Verizon slows down cache.nixos.org

Hi,

Traffic from cache.nixos.org is slowed down by verizon traffic scanner.
Some connections even break.
Files are downloaded by HTTPs, so the scanner must sniff through privacy layer somehow!
App installation or dependency update time quadruples.
The online support form returns with 404 after submit, lol.

warning: error: unable to download
'https://cache.nixos.org/nar/0brklf2kivha3v86gwyq5cbfws1zbplbscwl5imghp46765pab53.nar.xz':
HTTP error 200 (curl error: Stream error in the HTTP/2 framing layer);
retrying from offset 36257657 in 309 ms

The hostname is usually easy to see in SNI. But it’s e.g. also possible that they work on IP address level, simply throttling all of Fastly or something.

As someone who’s downloaded terabytes from the cache via verizon in the past without any issues, how do you know it’s the ISP intentionally throttling?

Seesaw traffic pattern - speed goes to 0 before at new HTTP request - it means scanner intercepts the request to download and scan the content before delivering in to me.

I was working in a bank like companies and experienced similar issues.
Another marker in Range HTTP header. Once I was downloading files from HTTP server which did support Range header by ignoring it. I injected Range header with values closer to the end of file and the miracle happened - TCP connection became reliable and download speed increased by 20x.
I run Ubuntu and never used any antivirus on my laptop.

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