Tech Q: Internet Voice over IP, QoS

Hey, all. I hope my fellow Dopers can give me a few pointers on setting up Voice over IP.

A friend of mine wants me to help him set up a VoIP phone, and I understand a router capable of QoS will be required. Does anyone have any experience setting up such a system? If so, any comments or suggestions would be welcome.

If not, I’d be just as happy if anybody could point me in the direction of any FAQs or reference sites that deal with the specifics. I guess the tech is relatively new and still mostly confined to business use so I’m not finding much in the way of general reference sites.

QoS is not required. All you need is a broadband connection. Also, older consumer-level routers may not support the VoIP protocols properly or require a firmware upgrade to work properly, so you should check into that for whatever equipment your friend currently has.

However, QoS will help prevent dropouts and other problems that can occur when the Internet connection is busy with stuff other than the call. A non-QoS capable router has no way of knowing that the call should have priority over the MP3 download, web browsing, or whatever else might be going on at the same time.

I’m not aware of any consumer-level routers that come with QoS installed (I’d be happy to be proven wrong here). However, some people have modified some Linux-based Linksys routers to support QoS and other advanced features. You may want to look into that option:

http://www.sveasoft.com/forums.html
http://h.vu.wifi-box.net/
Or, you can go the hard way and build you own Linux-based router from scratch.

Cisco has a bunch of documentation concerning VoIP on their website:

http://www.cisco.com/en/US/tech/tk652/tk701/tech_technical_documentation.html

Sorry, I always have to toss in this little gadet:

http://www.vipernetworks.com/

Thanks for the replies. I thought I’d elaborate on my friend’s setup. He and his brother make up a tiny branch office of a small company with HQ down in New Jersey (we’re in Ontario). They essentially sent him the phones and told him to hook it up. My friend asked me to help out in order to save the expense of getting a consultant in (in his case, I’ll work for beer). I’m not a pro Sysadmin but I’ve had a fair amount of experience setting up and maintaining small business LANs so I’m confident that I can help him out, except for one thing: I can’t get any useful info out of anybody.

I don’t know the service that HQ subscribed to down there and the phones they sent have a wonderful manual detailing all of the cool functions of the phone yet it conveniently doesn’t say a word about setup and configuration. And so far, I’ve been unable to contact HQ’s own tech consultant. As a result, I’ve been flying blind and doing advance research is proving awkward. At the moment, I’m under the impression that I’ll have to setup a VPN connection either to HQ or the phone service. Is that the case?

Also, it looks like I’ve found a consumer level router that can do QoS, the Linksys BEFSR81. Does anyone have any comments on this?