WDS performance and best practices

RouterOS Wireless Networking
1

Hi,

I’m having some troubles with WDS dynamic-mesh performance and I have some questions about best practices.

Here is my setup:
2 x (RB 433 UAH, ROS 4.10, R52Hn)
The wireless interface is in WDS, which is added to a mesh, and it is working as “ap-bridge”.

Now, when I have no WDS enabled, just 1 MT is station and 1 is ap-bridge, performance looks like this:
tcp, both = 46.5Mbps/46.5Mbps, 216Mbps-HT/270Mbps-HT

But the same link with WDS enabled looks like this:
tcp both = 14.8/12.6Mbps, 54Mbps/216Mbps-HT, which is just bad.

I’ve tried to search for some help on the forum, but the only info I’ve found is that MT in ap-bridge mode with WDS works 50% of time as AP and 50% as Station. Is that true? If so, how can i make my WDS backbone mesh more effective? I’d like to use 2 independent wireless cards, 1 for backbone WDS and 1 for client access. Than, which moeds should the cards run? Just “bridge” and WDS for backbone and “ap-bridge” for client access?

Are there any good practices for setting up a WDS mesh backbone and client access?

Thanks in advance,

2

WDS is somehow broken with n-cards. Try using ap-bridge with station and in top of that use EoIP or VPLS.

3

Are there any good practices for setting up a WDS mesh backbone and client access?

Yep - Don’t do it.

If you want Max thruput, you need to spend more money and have AP<->Client all over.

If you want Cheapest, use Mesh and/or WDS, but there is a big performance cost.

There’s also a ‘hidden’ management cost too, 'cos in a Mesh, it is quite hard to find out wtf is happening when something goes wrong.

I am assuming we’re talking AODV or OLSR still (somebody please correct me if i’m talking bolloz)

4

@ayufan: Is it broken only with n cards, or the cost of using it is always that high, no matter what type of cards you use? And, why is the cost so gigh, how does it work, that it is that ineffective?

Yep - Don’t do it.
If you want Max thruput, you need to spend more money and have AP<->Client all over.

If you want Cheapest, use Mesh and/or WDS, but there is a big performance cost.

OK, the problem is… I really have a dynamic mesh situation, where some of the APs are mobile. Of course some are not and I can try using EoIP/VPLS there, but they are all static solutions. I need some way to get a mobile layer 2 (or 3) network, so WDS dynamic mesh with HWMP+ seemed to be ideal.

So, there is no way to make WDS more effective, even when using multiple radios?

Thanks for help!

5

Only with n. It was pointed by MikroTik some time ago.

6

If possible, use MPLS in place of WDS. WDS has an issue with one of the 802.11n packet packing mechanisms. It’s a standard conflict, we can’t fix it.

7

I use WDS with 802.11n with Nstream on backbones all the time with no problem..

8

nstreme has it’s own packing mechanism, so it fixes the problem

9

Could you please give me some clues how to do that, how are your MTs configured and how does the performance look like? I’ve tried to run WDS on Nstreme links, but with no success.

Regards,

10

Sorry to drag up an old thread but with Nstream+802.11n+WDS is this still and issue?

11

if issue will occur for ptmp links too…?

12

FWIW, the WDS problem with AP-AP links was fixed in the 5.18 release.