Advice Needed: How to configure 6 WAPs in a Wireless Network

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Saajid

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Hi.

We've just installed an extensive (CAT5e + Fibre + Wireless) network for one of our clients. The wireless part consists of 6 of these guys: EnGenius M36 Mesh Ceiling AP, MSSID, WDS, VLAN Tagging, PoE, 1 LAN

They are already set up and working, connected directly to the wired network via ethernet, and powered via POE. They are connected an AP mode, but I'm pretty sure there is more we should do to get a better wireless network.

The network (Wired + Wireless) currently supports about 40 PCs, laptops and servers, as well as a number of Smartphones that connect to the wireless network. Ideally, we would like a setup that is secure, but whose security protocols (WPA, WPA2, etc) support the widest number of devices, at the highest possible speed. We have already ruled out use of WEP (for obvious reasons).

Some questions:
  1. How should we set up the channels on each WAP? The 6 WAPs cover most of the working area at our clients premises. Should we setup each WAP on a seperate channel, and if so, how do we determine which channel to use for each WAP?
  2. The WAPs are not setup in mesh mode, but in AP mode. What is mesh mode? Do I need it? Is it a good idea to set it up? Each WAP is fed by a Cat5/ethernet lead.
  3. How do I make it possible for laptops & smartphones to roam throughout the premises without losing connection (assuming they are in an areas covered by one of the WAPs), i.e. the connection gets handed over from 1 WAP to another seamlessly (this is especially important for VoIP calls).
  4. What software tools do you use to help diagnose problems on a wireless network? Are there any good free ones available?

Any help, advice/criticism will be appreaciated.

Thanks.
 
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TheGuy

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Ok I'll take a stab at it:

1. I know some wireless devices have testers which can tell you how busy the channel is, otherwise I just put it on channel 9 as most people leave it on channel 1 so from 6 up it's usually empty. All WAP should be on the same channel with the same SSID if you want seamless hand over from one AP to the next.

2. Mesh is really the option that you want in your scenario so I would read up on how their's work and see if it fits your setup.
 
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Silver-0-surfer

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You should not have all the AP's on the same channel. Even though there are around 11 channels availible most of them overlap with each other. If you are working in the 2.4ghz spectrum then there are only 3 channels availible to you that don't overlap 1, 6, 11

Basically what you want to do is have a map of the area and a general idea of how much area is covered by each AP and then assign the channels to avoid overlap.

# How do I make it possible for laptops & smartphones to roam throughout the premises without losing connection (assuming they are in an areas covered by one of the WAPs), i.e. the connection gets handed over from 1 WAP to another seamlessly (this is especially important for VoIP calls).

I could be wrong but I don't think you will get seamless roaming with those AP's you need a controller based solution i.e. no fat AP's. what TheGuy said might work but not if you have encrytion enabled, and even if its and open network i'm not sure that would work any way. it sounds like if you are trying to do voip calls your going to suffer.

# What software tools do you use to help diagnose problems on a wireless network? Are there any good free ones available?

Depends on the problem, wifi is basically just an extension of you wired network. If you're talking about bandwidth test you can use iperf (free but you must set it up) however if your talking about drop packets etc in the air you really need a spectrum analyzer (and thats $$$)

# The WAPs are not setup in mesh mode, but in AP mode. What is mesh mode? Do I need it? Is it a good idea to set it up? Each WAP is fed by a Cat5/ethernet lead.

Mesh is when you link AP's to one another via wireless, if you have cables don't even bother as you get 50% loss on single radio APs when doing mesh
 
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TheGuy

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@Silver

This is quoted straight from the website:

The MESH faciltiy allows you to create a truly roaming environment the easiest way possible.
Click to expand...


I've done quite a few wireless network setups and the only way to make roaming possible is to make the ESSID, Channel and Security exactly the same.
 
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Silver-0-surfer

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I hear what your saying. I have never worked with AP's like this, all of the wifi installation we do are controller based so there is little to no configuration done on the AP's all users sessions are tracked on the controller which is the best way to guarantee roaming.

If you do it your way and have every ap on the same channel, same ssid and same security then you are causing more trouble than I think you are getting.

Think about it, when you are doing roaming you need a good wifi overlap between access points right, how ever you are putting them on the same channel. so you are pretty much guaranteeing interference on you network.

Also when doing mesh installation each access point is configured to connect to another, correct? because the access point as 1 radio it can only transmit or receive thats a HUGE problem you are definitely going to see some bad performance with a mesh. The only time you should use mesh IMO is using access point with multiple radios so you can have a dedicated radio for the mesh and for serving stations and you cannot run cables. in any case what happens if a mesh ap goes down? any ap connecting to that one would have lost connection to the rest of the network.
 
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Saajid

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Thanks guys for your replies.

TheGuy said:
All WAP should be on the same channel with the same SSID if you want seamless hand over from one AP to the next.
Click to expand...

You sure on the same channel? AFAIK and have read, if you put 2 APs on the same channel within range of each other (i.e. overlapping cells), they will interfere with each other, and reduce the overall bandwidth available in each cell.

TheGuy said:
Mesh is really the option that you want in your scenario so I would read up on how their's work and see if it fits your setup.
Click to expand...

AFAIK and have read, mesh mode is used for routing packets efficiently, over wireless between multiple WAPs. I will investigate further though, perhaps this might be the solution.

Silver-0-surfer said:
You should not have all the AP's on the same channel. Even though there are around 11 channels availible most of them overlap with each other. If you are working in the 2.4ghz spectrum then there are only 3 channels availible to you that don't overlap 1, 6, 11
Click to expand...

This confirms what I've read online on several different websites.

Looks like I'm gonna have to do a whole lote more research to figure this thing out.
 
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