Hello,

I am looking to build a WDS network. I want to have all of the back-hauls over copper, so no mesh, just wireless distribution with 2.4gHz radios.

If this is all set up properly, how much wireless client active roaming will be able to be done? How long does it take the user to switch to the next AP?

Thanks for the help!

Dan

I wouldn't use WDS, I'd alternate channels, keep the same SSID and security.

If you do it right roaming can be seamless. It generally requires a static IP on the client. Roaming control is based on the client, so the speed of transfer varies wildly.

I've done it at my home walking, two AP's connected by ethernet, static IP, same wireless config on each AP. While playing an MP3 hosted on a desktop using Winamp without so much as a skip.

Why would you not use WDS?

Static IP's are not an option. I would think that the MP3 that you were playing was probably buffered into Winamp.

Thanks for the help!

Dan

From what I understand WDS is a way to handle MAC addresses to allow non ip based traffic to be bridged over a wireless link. It basically allows a wireless link to be a true network bridge like a switch is. It is commonly used to extend the range of a wireless network with wireless back-hauls. Since you are using copper back-hauls I don't see how WDS will help you.

I would deploy the same way as Oldman suggested with different channels and same SSID and security. I believe he is also correct saying that roaming is client and not AP dependent. I have successfully roamed with a dynamically assigned IP.

CPEng

I play with this frequently, DHCP breaks roaming. It takes about a half to one second to change from one AP to another when walking. It generally takes 1-2 seconds for the DHCP handshake and the address to be assigned.

Winamp, at least the version I was using at the time, buffers for about 1 second. I tested that as well.

If you use WDS bridging on the AP's while they are connected by copper you will only create a multitude of network loops. WDS bridging will not help you at all for roaming. The client is looking at far more information than the SSID, security and channel. WDS is useless in this situation.

Roaming is client controlled. If you are in control of the clients you can make it seemless enough to watch a video or MP3 playing over the network without a hiccup. If you don't have control over the client then you actually have very little control over roaming. The best option you have left is access lists, set the signal strength range to disconnect before the signal gets too weak and hope build your network so that once their signal drops they have no choice but to jump to another AP.

edit: MT clients will jump from sector to sector without interrupting stream. Windows and smartphone clients will not. They check DHCP every time they change wireless associations.