What algorithms exist for streaming network data processing?

Question

Computer networks

I implemented an application for processing packet headers, the meaning is as follows: data from the gray network enters one eth0 interface, changes and leaves eth1, responses arrive on eth1 and are collected again for the gray network. The application was tested and profiled, the bottlenecks were closed. The Golang programming language used its power in the form of channels and goroutines. Now I was able to squeeze out a speed of 35 Mb / s, the maximum channel width is 50 Mb / s.

Answer 1

But why? Why did you invent NAT?
And what is your question?