Questions tagged [networking]
Two or more computers connected together via cable bound or wireless communication links for the purpose of information exchange.
896
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How can I simulate a bad internet connection for testing purposes?
I am developing an online multiplayer game. It works well when I test it on the local area network, but before I release it I would like to test how the user-experience works out for someone who has ...
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Is UDP still better than TCP for data-heavy realtime games?
I know that UDP is usually recommended for real-time multiplayer games with high data usage.
Most articles are serval years old, and since ~80% of all data transmitted on the internet is TCP, a lot ...
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How to write a network game? [closed]
Based on Why is it so hard to develop a MMO?:
Networked game development is not trivial; there are large obstacles to overcome in not only latency, but cheat prevention, state management and load ...
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58
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9
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Is the TCP protocol good enough for real-time multiplayer games?
Back in the day, TCP connections over dialup/ISDN/slow broadband resulted in choppy, laggy games because a single dropped packet resulted in a resync. That meant a lot of game developers had to ...
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9
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How are deterministic games possible in the face of floating-point non-determinism?
To make a game like an RTS networked, I've seen a number of answers here suggest to make the game completely deterministic; then you only have to transfer the users' actions to each other, and lag ...
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How can I make a peer-to-peer multiplayer game? [closed]
How can I make a p2p multiplayer game?
I would like to have a server-less multiplayer game. But then, how all the clients know each other?
Why the p2p-protocol is so famous in file transfer but not ...
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4
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How does client-side prediction work?
I've read Valve + Gafferon and hundreds of pages from Google, but for whatever reason I can't get my head around client prediction.
To my understanding, the basic problem is:
Client A sends input at ...
- 861
35
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4
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Movement prediction for non-shooters
I'm working on an isometric 2D game with moderate-scale multiplayer, approximately 20-30 players connected at once to a persistent server. I've had some difficulty getting a good movement prediction ...
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34
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5
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Lag compensation with networked 2D games
I want to make a 2D game that is basically a physics driven sandbox / activity game. There is something I really do not understand though. From research, it seems like updates from the server should ...
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How to network this entity system?
I have designed an entity system for an FPS. It basically works like this:
We have a "world"-object, called GameWorld. This holds an array of GameObject, as well as an array of ComponentManager.
...
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9
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How does delta compression reduce the amount of data sent over the network?
Many games use the technique of delta compression in order to lower the data load sent. I fail to understand how this technique actually lowers the data load?
For example, let's say I want to send a ...
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3
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How to handle a large number of pickups in a MMO game
How do games like Minecraft, or really any MMO game that has pickups, handle them?
Say terrain spawns 3 pickup drops of "dirt" everytime you dig said terrain.
Say every item has a rotation ...
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26
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2
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What's the performance benefit of saving all logged in characters in MMOs in regular intervals?
The majority of MMORPGS have a Worldsave system that will save all the characters once every X hours. I guess the reason is performance. So why is this better, performance wise, than saving a ...
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26
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2
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What to send to server in real time FPS game?
What is the right way to tell the position of our local player to the server? Some documents say that it is better to send the inputs whenever they are produced. And some documents say the client ...
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Techniques to prevent non-official clients in network gaming?
In multi-player network games, what techniques exist to try to ensure that users are connecting with the official client application, and not some hacked client app?
I realise there is probably no ...
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How to keep server-client clocks in-sync for precision networked games like Quake 3?
I'm working on a 2D top-down-shooter and doing my best to copy concepts used in networked games like Quake 3.
I have an authoritative server.
The server sends snapshots to clients.
Snapshots contain ...
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3
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Why do some networked games use interpolation and some use pathfinding for remote movement?
This is a bit of an open question but I'd like to see someone contribute a good reasoning for both.
For a quick example of both:
Interpolation Model
Think the Valve model where the client is ...
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How do/should MMOs handle disconnection during PvP?
In an MMO (not even necessarily an MMORPG) what are some techniques for dealing with players disconnecting in the middle of PvP?
In particular - how do you avoid adversely affecting people who get ...
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Tricks in game mechanics to avoid dealing with network lag compensation?
Implementing network lag compensation is hard, how to avoid it?
Maybe it's possible to use tricks and build game mechanics in such a way that lag would be percieved as a non critical or even as a ...
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How to make a multiplayer game work reliably behind NAT?
Even games that are 100% client/server sometimes have issues when the client is behind NAT. Peee-peer games are even a bigger issues. Some games need to use multiple transports (such as UDP and TCP) ...
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4
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Best strategy (tried and tested) for using Box2D in a real-time multiplayer game? [duplicate]
I am currently tackling real-time multiplayer physics updates for a game engine I am writing. My question is how best to use Box2D for networked physics. If I run the simulation on the server, should ...
Simon Grey
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Are huge, static objects like environment transmitted from server to client in modern multiplayer games?
I have an authoritative system, where when the player joins the match, it gets all the already spawned objects - spawned on itself (the client).
It looks like this:
...
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What is better? Lots of small TCP packets, or one long one? [closed]
I am sending quite a bit of data to and from a server, for a game I'm making.
I currently send location data like this:
...
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9
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Real-time Debugging Techniques
There's nothing quite like the routine of tweaking a variable, compiling code that takes a few minutes, executing the code, realizing that your tweak was in the wrong direction and repeating the ...
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How do I efficiently code both the client and server at the same time?
I'm coding my game using a client-server model. When playing on singleplayer, the game starts a local server, and interacts with it just like a remote server (multiplayer). I have done this to avoid ...
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How can I assign entity IDs in a robust way in a network game?
I'm working on an entity system for a networked game and I'm assigning each entity a unique 32-bit integer id that I can use to serialize references to entities and the entities themselves.
Currently ...
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4
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What is involved for a simple UDP game?
I once tried to write a simple game with UDP in a week as a throwaway test. It went horribly.
I threw it away early. The main problem i had was restoring the game state of all players/enemies/objects ...
16
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5
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Networking for Real Time Strategy games
I'm developing a real time strategy game for a computer science course I'm taking. One of the harder aspects of it seems to be client-server networking and synchronization. I've read up on this topic (...
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Acknowledgement reliability using UDP
I have a question about UDP. For context, I'm working on a real-time action game.
I've read quite a bit about the differences between UDP and TCP and I feel I understand them quite well, but there's ...
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Prevent players from wallhacking in an online FPS?
Why do we still complain about wallhackers in multiplayer first-person shooters?
Isn't it possible to perform occlusion culling for all players server-side? For example, send player xyz information ...
- 1,205
15
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9
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Adding multiplayer to an HTML5 game [closed]
I am interested in making a game that I currently have a co-op experience, however I'm curious as to the best method of implementing this in HTML5.
I have made games before using straight C sockets, ...
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3
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Should I keep login server apart from game server?
I'm thinking of making a MMO server, and I've been looking at how other games structure their network. One of the things I've noticed is that there's always a Login server and then the game server(s).
...
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Should the game host be the authority, or another dumb client?
When designing a networked multiplayer-game where one player hosts and others connect, there are two strategies I'm aware of:
Have the host-player's game be the authority, with all other players as ...
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4
answers
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Does it make sense to use both TCP and UDP at once?
After reading Is UDP still better than TCP for data-heavy realtime games?, I'm wondering if it makes sense to use both TCP and UDP at the same time, but for different things:
TCP for sending ...
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Is there a pattern for writing a turn-based server communicating with n clients over sockets?
I'm working on a generic game server that manages games for an arbitrary number of TCP socket-networked clients playing a game. I have a 'design' hacked together with duct-tape that is working, but ...
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How to compensate for moving objects with client side prediction?
I'm implementing a game server that supports Star Control-like melee. So you have ships flying and shooting, with super simple velocity/acceleration/dampening physics to drive movement.
I've read ...
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What is the difference between a "ping" and "RTT" (round-trip time)?
RTT, or round-trip time, is the time that it takes to send a message and receive the result from server. As I searched this, this seems to be the same as ping in network jargon.
Are there some ...
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multiplayer networking with physics
I'm curious how multiplayer networking with physics is implemented in racing games.
We have a physical world with multiple fast-moving vehicles controlled by different people.
Let's say that vehicles ...
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4
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How to protect your real time online shooter from potential bots
I'm looking to create a multiplayer top down shooter. While I've read about different topics, I can see them I've got some real challenges ahead, but I'm all up for it.
One thing I can't understand ...
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2
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How can I stop the player from drifting due to local input prediction when they stop?
I'm working on a 2D server-client multiplayer game engine (which you can try here). It uses WebRTC DataChannels. (The connections are peer-to-peer, but the host ...
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Prevent Multiplayer Cheating
I am almost complete developing a small indie-style multiplayer game. While I intend to allow people to cheat in single-player, this is obviously not acceptable in multi-player. Does anyone know of ...
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Run a physics simulation on both client and server?
I'm implementing a multiplayer asteroids clone to learn about client/server network architecture in games. I have spent time reading GafferOnGames and Valve's publications on their client/server tech....
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How does the 3G network assign IP to smartphones? [closed]
I am playing a game on the 3G network using Android or Iphone.
Suppose I am moving from one cell to another; Will the IP Address change?
If yes, then how can I continue the same game while changing ...
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3
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Javascript and PHP for real-time multiplayer? [closed]
I'm wondering if combining Javascript clientside with PHP/mysql serverside is a good idea for HTML5 real-time multiplayer (small scale) browser games?
My technical knowledge is very limited, and even ...
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What is involved in creating a real-time multiplayer platformer game?
I'm creating a platformer game that has a "co-operative" feature which I'd like to work over networks / the internet.
Now I've read up on network game programming including articles like What every ...
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Implementing network smoothing
We are making a multipler first person shooter.
The client sends it's position to the server at a fixed rate (currently at 10Hz). The server sends a single message contatining all player's positions ...
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13
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2
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How would a game-state snapshot system be implemented for networked real-time games?
I want to create a simple client-server real-time multiplayer game as a project for my networking class.
I've read a lot about real-time multiplayer network models and I understand the relationships ...
- 1,160
13
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3
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P2P network hiding positions?
I have been working on a P2P architecture for secure gaming and I have divided the problem into five sub-problems:
Unlawful modification of sent game state
Accurately drop cheaters
Agreeing on a game ...
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4
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How do you allow networking code to be written in the later stages of the development?
I'm currently in the early progress of writing a game which I eventually will want to improve in most aspects.
How can I skip out on writing network code yet leaving it fairly easily implemented, that ...
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3
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Limitations of p2p multiplayer games vs client-server [closed]
I am reading up on multiplayer game architecture.
So far most of the articles i've found deal with the client-server model.
I'd like to know what are the limitations for using a p2p architecture? ...
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