmas tree” packets, etc. all can be mangled by the ISP. Or more commonly dropped
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Re:AT&T Fiber in the SF Bay Area is flipping bits by Avery3R on Tuesday December 08, 2020 @09:39PM (#25354674)
if your router does NAT it touches the tcp header
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Re:AT&T Fiber in the SF Bay Area is flipping bits by noncoml on Tuesday December 08, 2020 @10:12PM (#25354902)
You are right, although NAT could be classified as a firewall feature, that runs on routers.

But in any case it's irrelevant in this context as ATT shouldn't be doing any NAT

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