Wireless Access Point SSID Question

[mseaney]

I have just set-up 4 wireless Netgear access points in our school building all connected to the same network segment in different parts of the window. When it comes to SSID can you set all access points to the same ID? or do they have to be different?

Thanks
Michael.

[Geoff]

If you set them to the same SSID WinXP SP2 will not roam between the access points correctly. Its a bug. I usually set my AP's up with descriptive but unique names. eg,

SCHOOL-R23
SCHOOL-LIB
SCHOOL-HALL

etc.

That way you can see what AP your connecting to.

[Ric_]

I've never had a problem setting all the SSIDs the same on D-LINK APs. In fact I've found the transition between APs while roaming has been seamless.

Make sure that you don't have them all on the same RF channel though - that will cause interference if they are near enough together.

BTW - an interesting piece in PC Pro this month about turning the omni-directional antennae into directional ones with increased gain by putting a curved piece of foil benind.

[Geoff]

I've never had a problem setting all the SSIDs the same on D-LINK APs. In fact I've found the transition between APs while roaming has been seamless.

Only applies if you using Windows Wifi Zero config whatsit. Regardless, its nice to acutally know which AP your connected too.

Make sure that you don't have them all on the same RF channel though

Unless your using WDS (and you should if your AP's support it) in which case you need all your APs on the same channel.

[StewartKnight]

sorry Geoff, but I have to disagree!
Set them all to the same SSID, especially if their not WEP'd or whatever.

(BTW I don't wep, because the nearest property is far to far away)

The "trick" is to make all the channels 6 away from each other,to avoid cross over etc.

[GrumbleDook]

@stewartknight
unless you use Cisco APs then you can have the channels at 1, 5, 9, 13 to give you a better density of APs without the risk of interefence ...

But if you have modern Cisco APs you just let it use least congested and it manages it for you.

[ajbritton]

Can anyone tell me more about using WDS (wireless distribution system). It sounds like this totally gets aroung the problem of the limited number of channels at 2.4GHz...

[Geoff]

It basically lets the AP's communicate with each other wirelessly. This way they don't interfere with each other as much plus roaming tends to work better. Also you can add new AP's that aren't physically connected to the wired LAN, they will simply re-route traffic wirelessly to the nearest connected AP.

You set it up like this:

1. Your AP's need to preferably be the same make/model.
2. Set all the AP's to the same channel.
3. On each AP you enter the MAC addresses of all the other APs.

[ajbritton]

@geoff: Presumably there is some trade-off with performance if more traffic is routed onto the LAN by fewer APs?

[Geoff]

Yes, remeber that your Wifi bandwidth is shared. The more APs/clients/etc there are that are active the slower everything goes.

[GrumbleDook]

@stewartknight
unless you use Cisco APs then you can have the channels at 1, 5, 9, 13 to give you a better density of APs without the risk of interefence ...

But if you have modern Cisco APs you just let it use least congested and it manages it for you.

For information ... Cisco APs' option to use "least congested" when it comes to channels is *not* the same as WDS ... it seems to be a sort of halfway house.

Most of the WDS systems touted earlier than 12 months ago will usually be reliant on software on a centrally controlling machine, and not what Geoff has described which is based around the APs themselves.

There are changes going on with Cisco and other manufacturers to provide a thin client style solution. The APs pull a configuration and data from a mast AP or machine on the network whilst keeping the AP as clean as possible.

We will get teh Cisco version some time next term (our present APs can be rolled over to this) at it looks like it could be fun.

[Geoff]

Most of the WDS systems touted earlier than 12 months ago will usually be reliant on software on a centrally controlling machine, and not what Geoff has described which is based around the APs themselves.

My experiences are with 54mbit and 108mbit Buffalo APs.

[mseaney]

Thanks for all your help guys. The access points are working fine. Lets hope they hold that way.

Cheers
Michael

[tarquel]

just a slight deviance here...

Saw a WDS capable adsl router for the first time [well - first time i noticed the feature that is lol] in a 3com one and I tried to link it to a wireless AP [linksys one] at a mates house but no luck.

I missed the blinding factor that both AP's need to support WDS then lol

but anyway, my thought was could you use this kind of system to setup a wireless IP CCTV system [cheaply] as would definately be a help in installing an additional cctv system.

Would the performance be good enough on this kind of wireless system?

Cheers
Nath

[E1uSiV3]

You still need to power the cameras tho Tarq, id stick to PoE cameras for performance, reliablity, security and just about any other reason i can think about lol