Bandwith requirements for event

Hi!

We're planning to hold a corporate event in Second Life for one of our customers. We are looking at approx 40-50 connected users/computers. The question is how much bandwidth we need (per user) to make the experience enjoyable? The conference center has an 8Mbit asymmetric DSL connection, upgradeable to 16Mbit, which would give something like 160/320Kbit per computer.

Are there any official figures, or has anyone in this forum any personal experience to share?

Thank you in advance!

Magnus

The biggest problem would be the point where a few people/everyone start logging on at the same time. If you can get everyone to log on orderly then things should go smoothly.

Once everything is rezzed the available bandwidth should be enough to accomodate everyone (assuming you're not using audio or video streams as well).

If you'll be using voice then things might be very different, and there might also be an issue of packet loss (not sure if SL dropped UDP in favour of TCP yet). Also, SL can not play nice on certain wireless networks but you didn't say whether the puters would be wired or wireless.

If you have access to the puters, it might be a good idea to set them to some more acceptable settings as well (draw distance at 96m or 128m and bandwidth to a reasonable number) or make it a suggestion to keep from saturating the connection.

Thank you for your answers!

We are free to use both wired or wireless networking based on what works best. Logging on orderly will also not be a problem. We do however plan to use voice, but only one way (for a speaker/presenter) the participants will only recieve the audiostream.

Dont think it will be enough.. that stream .. if you want it to have quality is gonna take up quite some of that bandwidth..
BUT if you stream it locally its probably possible.

Ok, maybe a locally hosted TS och Vent on the LAN would be the better option then?

You could have a 100mbs connection and if SL is running slowly, or high packet loss, pings high, timedilation drops, you are all going to lag.

I would suggest that you drop all the eye candy in preferences, set the bandwidth in each client to approximately (requires experimentation) to around 380kbs, reduce draw distance down to 64, composite layers to 2, particles to 0, fog to 1.0, take off all bling, scripted objects, flexi and primed objects, log in in a sequence to a class 5 server, wait until everything rezzes/settles down, tp to your destination in order, again waiting for everything to settle down, then those with the biggest lag, up their network bandwidth in preferences say 20kbs increments, so everyone has a bearable experience. Setting the bandwidth in the client, is not a fixed element, the client will throttle itself around that figure, however it is not very responsive, so don't rush to adjust it eachtime.

I would estimate it isn't going to be so much your download speed thats going to cause issues, more the shared upload speed. 16MB ASDL is download potential (not actual), but upload would be in the region of a maximum of 256-512kbps shared. Eachtime a user moves, and at set increments, each of your clients sends a stream of packets to anyone with your veiw (including adjacent sims). The stream isn't as heavy as the download (as it downloads textures etc), but you still have to consider 40-50 users upload streams divided by 256-512kbps at best. Packet loss and latency maybe too high.