anyone running VOIP on their network ? what solutions have you gone with how many users to you have, how does Canopy handle it…

I will be rolling out Adv AP’s on 2 of our pops tonight…

We have a switchvox PBX that I am planning to put on the network as our VOIP infrastructure.

Any suggestions ?

QOS QOS did I say QOS. Make sure the ATA at cust house taggs the packets properly. If they have a broadband router make sure it is QOS capable and prioritizes packets. then make sure high priority is enabled in Canopy and set the DiffServ codepoint’s in the module to the correct priority 6 or 7. All switches, routers CMM’s, everything between the customers ATA and the gateway it uses to interface with the telco must have QOS. If only one device in the system does not and it decides it doesn’t want to give the voice traffic priority your wasting your time even turning it on in all equipment. Get a hub take a customers ATA and plug it into the hub. Don’t use a switch. Then plug the hub into the SM. Plug your laptop into the hub. Use packetizer or ethereal make a phone call and capture some packets. Look at the packets with packetizer and see what Diffserv codepoint the ATA is tagging the packets with. Look for RTP UDP SIP you will have 2 types of packets one for the actual voice and one for control for activating and terminating the call. Make sure these codepoints are the ones you set in the modules normally 46 and 32. If you do this and your latency is low you should have no problems.

are you running on Advantage…

I have just started to upgrade to Advantage in preperation for VOIP launch.

I have a question, one of the white paper documents on the Canopy site, VOIP-Canopy, talks about voice and results conducted by a third party.

They claim an AP can handle up to 26-28 simultaneous voice calls REGARDLESS of the codec used. This does not make sense as there is a pps limit on kit. The heaviest codec will use 400pps thats 400 x 26 = 10,400pps, I Know non-advantage Canopy AP can not handle that, I don’t think the Advantage can handle that rate either (i could be wrong) and even if it could, there is a limitation of 3000pps on the BH’s unless you go to othogon OFDM which have 12,000pps.

Even then if you have 2 AP’s on a cluster with voice you will throttle the BH.

Correct me if I am wrong on the above, but I think the white paper is both incorrect in terms of codec also misleading as it does not talk about BH and in 90% of deployments the AP will be going into a BH to come back to a central switching centre.

No your a little off.

G711u uses 60.67pps each way so thats 121.34pps for full duplex.
G726 and G729 use 50.67pps each way thats 101.34pps.
Maximum downlink threwput for 1 AP to 1 SM is 1800pps
Maximum uplink threwput for 1 AP to 1 SM is 300pps
Maximum threwput for BH is 3000pps

That’s 300pps per sm and I speculate that the AP is maxed out at around 3000pps just like the BH. These numbers could be confirmed by the white paper.

G711u 300/121.34 = you could get 2 calls per SM
G726/729 300/101.34 = you could probably squeeze 3 per SM
BH at 711 3000/121.34 = 24 calls
BH at 726/729 3000/101.34 = 29 calls

you are right though even if the AP has a higher threwput the BH would be the bottleneck.

mmm… are you sure…

I read an Alvarion white paper, can send you it if you want, which stated that the codec can be configured to operate at different pps rates.

The heaviest being 400pps.

I will look more into it… I am happy to stand corrected…

I got a switchvox box (astericks) gonna start playing with it…

All of my documentation I used for research and testing is at the shop. I can varify tomorrow.

Are you saying that I can only make 2 voice calls at the same time using codec g711?

ATAs have one feature that can lower the pps load - packetization interval. Also you can bundle up to 10 simultaneous calls within one packet with g.711 or more with g.729. But you have to use asterisk with IAX trunking on both sides to do that.

IAX trunking on the canopy?