ubiqutui XM and XW performance: anyone?


I recently upgraded few APs from Rocket M5 to EPMP1k / EPMP2k, then the CPEs, ubiquiti XMs and XW have been elevated (NAT router mode).Each AP has 15-30 CPes and distances < 2km. Signals are good. Working on 20 MHz channel size. Quiet zones.

I'm interested in knowing how far have people gone in bandwidth plans for elevated ubiquitis XM/XW. At the moment I'm selling 10M download / 1 M upload but interested in going up to 30 mega download/3 mega upload.

Are these ubiquitis able to service these plans? What is the maximum expected bandwidth I may get from the AP ??

In the EPMP1K APs I have seen aggregated BW up to 55-60 Mbit/s but no more.. In EPMP2K with cambium cpes (epmp1k & force180) I have seen up to 70-80 Mbit/s but no more..  Are these maximum figures I may get with the APs??



Hello, these are all good questions and I will default to the feedback from other users for production numbers.

In general (on ePMP1000/2000), there is about 100Mbps of shared throughput in a 20MHz wide channel (2.5ms frame and long guard interval) and in ideal conditions (MCS15 for DL/UL).  This can go up to ~125Mbps using 5ms frame and short guard interval, but Elevated SM's typicaly require long guard interval.

We modify the 802.11 MAC to be more efficient and scalable (i.e. behave more like our PMP450 scheduler).  This allows you to put more users on an AP than most competitors and keep low, consistent latency.  It also allows you to oversubscribe the AP.  How much oversubscription is going to be a business decision, but we have some tools to help you with that.  One is LINKPlanner (more of a physical performance estimator) and the other is Capacity Planner (takes into account business rules and SLA's).  Capacity Planner hasn't been updated for ePMP3000 (MU-MIMO) but should be pretty accurate for ePMP1000/2000.

I have customers offering 50Mbps packages off of ePMP2000 AP's (20MHz wide channels).  However, there are a few factors influencing how many users you can put on an AP (all are related):

- DL/UL Modulation (ideally 64QAM for 50Mbps packages, 16QAM for 25Mbps packages).  The more SM's you can put at higher modulation, the higher number of large data packages you can put on an AP.

- Distance from AP.  In general, 50Mbps ~4 miles and 25Mbps <7 miles (all ideal conditions with high gain antenna).  Using a higher gain antenna (i.e. Force200) is desireable, as the lower gain models (i.e. Force180) will be roughly half of what I stated above.

- Application.  More mission critical type of services (i.e. VoIP) typically have a lower oversubscription rate and, hence, lower number of SM's per AP.

I think you can increase the overall sector capacity closer to the 100Mbps, but it may require some physical modification to your setup (i.e. higher gain SM's) and a little luck (ideal SM locations and low noise).  However, if you are comfortable with a higher oversubscription rate, then the same capacity will translate into more users per AP.