WDS query: WLAN throughput halved?

Hi,

I have a WDS setup with v1 and v2 WRT54G routers, both running DD-WRT v23
(25/12/05).

Router 1 is the gateway to my BB connection, and router2 is the
repeater/node.

Looking at router2's config pages, specifically Status tab > Wireless tab,
the Wireless rate is listed as 24Mbps, while on router1, this is listed as
48Mbps.

Does the halving of the WLAN throughput apply only to the WDS node? Or am I
misunderstanding what these rates are?

Many thanks.

On 2/9/2006 12:27 PM, __spc__ wrote:
> Hi,
>
> I have a WDS setup with v1 and v2 WRT54G routers, both running DD-WRT v23
> (25/12/05).
>
> Router 1 is the gateway to my BB connection, and router2 is the
> repeater/node.
>
> Looking at router2's config pages, specifically Status tab > Wireless tab,
> the Wireless rate is listed as 24Mbps, while on router1, this is listed as
> 48Mbps.
>
> Does the halving of the WLAN throughput apply only to the WDS node? Or am I
> misunderstanding what these rates are?
>
> Many thanks.
>
>

Each WDS node will cut your speed in half as it has to receive and
forward at the same time.

"__spc__" <s p a m t i m e @ n t l w o r l d . c o m> hath wroth:

>I have a WDS setup with v1 and v2 WRT54G routers, both running DD-WRT v23
>(25/12/05).
>
>Router 1 is the gateway to my BB connection, and router2 is the
>repeater/node.
>
>Looking at router2's config pages, specifically Status tab > Wireless tab,
>the Wireless rate is listed as 24Mbps, while on router1, this is listed as
>48Mbps.

Those are the wireless connection rates. That's the over the air
speed of the two wireless connections. It can be any rate from
1Mbit/sec to 54Mbits/sec.

Ignoring WDS for a moment, your actual thruput will be about half of
the connection rate.

>Does the halving of the WLAN throughput apply only to the WDS node? Or am I
>misunderstanding what these rates are?

It's a coincidence that one rate is exactly half the other. Move the
antennas around or insert an obstruction and watch the connection
rates change.

Where WDS cuts the thruput in half (again) is because only one
transmitter can be on the air at a time. One half the link will need
to wait until the other half is done transmitting. This cuts the over
the air thruput in half. So, with your 48 and 24Mbit/sec connection
speeds, you'll get a thruput of 12Mbits/sec with WDS.

--
Jeff Liebermann (E-Mail Removed)
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

"Jeff Liebermann" <(E-Mail Removed)> wrote in message
[snip]
> Where WDS cuts the thruput in half (again) is because only one
> transmitter can be on the air at a time. One half the link will need
> to wait until the other half is done transmitting. This cuts the over
> the air thruput in half. So, with your 48 and 24Mbit/sec connection
> speeds, you'll get a thruput of 12Mbits/sec with WDS.
>
> --
> Jeff Liebermann (E-Mail Removed)
> 150 Felker St #D http://www.LearnByDestroying.com
> Santa Cruz CA 95060 http://802.11junk.com
> Skype: JeffLiebermann AE6KS 831-336-2558

Thanks for that - learning more and more about this every day!