Wireless Service Providers → Question on Bandwidth Management

All the bandwidth management boxes i have seen sit on the back end and can assign upstream/downstream for each MAC. This is fine, but my concern is on the wireless side.

Perhaps i am not understanding right, but if i have 10 users on 1 AP, and 1 user is using kazaa or streaming video, etc, even if i cap his bandwidth at the router, wouldn't he still be monopolizes the entire wireless channel?

Is there a way to cap wireless bandwidth such that he has an equal share with the other 10 users on the AP regardless of what applications he is running?

Thanks!

I think you may want to look at CPE radios/routers that can bandwidth limit.

Think the tranzeo line can and I know the demarctech mcpe and the teletronics cpe have this feature. There are several more I am sure, just do not remember of the top of my head. Also if you like to build them yourself, the star-os and mikrotik software can do this.

Are you saying i should limit the bandwidth at the CPE, not the AP?

I never thought of that... Are the CPEs you mentioned indoor units? Because my entire implementation is within 1 Apartment building with many tenants.

thanks-

Oh, but also, why are all the bandwidth management units separate servers if they cant alleviate over the air bandwidth?

Limiting at the CPE is my choice, but I am sure others have great points about limiting elsewhere. I do not have any white papers or some calculations proving it is the best thing to do, but I would think limiting at the AP would not totally solve the problem like you mentioned. If I am not limiting at the source I have to drop the packets at the AP and then deal with the re-transmits.

Now using something like a traffic shaping devices at the AP or in the NOC I can also see as a benefit. You could then offer higher speeds, but throttle back when a sustained rate is flowing for more then a few minutes.

So is there any usb/wireless indoor cpe (under $100) that let you control bandwidth?

This is not a WISP implementation, rather an indoor MDU implmentation so $300 per subscriber is too much.

For any TCP application, you can limit the bandwidth at one part and it will limit it everywhere. Almost all applications are TCP. Basically what happens is that slowness at one point will cause the entire connection to run slow.

So you can limit at the head end and it will not "flood" the wireless side.

You're problem in doing it that way isn't legitimate traffic, it's virus/ddos traffic which uses UDP which will flood everything it's connected to. So to really effectively limit you would need to do it at the CPE.

Does there exists a cheapy (linksys,dlink,netgear, etc) client device that lets me throttle bandwidth?

said by abenyukh:

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Oh, but also, why are all the bandwidth management units separate servers if they cant alleviate over the air bandwidth?

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Just to cover this, the way that TCP/IP works, it does not send more data until it has received an acknowledgement. Of course UDP is much different, but few things truly run on UDP. I wouldn't use a UDP p2p application, because there would be no error correction! However, what this does mean, and I have executed it flawlessly here, is that I control all bandwidth on my end of the connection. I have wireless customers, DSL customers, all running at 2mbps-11mbps, depending on where they are at, and I use a Mikrotik box to control the bandwidth. They are not flooding the wireless channel, because of TCP/IP's acknowledgements, so it works fine. As far as limiting on the far side, the Karlnet software does have bandwidth management built into it, however, it is a flat asynchronous speed, so you will not be able to set separate up/down rates.

Just as a tip: Study the TCP/IP protocol more, and you will find that it is a very smart protocol, capable of overcoming most every problem you could imagine.

said by rantou:

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Just as a tip: Study the TCP/IP protocol more, and you will find that it is a very smart protocol, capable of overcoming most every problem you could imagine.

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Yeah..every problem `cept how to get broadband out at my house. :\

None of the cheap client devices do much of anything besides bridge the connection. If you are trying for cheap then I would recommend sticking with a head end limiting device. They work well unless you run into the UDP flooding problem both myself and rantou described is possible, but you could allways shut that customer off until they correct their problem. (That's what we do now.)