Network speed issues

I have a 5.7BH to a Cyclone5.7 Omni. My upstream provider supplies me with a 3Mb ether connect.
My client SMs can only get 1.2 to 1.5 download max. I have tried to change the ratios to allow for more or less speeds with no change to the maximum download.
I also experience weird latency issues. The radios all show 95% to 100% link. I have noticed on some client links, the latency will run 20 to 30ms then peak up to 120ms then fluctuate then come back down…

I was told this was a limit to the 5700 equipment 3Mb aggregate. So I have replaced the Cyclone 5700AP with a moto 5750AP.
Guess what, still max downloads of 1.2 to 1.5. I currently have the AP set to 75%, the BH set to 50%.
If I connect direct to the BH I can reach 3Mb plus.
The SMs are not allowing me anything past that 1.2 to 1.5. I have tried rate limiting at the SM with the defaults and without the rate limiting at the SM. No real change, but I can dial the speeds down.
I have come across a few other posts with similar issues but I have not seen how they have fixed the issue. One member said he got his working, 'We have found that there was an error checking bit rate set, that was binding things down. ’ re: post ‘Our cyclones R choking’.
I do not have any routers in between the BH and AP. I do have a GPS sync, 3com switch and now an MRTG server(to help trouble shoot the issues).

Any and all help would be greatly appreciated!
I need to keep whatever hair I have left…

Because you’re using 5.7 for both BH and AP you need to sync both of them using a CMM, the BH must be in Master mode, and the DataDown must be set the same. If the AP’s uplink is provided by the BH, you’ll get the best performance at 50% DataDown. Setting both to 75% will result in only 25% of the BH bandwidth delivering data to the AP and its SMs.

If the AP and BH are separated from each other by significant distance, a shield or building, or you use different frequency bands, then you’ll be able to push the DataDown to 75%. You may also be able to get by without a CMM.

Thanks for the reply.
I do have a CMM device providing sync to both the BHMaster and the 5750AP on the same tower. The GPS is finding the max satellites, no noticable errors on the GPS.
The BHM and AP are seperated by approx 125ft, AP at tower top, BHM at roughly 1/3 height. The BHM is on the low side of the channels and the AP on the high side. The cable runs are below the max distance in the cat5 spec.
I have tried to set the BH and the AP to 50% each. It pretty much crippled my network with extremely slow speeds. I changed it back to 75% on the AP and at least I can get up to the 1.5 transfer rate. I am using shielded outdoor cat5.
My links are for the most part 100% up and down. There are no ethernet errors on the AP or BH.


What two ports on the CMM are your AP & BH plugged into? According to Motorola, something needs to be in port 1. I’ve never read or heard the technical reason for this requirement.

With the mismatched DataDown between AP and BH, you’re not synchronized for the entire transmit cycle. This is either part of the problem or an indication you might be able to get by without synchronization. Try setting the co-located BH to slave mode, and the far end to master with its DataDown at 75%. This will either improve your throughput or make the system unstable; maybe both.

If this BH pair and AP is the extent of your local 5.7 Canopy network, and you don’t have competitors or others using 5.7 Canopy nearby, then don’t worry about a CMM for the newly configured BH master. If making this change improves the speed while remaining stable, you could likely also get by without the CMM on the AP.

Motorola’s recommendation for your situation would be to replace the 5.7 BH pair with a different frequency band.

Do you have more than (1) AP on this tower? If so, make sure that the DataDown parameter is identical on each AP, else the timing can get screwy. Also, if there is more than (1) AP, or even if you just have a single, what is your Max Distance parameter set to? You should set its value to a little higher than the furthest SM in your network. Make sure that all AP’s have the same value for this parameter also.

I too have found that setting all AP’s and a backhaul link to 50% datadown on a CMM-timed network has provided maximum bandwidth. However, I have found that setting the Max Distance param to anything other than 14 or 15 miles takes its toll on my link tests. Links that would normally perform at 100% in both directions fall to roughly 92-95 perfect when I set the Max Distance to 1 mile further than my longest link.

The keyword to pay attention to when it comes to Canopy radios and their bandwidth is “aggregate”, and you must realize that the feature that makes the networks so stable and free of self-interference, the CMM-timing, yields a half-duplex network.

The CMM unit has ports 1 and 2 used.
I do have another user of Canopy in the area.
I currently only have 1 AP on the tower with the BH.

The max distance was set to 15miles and I changed the AP settings last night to 50% and max distance 14 miles. This seems to have changed some of my download speeds. At 50% I am getting 1.5 down and 500 up. The SM is supposed to be set for 1200 syncronous service… I will check on the SM setting for rate limiting and set it to max to see how it functions.
When I set the AP to 50% to match the BH, I lost an SM. the SM was working better when the AP was set to 75%. Should this setting change have caused the SM to fail? It works then drops.

Should transmit frame spreading be enabled or not?

Thanks again for the help!


I am sorry, I don’t fully understand your last line regarding the half-duplex. Do you mean all the equipment should be set to a half-duplex settings?

No, sorry for the confusion. Since all device transmissions are timed by the CMM, it simply means that an SM cannot transmit and receive data at the same time. It is either transmitting or receiving, which is the definition of a half-duplex connection.

It’s not like a 100 Mbps ethernet connection to a switch where you can transmit and receive data at the same time.

Transmit Frame Spreading has to do with interference. You can disable it and see if it makes a difference. In my experience, it made no differene at all, but I guess that is also dependent on your RF environment. Motorola claims that it will reduce effective throughput on your system if it is enabled.

Keep us updated.