I have a big problem.

My network structure:

A-B-C-D-E-Internet
(A-E are MT routers with wlan links and OSPF routes)

The bondwidth is form A to D is 10/10 Mbit/s
and from D to E is 15/15 MBit/s, but

From A to E is only 0,5/0,8 Mbit/s!!! Why?
Help!

I'm assuming you're running single-WLAN routerboards with WDS.
Each time your data hops on one access point,
your bandwidth throughput essentially gets halved. (Ignoring processing time)

Starting with 10mbps:
By the time you get from A to D, you only have 2mbps theoretical throughput.
Half that once more, for the D to E hop, and you're left with 1mbps.
So 0.5 to 0.8 doesn't seem too far off.

If I'm horribly wrong here, someone let me know -
that's how I understand WDS-based networking.

Cheers
-K

Every Routers are P4 3000 Intel PC.
No WDS mode, every routers running single Nstreme mode,
different frequency.

How many radio devices are there on each router?

2-3 radio devices (r52, cm9)

Perhaps signal loss happening somewhere?

Every signal is -62 , -68.
But, I found the problem.
In C router are 2 radio device, different ferquenci,
5250 and 5290 (Turbo).
I changed 5290 -> 5760 and the problem ended.

But every 20/20 Mbit/s links in not 20/20 MBit/s A-D only 9/9 Mbit/s.

THX

I have the same problem
I use p3 900Mhz

Pc1(1wlan)---Pc2(2wlan)---Pc3(1wlan)
I use 2.4 freq (my bad luck I have only 11 channels)

Pc1-Pc2=15mbit (-68,-69)
Pc2-Pc3=20 mbit (-62,-64)

Pc1-Pc3=2-4mbit

is there possibility that 2 wlan's(pci) on pc2 may interfere them self’s because there are in the same pc-case, I mean there are connected on the same metal case- they have same accumulation? (sorry it's difficult to explain in English )

Try checking the CCQ's of each link while running bandwidth through them. If any or all of them are low, that could be the problem. If they are all good, chances are it's not related to any of the wireless links.