Downlink % Configurations

This might be a stupid question. Scratch that, it is, but I am curious as to how most of you are setting your percentages, based on the master/slave configuration. Example: I have a BH from which traffic flows from the master side through to the slave side, so if the % is set to 75, that would dedicate more bandwidth to the upstream?? I actually have plenty of upstream but not enough down, and want to dedicate more to down. I am assuming that this percentage is based on the direction that traffic actually flows through the system, right? So therefore, in my screnario, with the master at the opposite end of the link, that setting the % to 30 would give me more downstream bandwidth? What you guys think…

Makes sense to me. Most of our BH links are set up with a 80/20% ratio, since our customers have much higher demand for download than upload. But if you had customers with the opposite requirements, I would think you’d just reverse those percentages.

<BH manual>
Downlink Data
The operator specifies the percentage of the aggregate throughput that is needed for the downlink. For example, if the aggregate (uplink and downlink total) throughput on the module is 6 Mb, then 75% specified for this parameter allocates 4.5 Mb for the downlink and 1.5 Mb for the uplink. The default for this parameter is 75%.
</BH manual>
Downlink in this case means from the BH Master to the BH Slave, regardless of whether that may actually by “upstream” or “downstream” in your network architecture.

When setting the downlink rates on the backhauls, we use the 75/25% ratios… If I changed my backhauls to 80/20%, do I need to do the same to the AP’s, since the downlink can be set in the AP’s also? Or wouldn’t it make a difference?


I have a 20MB BH Master on the tower site and a 20MB BH Slave plugged into 100Mb Ethernet which then goes to fiber and out to the internet. I have my Master set to 70% Downlink (which I am thinking about increasing to 80%). Do I have this set right? I want a lot of download speed and a little upload, so am I thinking about this the proper way? The Master DOWNLOADS from the slave, but then UPLOADS it to the AP’s, which UPLOAD to the SM’s. So is it now Uplink bandiwidth that should be 80% because its UPLOADING to the SM’s or is it fine with the DOWNLOAD from the Slave. I’m not of sure Moto’s thinking on this one because the BH’s are doing both. I think I have it set up right though because the the Manual post (above) talks about only the link between Master and Slave. So in this case, the Slave is my internet connection, so I dedicate 70% of the Master/Slave connection to DOWNLOADING from the Slave and 30% for UPLOADING to the slave.

You have it backwards, if I understand your network correctly. Typically, BHMs mounted with APs might be set to 25% or 50% downlink.

If you have only one hop of backhaul, you can set it to 25% “downlink”, and that will then give 75% of the capacity for downstream traffic (which is going “uplink” from the BHS to the BHM and then flowing from the APs to the SMs).

If you have a double hop using BHs in the same frequency band, you usually set the “downlink” to 50%.

The reason for 50% gets a little detailed: Imagine a network like this:

SM~AP|BHM~BHS|BHS~BHM| where ~ means air and | means tower

The two BHSs in the same frequency band in the middle of the hop need to have the same transmit/receive ratio, which means their BHMs need to be set to the same “downlink” %. Since it usually makes no sense to have 75% coming downstream (“downlink” from a BHM) into a BHS tower and only 25% going further downstream (“uplink” to the downstream BHM) from that tower, the only reasonable setting is 50%.