AT&T Internet 75 (U-Verse) in SF Bay area (Home) to work about 7 hops away, all within AT&T
While DSLreports shows bandwidth at my house as 45Mb/s down and 20Mb/s up, when I try to transfer many (say, 200) megabytes of data in a file (up or down), the transfer program gives up after 1 to 5MB transferred. For the first second, it shows full bandwidth being used, but then quickly drops off and often shows a status of "stalled" and transfer rates of maybe 100Kbps and less (yes, I know the difference between Bps and bps). (It doesn't matter if my network traffic is encapsulated by a IKEv2 VPN.)
These transfers are usually using ssh to/from work (I'm a multi-decade sysadmin & network admin), which is 27ms ping from home (20ms from my router to AT&T!). That's not slow enough for TCP windowing to be a big problem.
I don't try to transfer big files often (every few months), but I've experienced this for more than a year, since I moved to this AT&T service 1.5 years ago. I don't recall any trouble with this on Xfinity, and certainly have no trouble within work.
The only explanation I can think of is that AT&T is using QoS to limit/block bandwidth to ssh & vpn, relative to whatever is tested with the DSLreports Speed Test (https?). It sorta makes sense as people may usually think of ssh and vpn as used interactively (ie, low, bursty, two-way bandwidth).
Do others see (or not see) this problem, and can anyone confirm or deny AT&T is doing this QOS to cause ssh and vpn traffic to go badly?
[Sorry. Originally posted in DSL. Should be in U-Verse]
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