Protocol Bible - talk about ports and quads

First, let's talk about libraries and open source software

Some libraries made by server software , Many libraries have the following problems ：

1、 Insist on using quads to make a conversation session

It's like the old one rtp lib library jrtplib Is to use such tuples to identify session Of ,udp Incoming and tcp Incoming different , Suppose you use a proxy , In addition to the two-tier agreement agent , If you use a four layer proxy , You get the source port and source IP It's the same , This will cause an error , Even rtp In the agreement ssrc Dissimilarity , He also caches it as a ssrc, Use getssrc An error occurred in the function , This is his bug

2、 Don't recognize ssrc

This is the same as the above problem , But it's not a , distinguish ssrc Is the normal practice of multiple channels in a tuple , Of course you can payload To identify different sources , Such as audio and video , But it's not enough . such as zlMediaServer, It is also unrecognized , Find data of the same tuple ,ssrc Different from before , Direct discarding , It's not right .

3、 practice

Quadruple should not be regarded as copper strip , Should put the ssrc and payload separate from , For example, when acting as an agent .

tcp The agent has no problem ,session The conversation has changed , The port has changed .

udp agent , If you use the same IP, Same port , Many software have errors .
Here's what I did udp Use different ports in the transport layer , Just distinguish the different IP source , Assign different ports to it , Like those server It still works .

4 summary

Just a few words , If we can understand , It shows that we are a doer , I understand these theories in practice . Later, add code to explain .