WDS vs. Extend a wireless network

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Level 2

164 points

WDS vs. Extend a wireless network

Can someone tell me the difference between the two options? Thanks.

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Posted on Jan 23, 2011 8:49 AM

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Answer 1

Best reply

Bob Timmons

Community+ 2024

Level 10

159,182 points

Jan 23, 2011 9:06 AM in response to RMS

Welcome to the discussions, RMS!

Can someone tell me the difference between the two options?

One is very good, the other very poor.

"Extend a wireless network allows faster "n" speeds on a network with minimal bandwidth loss. It's easy to configure as well.

WDS operates on "g" wireless only, so even if you have a new Apple "n" router, you'll lose any advantage of having "n" capability on your router.

Each "remote" that you add to a WDS setup will cut the bandwidth on the entire network in half. So, if you have a main base station and remote setup in a WDS confguration, you'll have a "g" wireless network running at 1/2 speed. If you add another remote, the entire network will run at 1/4 speed.

If all of your devices are newer Apple AirPort "n" devices, you can use the "extend" setup.

If any of your devices are not "n" devices, you must use the WDS setup.

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Answer 2

RMS Author

Level 2

164 points

Jan 23, 2011 11:11 AM in response to Bob Timmons

Wow!!! Thanks for the response, Bob. It seems that the "extend" setup is the way to go. Actually, why would you even consider the "WDS" setup if the performance is that bad.

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Answer 3

Jan 23, 2011 12:08 PM in response to RMS

Actually, why would you even consider the "WDS" setup if the performance is that bad.

WDS is your only choice if you have any older "g" routers on your network since they do not have the capability to "extend". 4 years ago, WDS was the only way that you could expand your wireless coverage using wireless only.

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Answer 4

Tesserax

Level 10

148,399 points

Jan 23, 2011 12:39 PM in response to RMS

In addition to Bob's comment, there are actually two "flavors" of WDS: 1) Static, and 2) Dynamic

The 802.11g AirPorts only support the earlier static version which is typically referred to as simply: WDS. On the other hand the newer 802.11n AirPorts introduced the dynamic version ... but they also still support the static one when working with mixed mode AirPorts. The dynamic version is not called out, but is referred to as "extending a wireless network."

As you can see both perform the same basic role: Eliminate the requirement for wires between routers to extend their wireless range.

Three key differences between these two types of WDS:

1. The static version can only operate in the 802.11g mode. Thus it is limited to a maximum bandwidth of 54 Mbps. If you create a static WDS between an 802.11g & 802.11n AirPort, it too will only operate in the 802.11g mode ... so you basically lose the bandwidth advantage of "n".

2. The static version can have three types of base station configurations: main, relay, and remote. This works well if you need to cover a long linear distance, like a rectangular-shaped building, where the Internet comes in on one of the short sides and you want it available on the extreme other end of the building. The dynamic version only supports two types: main & remote. This work best in a situation where the building is squarish and the Internet comes in at the middle and you want wireless coverage to extend to all four corners.

3. As Bob has mentioned, the static version has a hefty bandwidth penalty. For each base station added to the WDS, the overall bandwidth is cut in half ... so just having a main and single remote, that 54 Mbps is now around 27 MBps. While the dynamic version does suffer a bit of the same, it is no where as severe as the static version ... plus you are starting out with the much higher bandwidth that comes with 802.11n.

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Answer 5

hc00jw

Level 1

0 points

Feb 27, 2011 9:05 AM in response to RMS

An extension of this question, if I have two 802.11n airport devices with "Extend a wireless network" option, what speed will it run the 802.11g portion of the network at? Will this still be the reduced 27 MBps, or will this allow it to run at the full 54 MBps?

I mainly ask because right now, I have a 802.11n time capsule extended by a 802.11g Airport Express, which is fine, because most of the devices connected on the extended range are only 802.11g anyway (Wii, PS3, and an old Mac), but I'm wondering whether purchasing a new 802.11n Airport Express would double the bandwidth for these devices (we have 50Mb broadband plugged into the time capsule, not to mention throwing movies from the old Mac to the Apple TV), or whether I wouldn't see any advantages to this new device?

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Answer 6

Feb 27, 2011 11:02 AM in response to hc00jw

The things to remember are these:

1) Whenever you have a "mix" of "n" and "g" devices, you must use the static WDS method to provide more coverage. WDS is limited to "g" speeds, of 54 Mbps, but each "relay" or "remote" on the WDS cuts that bandwidth in half. With 1 remote, you are down to 27 Mpbs, with 2 remotes, down to about 14 Mbps, etc.

2) If all devices are "n" capable, you can use the "extend a wireless network setup. "n" speeds are maintained on the network with much less bandwidth loss per device, about 15% on average. So, an "extend" setup will normally run at about 100-110 Mbps using 2.4 GHz or in the 250 Mbps range if you are using 5 GHz.

If you plan to copy files over wireless, stream video, etc., it's pretty obvious that one setup will work well and other may barely function for your needs.

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Answer 7

Jun 1, 2011 11:33 AM in response to RMS

I have a further question that may have been answered in Tesserax's response. I'd just like further clarification.

If I am using all 802.11n devices on my network and using "Extend" mode, can I "daisy chain" Airport expresses back to the main Airport Extreme while allowing clients to connect to all devices along the daisy chain?

The reason I ask is because I seem to be failing to configure my network in this manner. When going through the Airport setup, when asked at the very end of the process which device I would like to connect to, if I choose another Airport Express that is extending the network, the process fails. Only if I choose the primary Airport Extreme, will the new Airport Express connect to/extend the network successfully.

Any insight is appreciated. Thanks.

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Answer 8

Jun 1, 2011 12:34 PM in response to TheInnerSun

If I am using all 802.11n devices on my network and using "Extend" mode, can I "daisy chain" Airport expresses back to the main Airport Extreme while allowing clients to connect to all devices along the daisy chain?

The "extend a wireless network" feature works like the the hub and spokes of a wheel. The main base station is the "hub" and each "remote" resides at the end of a "spoke". The "remotes" communicate directly to the "hub", not to another "remote" at the end of another "spoke".

So, it is not possible to setup a "daisy chain" type of setup with the "n" AirPort devices.

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Answer 9

ngejay

Level 1

0 points

Oct 13, 2011 2:33 PM in response to Bob Timmons

Is there literally no way to "Daisy Chain" multiple APX base stations using the wireless N settings? I would have thought that as a much newer technology they would have found a solution to making existing technology better. They did make running from the main base station to the remote base station a lot better, but they did away with the relays all together.... I just invested in 4 Airport Extremes, and 2 Airport expresses with the hopes of being able to set it up this way....

I am quite disapointed

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Answer 10

Oct 13, 2011 3:15 PM in response to ngejay

Is there literally no way to "Daisy Chain" multiple APX base stations using the wireless N settings?

Sorry, but no way with "n" settings using wireless only.

The old WDS setup would allow a "relay" type device, but WDS is a "g" technology affair with a massive 50% bandwidth loss for every relay or remote on the network. After a single relay and a single remote on the WDS setup, the network is running at only 25% of normal "g" speeds. Cut that in half again for another remote or relay

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Answer 11

Dec 5, 2011 4:58 PM in response to Bob Timmons

I too am trying to set up a daisy chain of two airport expesses extending the range of a time capsule in a long rectangular house. The time capsule and airport express are the latest versions. I configured the expresses using 'extend an existing network' but as previously discussed the utility hung if I tried to connect one express to the other and I could only complete the setup if both expresses were connected to and therefore in range of the time capsule / base station. This doesn't achieve the range I need.

If I accept the reduced performance of g over n, how do I set up an old style WDS set-up, I can see no way of doing this in the utility or manual setup options.

Thanks in advance.

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Answer 12

Dec 5, 2011 5:45 PM in response to Jared Andrews

My opinion would be that Apple does not want you to use the WDS settings for a number of reasons....some of which have already been mentioned.....so they hide the setup in AirPort Utility.

I am not recommending that you try this unless you are very patient...and don't mind a 75% performance drop on your network.

This is a difficult and frustrating configuration for most users. It's easy to make a mistake and hard to recover without starting all over again...and again.

Please look over Apple's instructions for this before you decide if you want to try this:

http://support.apple.com/kb/HT4262

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Answer 13

Dec 5, 2011 10:41 PM in response to Bob Timmons

Thank you very much, I will give it a go this evening. One final qn though. I don't see in the utility the option to join a WDS network etc, just the 'extend' options. How do I access these?

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Answer 14

Dec 6, 2011 5:51 AM in response to Jared Andrews

As I mentioned previously, Apple hides the setting.

Hold down the option key on your Mac while you click on the Wireless Mode selection box to see more "options" appear.

Let us know how things go with WDS. There are some other possible options to consider...all much faster..... if WDS does not work out.

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Answer 15

Dec 6, 2011 8:32 AM in response to Bob Timmons

Sorry, I missed that. Thank you. Instructions seem straight forward enough.

I get that I need to reconfigure the Airport relay and remote bases to WDS. What I'm unclear about is whether the main base station (TC connected to the internet) has to be switched from 'extend' to 'WDS' also. From the router's perspective shouldn't the relay station and any client of it or the remote station just look like wireless clients whether in WDS static or Dynamic.

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