Slow file transfer speed via Skype?

Question

Skype

Hello.
It so happened that in our company Skype is the standard for communication and file transfer. Nothing to change, the alternatives are not convenient.
There are problems with the speed of transferring files from one end of the country to the other. Well, let's say St. Petersburg <-> Novosibirsk. In two offices, the speed is 100 Mbps, white IP, NAT.
Skype does not work well through NAT, and in general, few people know exactly how it works. Advised to forward a port inside the network for incoming connections. The port itself is registered in the Skype settings. Does not help. Nobody expects that the speed will be 12 Mb / s, but the speed is 2 Kb / s.
Skype severely cuts the file transfer speed when making a call. Yes it is, we tried it. But no one calls, only the file is thrown.
Of course, the channel to Novosibirsk is a problem. But we tried to throw files via scp, for example. Normal speed, 1-2 Mb/s the file is transferred.
Provider cuts p2p traffic? Torrents work fine. Skype works well with Moscow. So I do not think that the provider selectively cuts something.
Has anyone else encountered such a problem? Can you help with advice, what else to try, where to dig?

Answer 1

I would still insist on skype alternatives. Dropbox or Google Drive for example. And it turns out that you use a shovel to cut down a tree, and even complain that it is inconvenient.

Answer 2

Try to really isolate the NAT problem Try
to transfer files between two whitelisted routable addresses

Answer 3

I also have Skype "harmful". 2 kb / s even with moscow> moscow.
So use some kind of dropbox. He fumbles much faster