Just playing with queuing on wireless interface for a sector.
Target: Limit some cpes, evenly share all available bandwidth.
Limiting is done with access-list
Using standard sfq gives bad result. One limited user using all his
bandwith causes 80ms latency for all other users.
Using bfifo reduces this effect by 40ms but bfifo does not equally
share traffic. Users with multiple connections are prefered.
Using pcq with classifier dst-address does the job unless one
limited user eats up all his bandwidth. When this happens
all other users are limited to the bandwidth of the limited user.
Tested with 5rc5 nstreme and 802.11 in lab so wireless condititions
does not influence the result. Testing with 3cpes to a rb493g.
Tcp Bandwithtests are done from rb450g/rb1100 connected to the
Etherports of cpe/ap.
PCQ with mangle, address lists and que trees is probably going to be your best bet. There are a few examples on the wiki. Also as you mentioned you need to set RX/TX limits in your AP to keep the wireless side happy.
I’ve done a testsetup. You’re right. But using PCQ I cant use rx/tx access-list limits.
Doing this gives strange results. When an access-list limited cpe uses all its bandwidth
all other non limited cpes are limited to the bandwidth of the limited cpe.
Looks like access-list limits are sorted into the queue tree in some (invisible) way.
I assume from your description that you are doing everything on one router board? I have a separate router at my head end that I run PCQ on and I also run rx/tx limits on my AP’s. I have never noticed the same issue you are describing I guess because mine are on two different devices.
I guess this is the reason. My tests show that PCQ would be the best queuing
at the wireless interface at the AP. Even with a lightly loaded segment on
a rb411ah all other queue types add latency. Second best was bfifo. Standard
SFQ gives poor results.
I will do some more testing with PCQ and access-list. I want to stay with
access-list as it is the only way stopping a bad behaving customer eating
up airtime as it throttles traffic at the cpe-side.
I’ve asked MT support on the behavior of access-list/pcq but got no response
so far.
Can you explain this? How can that be?
I have several AP’s each with 10-30 cllients attached and the basic speed limit for each client is 700/4Mb (u/d) and I never see a specific client ´eating´ all airtime. If your basic connection rates are minimal 6Mb and you have RTS/CTS or nstreme or NV2 implemented I wouldn’t know how one single client can ´eat up´ all the airtime?
I have several clients using P2P but other clients are not effected by it. Even if the demand would be higher then the total available capacity. QoS takes care of that.
So none of my AP’s do have access list limit in use. Only mac address authentication.
Nothing… where is client sending these too? To the internet. In that case his speed is limited to the speed I set for him.
All that happens is that he might open a lot of connections. So limit these. But I don’t even do that.
I see sometimes a clients opens 20-30udp connections but it is not harming the rest of my network and they die almost inmediately.
Some P2P users open 20-40 tcp connections but then the total speed will never go beyond what his users queue is allowing…
Of 200+ clients I so far have never seen any problems in the 5 years I do this now.
I presume your networks consist of MT units only since accesslist limitation in AP for non-MT product don’t work. I have a mixed network so it is useless for all 3rd party users anyway…
So a customer can flood packets into your Network up to the point where your limiting
router gets in touch. A simple netcut can make your QOS go cracy.
If you have nice behaving customers this might be ok …
With tcp you’r router can slow down acknowledgement so you have a chance.
Can you explain this? What is netcut, and what can it do? If i google I only get an arp tool.
Any abusers of my network are thrown off anyway…
[quote=“WirelessRudy”]
Of 200+ clients I so far have never seen any problems in the 5 years I do this now.
I presume your networks consist of MT units only since accesslist limitation in AP for non-MT product don’t work. I have a mixed network so it is useless for all 3rd party users anyway…
[/quote]
I avoid to mix.
Well, in real life for many operators that is just not possible.