This is a very, very odd problem I'm trying to solve for my husband. He's basically blocked from his work email due to some problem with the web interface. Some https connections don't succeed. Well, it does sometimes succeed, but most of the time they hang. Communications with all other sites is working just fine.
Here's an example URL that's causing problems for me: https://www.otc.edu/CSS/announcement.css
This problem is seen on any device on my home network (Mac (Yosemite), Windows (10), Oracle Linux (6.6), iPhone (8.4)), but only on my home network (residential FiOS 50/50). If I switch to using a different wi-fi network away from home or a cellular connection, I have no problems retrieving the file at all. Further, I've had some friends around the country try to get the file and they report no problems whatsoever. It's somehow specific to my network.
To that end, I thought perhaps it was the Apple Airport Extreme I was using as my main router, so I replaced it with the supplied Actiontec (rev. I) router. (The Airport Extreme is now unplugged.) The problem continues to persist.
I've tried bypassing the backbone switch I've got, connecting directly to the Actiontec. The problem is still there.
Unless I'm missing something, the only thing I can think that's left in common is my FiOS connection, but this doesn't make any sense. Why would it only affect one site?
More techie details...
I installed Wireshark to look at the packets on my Mac. This screenshot shows the sequence of packets that my Mac sees.
[att=1]
Note packet #22. My system is claiming Ack=4801 (which is packet #18), and that SLE=4931/SRE=4968 (which is packet #20). For some reason, it's not acknowledging receipt of packet #19.
Then, as you can see, the remote system continues to send Seq=4801 Len=130 (the missing packet), but my system doesn't acknowledge it.
The strangest thing is that it's not just my Mac. All the devices on my network have the same problem.
Is it somehow possible that FiOS is occasionally munging the data that's preventing my devices from receiving all the packets properly?
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