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WirelessRudy
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Max CPE's on one AP. Experiences please!

Sun Mar 06, 2011 3:56 am

I am thinking of setting up a new tower that has to serve at least 100 users.
Each user is allowed to download with 4Mb, so I must be prepared to run at least 40Mb down and some 10Mb up simultanously. (My present network with 200+ users with same subscribed speeds does never produce this, 25 down and 6 up is max I ever saw. But ok, future will see more demand....)

Since ´seen´ fm tower all these clients are in 45 degrees sector at some 2 to 4 km distance and I want to save as much spectrum as possible I am thinking of only one rb800 with one sector and nv2 or maybe one rb800 serving two AP's serving same same clients.

Tower also has to carry 3 or 4 backhaul links and all have to be in 5ghz ´upper´ band (5500-5700Mhz) which leaves me only 11 channels to use.
Experiance is that either nv2 or ´n´ need 40Mhz channel for seemless working I am limited in the amount of AP's I can setup. Basically I have only 6 channels with such spacing. (But I also have other towers in ´reach´ so they could create interference.)

So, is 100 clients on one AP possile?
Or, is 50 clients on one AP possible?

Any figures from our forum friends?
Who is serving high amount of CPE's of one AP?
 
n21roadie
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Re: Max CPE's on one AP. Experiences please!

Sun Mar 06, 2011 3:25 pm

Tower also has to carry 3 or 4 backhaul links and all have to be in 5ghz ´upper´ band (5500-5700Mhz) which leaves me only 11 channels to use.
I use at present 5ghz for both AP + backhaul, i am considering using unlicensed 24Ghz for backhaul but i believe this freq is not really suitable for long distance links but ok for 40Km or less, this will free up all of the 5ghz band for AP channel selection which maybe necessary as 5ghz gets more and more crowded, and another consideration is if your backhaul freq in 5ghz gets effected (interference or by another provider ??) it will impact on all of the AP's on the tower or next PTP this backhaul may feed?
 
WirelessRudy
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Re: Max CPE's on one AP. Experiences please!

Sun Mar 06, 2011 7:52 pm

Good thinking... but not.
Reason why most of us start using 5Ghz is to go out of the crowded 2,4Ghz band. You are an internet provider? Well, where internet it you'll find 2,4Ghz devices. I can drive 1 km in even the country side here and already picked up 10, 15 or more 2,4Ghz sending devices.
2,4Ghz band is in most urbanized areas so heavy used it becomes improper for quality provider to use it for their services. Only in desert like populated areas 2,4ghz could still be a choice.
Also, 2,4Ghz also is only 60Mhz wide which leaves you ample spectrum for proper backhauls.
 
mbsteez
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Re: Max CPE's on one AP. Experiences please!

Sun Mar 06, 2011 7:56 pm

He said 24 GHz, not 2.4 GHz. I can't imagine you'll get much of a link at 40km with 24 GHz tho.
 
n21roadie
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Re: Max CPE's on one AP. Experiences please!

Sun Mar 06, 2011 8:19 pm

He said 24 GHz, not 2.4 GHz. I can't imagine you'll get much of a link at 40km with 24 GHz tho.
Yes i did say 24Ghz and most of my links are less than 10kms and some will be less than 20kms, but i haven't seen any reports about the useful distance of using 24ghz with 35 or 40dbi antenna, i wish someone would post a actual test distance report?
 
fewi
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Re: Max CPE's on one AP. Experiences please!

Sun Mar 06, 2011 8:41 pm

 
WirelessRudy
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Re: Max CPE's on one AP. Experiences please!

Sun Mar 06, 2011 10:33 pm

Sorry for my misread.
I've seen these Ligo's, very interesting but way out of my budget for now. Would be ideal though since my links are all in 2-8km range...
 
ste
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Re: Max CPE's on one AP. Experiences please!

Sun Mar 06, 2011 10:53 pm

Sorry for my misread.
I've seen these Ligo's, very interesting but way out of my budget for now. Would be ideal though since my links are all in 2-8km range...
May be going direct to SAF is cheaper ...
 
WirelessRudy
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Re: Max CPE's on one AP. Experiences please!

Mon Mar 07, 2011 1:22 am

SAF?
 
ste
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Re: Max CPE's on one AP. Experiences please!

Mon Mar 07, 2011 8:34 am

SAF?
SAF Tehnika. The manufacturer of this device.
We use their 18/38GHz devices. Love it.
 
n21roadie
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Re: Max CPE's on one AP. Experiences please!

Mon Mar 07, 2011 1:51 pm

SAF Tehnika. The manufacturer of this device.
We use their 18/38GHz devices. Love it.
Are these licensed frequencies and what cost how per year does it cost to renew licence, as we expect to pay €1200 per year?

http://www.stelladoradus.com/24GHz.poin ... t.link.php
If this unit had a higher gain antenna, could be worth checking out for 2-8km links?

Or this AirTik using Mikrotik to upconvert to 10Ghz
http://pojitko.cz/
 
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Re: Max CPE's on one AP. Experiences please!

Tue Mar 08, 2011 8:24 am

I would like to remind all of you of the forum rules:
http://forum.mikrotik.com/faq.php#f0r0
 
WirelessRudy
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Re: Max CPE's on one AP. Experiences please!

Wed Mar 09, 2011 2:42 am

My original request no anwered by anyone... do we all keep this a secret?
 
ste
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Re: Max CPE's on one AP. Experiences please!

Wed Mar 09, 2011 10:14 am

My original request no anwered by anyone... do we all keep this a secret?
Depends on ... is the answer. We've a rule of thumb to put up to 25 cpes to
a 5ghz sector for good user experience. We've had up to 60 on a sector
without problems using plain 802.11a. This depends on users.

Using nstreme/nv2 might increase this numbers but you need a clear spectrum
for this. As 5.x rcs rolls out this might change with every version.

Using Rb800 with multiple interfaces you may get reduced numbers due to
self interference.

Using backhaul in same band may increase self interference and decrease
numbers.

Mounting with good spacing reduces interference and increase numbers.

Working with different polarizations reduces interference and increase
numbers ...

So it realy depends ...
 
WirelessRudy
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Re: Max CPE's on one AP. Experiences please!

Wed Mar 09, 2011 11:31 am

I all agree on that, and basically know that.
I am just wondering what biggest amount of CPE's have some of our fellow forum users..

I already found that although nv2 is doing a good job in serving many clients on of one AP while the ´hidden node´ is common I also found that by using nv2 on a channel it is effecting channels up to 20Mhz away. So adjacent channels on some tower, or in line of sight of the antenna's should be avoided.

On this moment I have a tower with a single omni that already has 28 clients. Another 6 or 8 are scheduled to move to this tower too while we are still getting new clients in its reach region. I am wondering up to how much I can go on in putting more CPE's to this tower before I really need to split one AP in two or three.
But splitting means use of more freq's and this tower already needs 3 backhauls while it is amidst a zone where it picks up 5Ghz signals from at least 5 or 6 other antenna's in the region...
So, preferably I would like to use as less AP's as possible which means they have to be loaded as much as possible to serve my clients.
Most of my clients are allowed 4 Mb download with some burst while on average I hardly ever see more then 10% of users of a tower `online´ at the same time. My AP's are rb433AH's and I never put more then two radio cards in one rb. So I am hoping I can do with approx. 50 CPE's on this omni before I am forced to find another solution....
 
n21roadie
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Re: Max CPE's on one AP. Experiences please!

Wed Mar 09, 2011 12:10 pm

Since ´seen´ fm tower all these clients are in 45 degrees sector at some 2 to 4 km distance and I want to save as much spectrum as possible I am thinking of only one rb800 with one sector and nv2 or maybe one rb800 serving two AP's serving same same clients.
Am i reading your post correctly as using FM Broadcast tower as new location or "Since seen from Tower"?
Last edited by n21roadie on Wed Mar 09, 2011 12:40 pm, edited 1 time in total.
 
ste
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Re: Max CPE's on one AP. Experiences please!

Wed Mar 09, 2011 12:34 pm

I all agree on that, and basically know that.
I am just wondering what biggest amount of CPE's have some of our fellow forum users..

I already found that although nv2 is doing a good job in serving many clients on of one AP while the ´hidden node´ is common I also found that by using nv2 on a channel it is effecting channels up to 20Mhz away. So adjacent channels on some tower, or in line of sight of the antenna's should be avoided.

On this moment I have a tower with a single omni that already has 28 clients. Another 6 or 8 are scheduled to move to this tower too while we are still getting new clients in its reach region. I am wondering up to how much I can go on in putting more CPE's to this tower before I really need to split one AP in two or three.
But splitting means use of more freq's and this tower already needs 3 backhauls while it is amidst a zone where it picks up 5Ghz signals from at least 5 or 6 other antenna's in the region...
So, preferably I would like to use as less AP's as possible which means they have to be loaded as much as possible to serve my clients.
Most of my clients are allowed 4 Mb download with some burst while on average I hardly ever see more then 10% of users of a tower `online´ at the same time. My AP's are rb433AH's and I never put more then two radio cards in one rb. So I am hoping I can do with approx. 50 CPE's on this omni before I am forced to find another solution....
40 clients on an omni can be satisfied if there are no power users.

If spectrum is your problem you might consider using 10MHz channel size and split users to 2 APs.
But the biggest gain you can get is doing your backhauls in another band. Doing backhauling in a
saturated band gives bad quality to all users. Every additional ap can kill your overall quality.
 
WirelessRudy
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Re: Max CPE's on one AP. Experiences please!

Wed Mar 09, 2011 4:33 pm

40 clients on an omni can be satisfied if there are no power users.

If spectrum is your problem you might consider using 10MHz channel size and split users to 2 APs.
But the biggest gain you can get is doing your back-hauls in another band. Doing back-hauling in a
saturated band gives bad quality to all users. Every additional ap can kill your overall quality.
With "no power users" you mean that the total traffic of 1, 2, 4 or any is not becoming that big the router can't handle it?
I understand that when only one or two CPE's would try to access medium all the time because they want big file downloads the other CPE's stand less change to get medium access time. (802.11 network)
But as I understood nv2 should make sure even idle CPE's get their assigned media access time. Hence with nv2 AP should be able to serve more CPE's compared to 802.11.
So it must be you mean ´the maximum throughput´ a router can handle anyway?

I am trying to convert existing AP's to run in 10Mhz band but with some people switching their CPE's off while not ´online´ this is very daunting. 8) ALL stations have to swap to 10Mhz at the same time as the AP... One that was not ´on´ during the swap won't be able to associate in the now running 10Mhz AP.

Backhauls in other bands. As soon as the money becomes available for that we probably go that way. But we first need to make the money to get that far..... so I have to do it with the present means and network so I have to squeeze every possible option out of MT's 802.11 system (with nv2, ´n´ links, 10Mhz etc. etc.) to allow me to handle more clients that have to bring the cash in for other, more expensive, stuff.
 
ste
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Re: Max CPE's on one AP. Experiences please!

Wed Mar 09, 2011 5:10 pm

With "no power users" you mean that the total traffic of 1, 2, 4 or any is not becoming that big the router can't handle it?
I understand that when only one or two CPE's would try to access medium all the time because they want big file downloads the other CPE's stand less change to get medium access time. (802.11 network)
But as I understood nv2 should make sure even idle CPE's get their assigned media access time. Hence with nv2 AP should be able to serve more CPE's compared to 802.11.
So it must be you mean ´the maximum throughput´ a router can handle anyway?
This is not so simple. If you've perfect conditions and nv2 would do exactly what it wants to do
you're right. But you'll see changing speeds and you see torrent-users do more harm than users
who use normal ftp at full speed.
nv2 should serve more users but it's still in development. Each time I tried it I got better results
using plain 802.11 (did not try it with the last 3 betas). I believe nv2 needs clean spectrum for
good results and following some posts it is better to limit the speed to avoid up/down scaling.
I am trying to convert existing AP's to run in 10Mhz band but with some people switching their CPE's off while not ´online´ this is very daunting. 8) ALL stations have to swap to 10Mhz at the same time as the AP... One that was not ´on´ during the swap won't be able to associate in the now running 10Mhz AP.
There was a post with a script trying 10/20 Mhz to connect. Putting this to all clients ...
Backhauls in other bands. As soon as the money becomes available for that we probably go that way. But we first need to make the money to get that far..... so I have to do it with the present means and network so I have to squeeze every possible option out of MT's 802.11 system (with nv2, ´n´ links, 10Mhz etc. etc.) to allow me to handle more clients that have to bring the cash in for other, more expensive, stuff.
Then I would try with different polarizations. E.g. use Horizontal for backhauls and vertical for APs.
This gives you some additional signal separation.