How far can you go before a broadband connection lags? I was in the process of creating a design document when I realize this may not be possible online. The game is a 1st and 3rd person shooter, with Melee and Ranged weapons. (There's a lot more so don't just criticize the idea.) One of the main gametypes I hoped to include was an Aeon of Strife (AoS) type map, where you are a hero on a side and a computer sends soldiers to the other side and your just a general of both the warring sides. The Melee weapons are very... well, interactive, one of my favorites is the whip which can latch on to an enemy unit and throw him away or up against something. (Just an example of how much melee fighting is detailed) I'm not planning on Doom or Half-life graphics, but at a decent graphical standpoint, say, Unreal 2004 graphics. With these graphics, and many onscreen units, could a server handle this? I realize it would take a very fast computer, but I'm much more worried about the multiplayer. If the server could run this, about how many players do you think could play without a severe lag? Thanks

How long is a piece of string? Unfortunately the answer to your question depends both on your definition of broadband and how much data you need to send. And the data you need to send will vary depending on how much of your information is client-side, how effectively you can predict positions and velocities of moving objects, how efficiently you can represent all the possible event types you may need to send, and so on.

You will certainly need to reach a more accurate figure than 'many' for the quantity of units acting at any given time, and think about how much information is going to need to be sent for each, and how often.

Well, I'll get an estimate on the 'many' units. I'll guess about 24 unit spawn per side, plus those that don't die by the time the next spawn enables, So we'll look at about 50 units per side, plus the defending units. I'd say about 125 at the most plus the players.

And the information, just average effeciency, with a decent broadband/dsl connection. I'm not looking for an exact Latency count or anything here. The question is, is just that is it possible without a latency problem?

To be technical, the amount of data you need to send doesn't affect latency, which is effectively constant. The amount of data affects update rate.

125 is not a large number. But you still have to know what is being sent back and forth to make an accurate judgement. Here in the UK a typical broadband connection might be 512kbps, so that's about 50K/s, once you subtract overhead and so on. Let's round up your 125 to 150 to make the calculations easier... that means 3 units per 1K of data. 330 bytes for each unit per second. Personally I think you could get away with a lot less than that, so you'll probably be fine. But to give you a proper answer you will need to give some thought into the technical side of what needs to be transferred in order to keep the game synchronised.