I have seen a similar thing. If you do a speed test using RouterOS built-in test try changing the packet size to 200-300. As far as I can tell, this is a truer representation of normal internet traffic and does drop the throughput considerably.
M3P is a good way around this as it will aggregate all the small packets into a 1500byte packet. I have run the test using 200-300 byte packets on a M3P link and it gives similar results to a 1500byte test (i.e. full throughput). There is of course always a down side. With M3P it will wait up to 15ms to fill that 1500byte packet and therefore adds delay. The impact of this is that if you normally ping across a link with 1-2ms you will now get +30ms (15ms on sending the ping and another 15ms on the reply) but when there is traffic on the link this delay reduces as the 1500byte payload is being filled quicker. I have posted a request to Mikrotik to make M3P's 15ms timer user configurable as I think a delay of 5ms should be plenty to fill the 1500byte payload during heavy traffic whilst the feature isn't really necessary during quiet periods. As per normal, I am yet to get any response from MT :( Give it a go and let us know if it helps. Cheers, P. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of David E. Smith Sent: 28 October 2005 18:45 To: email@example.com Subject: [WISPA] Real-world RouterOS tuning (or, Atheros/RB532 redux) Okay, I'm a bit puzzled here, and since there are a few folks out there playing with these, maybe you'll have some advice. I just put up a pair of RouterBoard 532s for a heavily-trafficked backhaul link. It's about as simple a setup as you can get - just Ethernet up to one Atheros, running as an AP, across a 1/2 mile link to a client, back down the Ethernet. Simple enough, eh? Since it's just one radio hop, I haven't set up WDS or anything fancy, just a few simple routing statements to direct traffic from one end to the other. Using the RouterOS built-in tests, this link claims to be capable of almost 40Mbps one-way. I know the tests are somewhat idealized, and probably a bit optimistic, but I'm having trouble getting speeds even a third of that. I don't believe it's an RF issue, because it's a short link with good antennas. Signal strength is around -58, noise is in the mid-90s. Also, when there's no other traffic on the link, I can get the same "test" performance there that I was getting on my workbench, where the built-in bandwidth tests report 35+ Mbps. It's just that the darn boards seem to choke in the face of real-world traffic. (My real traffic load is around 10Mbps aggregate, balanced about 80-20 between upload and download.) I've tried hopping around to different frequencies, which I didn't expect to help. I've tried both enabling and disabling their proprietary NStreme protocol, and enabling/disabling radio compression. I haven't yet experimented with M3P (the "packet packer protocol" option), but I'm a bit skeptical on it as well. The (informal) testing I've done thus far shows the link not really handling traffic beyond about 15Mbps or so. (The "informal" testing was done with a few Web-based speed tests. More formal testing, with tools like nuttcp or qcheck, will be coming soon, but I'm really skeptical at this point.) Any suggestions on how to further tune the performance on these boards would be welcome. Thanks! David Smith MVN.net -- "You don't seem the lying kind... a shame that I can read your mind." -- WISPA Wireless List: firstname.lastname@example.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.1.362 / Virus Database: 267.12.5/150 - Release Date: 27/10/2005 -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.1.362 / Virus Database: 267.12.5/150 - Release Date: 27/10/2005 -- WISPA Wireless List: email@example.com Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/