sundance-communications.com/forum Forums TDM Business Telephone Systems Inter-Tel Telephones & Systems VOIP and QOS

I have recently replaced a switch that our IPRC and LAN use to connect to the internet because the old one took a lightning hit. The new switch is a cheap D-Link switch that has 802.1p QOS ability. After noticing the other day that the IP phones became useless while someone was downloading a movie (using all available bandwidth)I realized that Inter-tel must not take advantage of this paricular QOS.

Just wondering if anyone had any info on what QOS technology Inter-tel uses or the possibility of newer firmware that allows 802.1p.
Thanks!

The way I understand it, QOS in this context is a function of the router (something you are NOT going to get from the home-grade Dlink, Linksys, NetGear, etc. routers.)

Routers are like everything else...the better they are, the more they cost. It sounds like you need a business grade router for this.

Out of curiousity, why would someone download a movie at this place?

I'm sure you're right about needing a buisness class switch that can be programed for QOS. In the future we will need to upgrade. I was just wondering about the posibility of using this 802.1p in the mean time to help out.

Oh and for the movie. One word, Employees! All of a sudden the 2 IP phones we have here had terrible latentcy. So before I called our ISP I went and looked at the cable modem and it was running at full load. Looking further into it I noticed the load coming from one of our wireless access points which then sent me looking for a laptop. Sure enough one of our employees was downloading some new movie on his break!

Ahhh...sounds like someone is on DISHWASHING DUTY!

What was the old router? Could you get a replacement from your insurance company?

That's for sure.

The old switch was just another cheap dumb switch. It wasn't enough to consider insurance!

Do you have a seperate router, Switch, and Access Point or a Wireless Router with a built in switch? Just looking at the D-Link site i see the DI-724U has QoS ability.
Some Network devices treat QoS differently then others with respect to how to configure it. I know my 3com business switches (How i do my Qos type setup) let me set the priority to an IP address (which is the Ip of my IPRC) so anything going for that IP gets priority over anything else.

This works great internally but as far as the WAN speed (if you are connecting to a IPRC through the public internet) then QoS isn't going to help as the Cable Modem and everything between office A and Office B will strip off the QoS tags.

Instead look for something with bandwidth management that will regulate the WAN bandwidth and prioritize it for your phones (usually based on IP). Some of the home routers do this and Vonage, Skype, and other VOIP home providers are growing and people want clear calls.

The "Business" Class equipment I would suggest to do this is a Sonicwall TZ170 - which is under 500 bucks. This allows you to specify a bunch of parameters on how to manage both Internal Qos and External WAn bandwidth management.
My brother uses VOIP exclusivley for his business phone needs with an Asterisk VOIP server connecting to hsi VOIP provider via a 3mb commercial cable modem. After setting up bandwith management on the WAN you can download as many moveis as you like, and once you get on the phone the movies slow down and your call is crystal clear!

Good luck!

Ahhh...the wonderfully inexact science of VOIP!

Another thing is that we generally recommend a bigger connection than cable (such as a T1).

We have set up several Intertel VOIP setups with just cable modems (one of ours has a main office in one city, the satillite office with the IP phones is an hour away!)

Thanks Beholder...it's great to get other suggestions!

After the cable modem there is a dumb switch with the IPRC and router connected to it. The router has wired devices and several access points connected to it. With it connected this way we have 1 IP address for the router and another for the IPRC.

I never relized that the tags would be removed when traveling over the internet. When we do go to set this up correctly I will look into and switch/router that can prioritize. What I would really like to do is bury fiber between the two buildings and completly solve the problems.

The 2 cable modems give us 6mbps down and 512 kbps up each so our bandwidth it pretty good for what we need.

Thank you for the info!

I agree, if you could run your own private network it would be that much easier. I'm not sure if your building has line of site - I know i've seen Point 2 Point wireless receivers that work well over short to medium lengths, be it 802.11 or another standard. This may be cheaper then fiber and offer another alternative.

Good Luck, and keep us posted. It's always nice to know how others in our same boat conquer hurdles.

- Andy

Are you trying to improve the call quality on IP phones connecting across the Internet or LAN?

From what I can tell there is no way to improve the quality accross the ISP's network. Luckily the calls stay within one node on their network so I think that I have the best situation possible as the ISP goes.

After this problem appeared from someone downloading a large movie file on our LAN and maxing out the ISP bandwidth I would like to improve the QOS of the LAN so this can't happen. I don't want to spend a bunch of money though since I think a fiber line between the two locations is in the future. Although even with this fiber line there will still need to be QOS on the LAN.