nanog mailing list archives
Re: QUIC traffic throttled on AT&T residential
From: Daniel Sterling <sterling.daniel () gmail com>
Date: Wed, 19 Feb 2020 23:31:22 -0500
On Wed, Feb 19, 2020 at 8:27 PM Masataka Ohta <mohta () necom830 hpcl titech ac jp> wrote:
A problem of QUIC with NAT is that existing NAT can not detect graceful shutdown of QUIC and must depends on timeout. So, port numbers may be used up before timeout.
Hmm, this is not what is happening. I managed to (fairly easily!) reproduce the issue earlier tonight. I generated a fair bit of UDP traffic via xbox, a corporate VPN, and youtube over quic. Sure enough, after about 45 minutes, the YouTube app on my iPad paused and then auto-reset the stream quality to "144p" resolution. I was able to set it back to 720p60, but that only lasted about 2 minutes before the stream stopped playing. I waited several minutes for it to resume; it did not. So, I then blocked UDP 443 on my router. The video then *immediately* resumed at 720p60. I didn't run tcpdump but I did grab some screenshots of iftop. It looks like my iPad connected to AS15169 with a single UDP connection. I see one consistent source and dest IP / port combo for those 10s of minutes, up until UDP is blocked. Local port 58053, remote port 443 on the same IP for the whole time. At first the connection averages around 2mbps; when the issue occurs, I see it has dropped to a rate of under 200kbps. I've no idea what to make of that. Surely Google isn't throttling their traffic to me? If so why allow a fallback to TCP? When I originally discovered this issue, I was of course not trying to do anything odd with my internet connection. And I didn't immediately know QUIC was the issue. Only after it happened several times did I dig into the traffic and then block QUIC, and I was shocked to see that both resolve the issue and prevent its recurrence. So again -- I hit this issue repeatedly without trying to -- And just now, I was able to reproduce it simply by generating a bit of UDP traffic on purpose! I only wish I were insane; but from where I'm sitting, QUIC has broken my internet, and the resolution is blocking QUIC. -- Dan
Current thread:
- Re: QUIC traffic throttled on AT&T residential, (continued)
- Re: QUIC traffic throttled on AT&T residential Jay Hennigan (Feb 20)
- RE: QUIC traffic throttled on AT&T residential Hiers, David (Feb 27)
- Re: QUIC traffic throttled on AT&T residential Daniel Sterling (Feb 18)
- Re: QUIC traffic throttled on AT&T residential Mark Andrews (Feb 18)
- Re: QUIC traffic throttled on AT&T residential Damian Menscher via NANOG (Feb 18)
- Re: QUIC traffic throttled on AT&T residential Daniel Sterling (Feb 18)
- Re: QUIC traffic throttled on AT&T residential Töma Gavrichenkov (Feb 18)
- Re: QUIC traffic throttled on AT&T residential Daniel Sterling (Feb 19)
- Re: QUIC traffic throttled on AT&T residential Mark Andrews (Feb 19)
- Re: QUIC traffic throttled on AT&T residential Masataka Ohta (Feb 19)
- Re: QUIC traffic throttled on AT&T residential Daniel Sterling (Feb 19)
- Re: QUIC traffic throttled on AT&T residential Tom Beecher (Feb 20)
- Re: QUIC traffic throttled on AT&T residential Ca By (Feb 20)
- RE: QUIC traffic throttled on AT&T residential Keith Medcalf (Feb 20)
- Re: QUIC traffic throttled on AT&T residential Dave Bell (Feb 20)
- Re: QUIC traffic throttled on AT&T residential Aled Morris via NANOG (Feb 20)
- Re: QUIC traffic throttled on AT&T residential Ca By (Feb 20)
- Re: QUIC traffic throttled on AT&T residential Dave Bell (Feb 20)
- Re: QUIC traffic throttled on AT&T residential Blake Hudson (Feb 20)
- Re: QUIC traffic throttled on AT&T residential Ca By (Feb 20)
- Re: QUIC traffic throttled on AT&T residential Matthew Kaufman (Feb 20)