If you're in trouble and cannot find an answer to a question which goes beyond Stack Overflow...
If you have a not-so-usual solution for your problems but need to justify it to your boss...
If you like to think on your own rather than blindly follow "common wisdom" and "profound truth"...
...then 'No Bugs' Hare on Soft.ware might be the right place for you.
Your mileage may vary. Batteries not included

Network programming is one field which everybody uses but very few people really know in depth. Our IT Hare did write a software which processes billions of network packets per day; moreover, they’ve done it in a very robust and efficient manner. And last but not least, they’re ready to share their experience :-)

Network Programming, page 3:

MMOG. Point-to-Point Communications and non-blocking RPCs

Quote: “In other words, you can write your code ‘as if’ all-your-code-within-the-same-FSM executed within the same thread”
Another Quote: “As soon as we have these two parts of processing – we can say that our Server-to-Server communication is tolerant to all kinds of transient inter-server disconnects”
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MMOG: World States and Reducing Traffic

Quote: “In practice, for most classical RPGs you can get away with simulating each of your PCs and NPCs as a box (parallelepiped), or as prism (say, hexagonal or octagonal one)”
Another Quote: “Mathematically speaking, without Interest Management, the amount of data on our servers will need to send (to all players combined), is O(N^2). Interest Management reduces this number to O(N)”
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MMOG. RTT, Input Lag, and How to Mitigate Them

Quote: “For fast-paced games, there is one big problem with the flow shown on this diagram, and the name of the problem is “latency” (a.k.a. ‘input lag’)”
Another Quote: “No, better bandwidth doesn’t necessarily mean better latency”
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Contents of “Development and Deployment of Multiplayer Online Games: from social games to MMOFPS, with stock exchanges in between”

Abstract: There are lots of things to think about when developing a massively multiplayer game
Quote: “Good Development & Deployment cannot make your game, but bad ones can easily kill it”
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If they wrote it in a book, it MUST BE GOOD CODE!
Or
How many mistakes can fit into 100 lines of book tutorial code? Part 2

Abstract: There are books and there are books. Some of the books can be trusted. Some are to be avoided.
Quote: “While the detection of pointer parameter being NULL is almost universally a good idea, having it silently ignored might lead to difficult-to-find bugs.”
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If they wrote it in a book, it MUST BE GOOD CODE!
Or
How many mistakes can fit into 100 lines of book tutorial code. Part 1

Quote: “Throwing away 1400 bytes for no reason for every single network message is an outrageous waste”
Another Quote: “Having this kind of stuff in your code is like having a time bomb: it will explode, and for any sizeable project if will usually happen sooner rather than later (unless, of course, “later” is the worst possible time for the explosion to happen)”
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