[dvdkhlng]

Yes, I had the same confusion. There seems to be a standard for TCP over UDP [1]. But in general, I would assume that it does not help at all WRT any of the packet loss/latency problems posed by satellite links.

TCP is designed for encapsulation in IP, this is why it is called TCP/IP. And UDP is very similar to IP, only difference is that UDP gives you source and destination port numbers and a payload checksum, where IP only gives you a protocol numbers and non-checksummed data. None of these "features" is going to have any effect on how TCP is delivered.

So the only effect that use of TCP over UDP would have here is:

- increase the overhead used for headers, thereby decreasing the MSS (segment size)

- "cloak" the TCP traffic as UDP and thereby prevent any routers and/or middleboxes [2] from applying special treatment to TCP (i.e. traffic shaping, buffering etc.)

Maybe the latter effect is what made a difference for the link in question.

[1] https://tools.ietf.org/id/draft-baset-tsvwg-tcp-over-udp-01....

[2] https://en.wikipedia.org/wiki/Middlebox

edit: formatting