How to forward tcp connection through reverse proxy and store tcp session?

Question

linux

There is such a scheme.

As can be seen from the scheme, the problem lies in the large delay over the satellite channel. If with client requests via http \ http's and data caching, I found enough material to study and write a proxy server, then I found very little for tcp connections, I'm interested in the question of how to forward a tcp or udp connection initially without knowing where the client will contact ? my suggestion is to use the gopacket package to grab the address and port protocol where to send the connection, as well as how to store these same sessions when reconnecting, I roughly understand that a cache is needed, but what exactly should be stored in it? tell me what to read and where to go.

Answer 1

how to forward tcp or udp connection initially without knowing where the client will contact?

For tcp - no way. A TCP connection is characterized by a quadruple (src_ip, src_port, dst_ip, dst_port). Without knowing where the client will contact, you can’t get a four, which means you can’t send it.
UDP is generally a connectionless protocol. Each message (datagram) is forwarded independently of the previous/following ones.
The cache stores frequently accessed data.
Set a big keepalive and socket timeout.
In general, I did not understand what the problem described in the question is. If you are writing a reverse proxy, read about how the *upstream directives work in nginx - maybe the mess will decrease.