We use compression for server-to-client packets in Artifact. We use the zlib compression algorithm and see roughly 40%-60% packet compression.

We delayed trying compression because we figured the overhead of compressing/decompressing would be prohibitive. When we finally gave it a try, though, it was a huge success. Bandwidth used dropped significantly, and the game seemed much more "snappy" than before.

The time required to compress/decompress the data is significantly less than the time saved by sending less information.

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DavidRM
Samu Games
http://www.samugames.com

Hmmm interesting ideas...got a link for that zlib compression algorithm?

From the zlib readme:

The zlib home page is http://www.cdrom.com/pub/infozip/zlib/
The official zlib ftp site is
ftp://ftp.cdrom.com/pub/infozip/zlib/

zlib is used in the Linuz/Unix gzip/gunzip commands. It's fast and compresses reasonably well.

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DavidRM
Samu Games
http://www.samugames.com

As I was pondering the complexities of network latency (and why it always takes so long to download BSP maps in TFC ) the thought occurred to me that some sort of data compression might improve connection speed. Picture this: all the packets you send would be compressed (maybe with pkzip?) and then upon recieving a packet the client would decompress it. Now, i'm guessing that this would create a significant performance hit, but, I don't think it would be an issue on high end systems, like my own. Of course, multiplayer data compression could already be common place and i'm just wasting my time. Just a thought...

-Chlorine

Just for the record, Qizmo, the QW proxy also uses a GZ compression. The in game dosent change much, xept you can pull your rate up (amout of packets in a minute) becose your bandwith IS freed up. U can share a ISDN line with two players easy. It is a prety cool thing, wonder if they'll one day put hardwarecompression in lan card (they alllready are in modems)