If I configure one sector with 120 uses (theoretical max), how is throughput and latency affected per user? What is the recommended number of connected users per sector?
This is no single answer for this question as it depends on several parameters such as duty cycle, payload size, max range, type of environment (rural, urban) etc.
There is a ePMP Link Budget Calculator Tool created for Excel available at https://support.cambiumnetworks.com/files/epmp
With this tool, you can enter in parameters specific to your situation and the tool will provide you the expected latency, throughput and other key performance indicators. Please give it a shot and let us know if you have any further questions.
Hi,
Thanks a lot for your answer. Have tried this tool out and have a couple of questions:
1. The tool does not allow me to input distribution (or physical range) of individual users. What happens with the overall system throughput if I have 10 connected clients where 9 are within 1 mile and the 10th one is 8 miles away? Is the overall system throughput decided by the 10th user in this case or can the e1000 handle that user separately?
2. As a follow-up question, is it possible in your system to configure individual bandwidths and prioritization per user? Say I have a “gaming” subscription, a “file sharer” subscription etc. If this can be done, where is it configured?
Thanks a lot for your help.
- The calculator/tool currently doesn’t support providing performance indicators for a mixed distribution. ePMP is able to determine the data rate (MCS) for each station independently. In your example, if you have 9 clients connected within a 1 mile range, it will be able to provide a higher throughput to those 9 stations due to the higher modulation compared to the 1 client 8 miles away which will most certainly be at a lower modulation and hence lower throughput. I’m guessing you already knew that. The overall sector throughput will be slightly degraded in this example since the AP will have to allocate resources to the 1 client 8 miles away to be fair to that subscriber. But in your specific example, the impact will be negligible.
2. ePMP supports a feature called Maximum Information Rate (MIR). This feature is found in the Configure–>Quality of Service menu option on the AP. You can configure up to 16 profiles and set the desired DL and UL rate for each profile. One of these profiles can be assigned to each station under the same menu option on the STA.
Prioritization per user (Station Prioritization) in not available in the latest System Release 1.1.7. But its coming soon, so stay tuned!
Thanks a lot!
Good luck getting pass 40 sub with 20 Mb download and 3Mb uploads with no issues.
@SKYNET360 wrote:Good luck getting pass 40 sub with 20 Mb download and 3Mb uploads with no issues.
Hey SKYNET, you having some issues with youro ePMP deployment? Care to share, maybe we can figure out a solution.
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Can you post some screen shots of your wireless tab on the AP? I’ve got a couple panels seeing 100+ at night without a problem.
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Hello,
Are you running a CAMBIUM EPMP2000 AP LITE 5GHZ GPS SYNC with 100+ clients on a single sector? We are looking at purchasing these antennae with the upgraded license to push the total SM's to 120 however we cannot determine anywhere what the throughput will be like if we are running 100+ clients on a single sector? ie 100 SM's each running at 20Mb/s
While I've never gotten anywhere near 100 SMs on a single ePMP sector, I'm pretty confident saying that would be a bad idea... each client certianly isn't going to be able to do 20Mbps with that many on a sector. There's no reason why you couldn't connect up to the full 120 SMs, as far as I know, but you would be severly limited by the overall capacity of the AP. If all the clients are limited to, say, 1Mbps, it would probably work fine with 100 clients on a single AP, but you're not going to get anywhere near 20Mbps to each SM at peak hours.
If you're expecting to have that many clients on the APs, I would seriously consider using sector antennas with narrower beamwidth, and splitting the clients between several APs. For example, you could use something like the RF Element horn antennas, and do three 30 degree sectors instead of each 90 degree sector and (assuming the customers are fairly evenly distributed) drop to 30-40 customers per AP, which will work quite well.
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I had an AP epmp1000 gps with 70 customers between 2-3 km, all at MCS13-15. No interference. Customer speed 5 or 10 mbps DL, 1-2 UL.
Performance never passed from 50 mbps. GUI unresponsible, AP very slow with some lockout.
Finally put a 2nd AP and now have 35 customers on each. Working correctly. Now each AP is moving 40 mbps on average.
It seems there isn't enough cpu for customers REAL traffic (pps?), not syntetic nor stress tests.
Regards
Antonio
Around 50Mbps is the most I've seen through a single PtMP ePMP 1000 AP, but in our case, I have no reason to think it was trying to do anymore than that, since the AP isn't that heavily loaded.
In a point-to-point setup, they're certainly capable of a lot more than that.... we had an ePMP PtP link that was doing close to 100Mbps daily, before we replaced it with a higher capacity link, and I have seen several other PtP links do well over 50Mbps with real traffic.
Samuel A wrote: What happens with the overall system throughput if I have 10 connected clients where 9 are within 1 mile and the 10th one is 8 miles away? Is the overall system throughput decided by the 10th user in this case or can the e1000 handle that user separately?
Hi Samuel - in addition to what Sri already answered, it's important to also note that Cambium has some significant improvements over the standard WiFi or UBNT handling of near and far clients.
With WiFi for example, a packet is sent out and an ACK needs to come back from that client before the AP can move on to handling the next client. That can (as you say) dramatically impact the AP's performance with that 10th client out at 8 miles.
With Cambium - the AP knows how far each client is and the 'scheduler' basically does this.... the AP transmits to each SM in it's own scheduled time slot - but it doesn't have to wait at that instant for ACK's. As part of the 'schedule' that was previously sent to each client - each client knows when to expect it's download data, AND it also knows when it should later send back it's ACK. So - the AP basically does all the TXing in the most efficient method possible (client1, client2, client3, etc) and then in a very quick interval later - the AP knows when the ACK's are later going to be due back from the clients and it can listen for them all in turn - ACK1, ACK2, ACK3,etc all packed together as neatly as possible.
So, the negative effects of a near-far situation are significantly reduced by Cambium. There is (of course) still the issue that the far client may well be a -72 instead of a -59 like a close client is, and that will (of course) reduce the MCS - but in theory if you used a large enough antenna and get that client back to a -59 at 8 miles... the distance itself would have negligible impact on Cambium, while it can cripple a WiFi or other type of AP. :)
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It is Base Station ePMP 1000 GPS Sync with 120 CPEs ( on screenshot - 106 CPEs online). TDD DL/UL -Flexible, frame 5 ms.
Sector load in 20 MHz
Latency ( ping) in 20 MHz
.
40 MHz channels.
Service plan is 5 Mbps in 20 MHz , 10 Mbps - in 40 MHz.
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It is ePMP 2000 with Smart antenna, 100 CPEs. TDD UL/DL Flexible, frame 5 ms.
20 MHz channel - daily sector load - max 54 Mbps, OOKLA speedtest from clent in the evening ( peak sector load) -4.8 Mbps ( Service plan - DL 5 Mbps , UL - 2 Mbps ).
40 MHz channel - daily sector load - max 79 Mbps, Link Test and OOKLA speedtest from clent in the evening (local time GMT+2 hours - peak sector load) -8.55 Mbps ( Service plan - DL 10 Mbps, UL -2 Mbps), latency -average 53 ms.HD video ( 720p) for any of 100 clients is available in any time , also on peak sector load on weekend.
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