Which data to transfer?

[FaVorith]

Hi!

Is there any information about techniques to use in order to keep traffic and latency low? I'm wondering which data a huge MMORPG sends and receives while still running without lags... . I fear to get huge problems with my own project when trying to work with absolute positions which had to be sent as often as possible... .

Sincerely yours,
FaVorith

[zammbi]

I wouldn't mind also knowing the best way for the client to know its position (3d) with the less amount of packets.
What I thought up: the server would send speed, direction and acceleration if needed, then send another packet if its changed or the player stops moving.
So the client would would out all the between. The client could also auto work out the gravity part so the server wouldn't need to send that info.

[cylab]

I also think MMORPG use spatial division to just update relevant areas.

Games published by our own members! Check 'em out!

[lhkbob]

At least with WoW, they aren't able to keep things concurrent across all systems.  I've played with a friend next to me and we've seen different scenarios (sometimes  gameplay affecting) if the internet is slow.  cylab is right that they only need to send each client the relevant info.  I think that they also benefit from the style of gameplay, the exact location isn't needed to make an attack or cast a spell.  A possible solution is to interpolate between positions, or guess by using velocity measurements to fake accurate movement, and then fix the locations as newer packets arrive.  This is a concern in FPS games as well.