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Re:My ISP Is Killing My Idle SSH Sessions by 1vuio0pswjnm7 on Tuesday January 12, 2021 @12:22AM (#25742649)
"Using Maps would load many tiles images, which could overwhelm NAT of CGNAT."

Just curious, were these image resources all hosted on the same domain?

Re:My ISP Is Killing My Idle SSH Sessions by alphager on Tuesday January 12, 2021 @04:00AM (#25744127)
No, and that's by design, as many browsers limit you to two http-connections per domain. When you're loading tens of images (like map tiles), you want to use as many different subdomains as possible to load them in parallel.
Re:My ISP Is Killing My Idle SSH Sessions by mfontani on Tuesday January 12, 2021 @05:00AM (#25744633)
With HTTP/2 one is way better off using one connection to one domain instead.

How has the world changed.

Re:My ISP Is Killing My Idle SSH Sessions by 1vuio0pswjnm7 on Tuesday January 12, 2021 @02:03PM (#25751714)
For many years before "HTTP/2", I have been using HTTP/1.1 pipelining, outside the browser, to download hundreds of files over a single TCP connection.
Re:My ISP Is Killing My Idle SSH Sessions by codebje on Tuesday January 12, 2021 @12:58AM (#25742893)
I'm afraid I don't recall. I suspect that they could not have been, based on best practices for performance at the time and the fact that the problem existed at all. I did, however, find a reference to the problem:

https://meetings.apnic.net/32/pdf/Miyakawa-APNIC-KEYNOTE-IPv...

Slides 12-15 show the degradation of Maps in action. 20 connections per user is a heavily over-committed CGNAT, but that level of port sharing does happen.

Re:My ISP Is Killing My Idle SSH Sessions by Dylan16807 on Tuesday January 12, 2021 @01:37AM (#25743199)
But the "connections per user" limit is per-webserver. You'd have to have thousands of users simultaneously loading maps off the same google server just to run out of ports on one IP.

I bet you could put 10k people behind each IP and never even get close to an issue of this type.

Re:My ISP Is Killing My Idle SSH Sessions by codebje on Tuesday January 12, 2021 @05:56AM (#25745151)
Carrier grade NAT puts thousands of users behind the same IP address - that's what it's for.

You can't put 10k people behind each IP and not have problems. That's 6.5 ports per person, you need one for each connection. Pretty much any website will have issues with that little connectivity.

Re:My ISP Is Killing My Idle SSH Sessions by Dylan16807 on Tuesday January 12, 2021 @10:47AM (#25748396)
> Carrier grade NAT puts thousands of users behind the same IP address - that's what it's for.

It doesn't have to. 100:1 would work just fine. With IPs being about $25 each that's an acquisition cost of less than a dollar per user.

> That's 6.5 ports per person, you need one for each connection.

That's not how connections work. Each user could make a million connections as long as they're spread around different servers. The 65k limit applies to simultaneous connections to a single webserver. Only the most-connected server matters, so probably something at google/youtube/facebook, and even then most of those servers have multiple IPs.