VOIP: now, where do I plug in my computer?

March 7, 2005 5:04 AM

I just received my second install kit for VOIP, but unlike Episode I, there's no second LAN jack for my computer on the phone adapter.

I just received my second install kit for VOIP (VoicePulse; BroadVoice/Vox didn't sound good enough). But unlike Episode I, there's no second LAN jack for my computer on the phone adapter. Thanks to #Mefi IRC, I know I need either a different router or a "switch," but what are the pros and cons of each solution? And why doesn't this new telephone adapter have a place to plug in my computer?

posted by ParisParamus to computers & internet (11 comments total)

Paris, do you have the model number?
posted by fake at 5:11 AM on March 7, 2005

A model number for what? I have a Westell 2200 DSL Modem + Router via Verizon, and Siptura SPA-2000 adaptor from VoicePulse. Also, yesterday was my birthday: 030663
posted by ParisParamus at 5:54 AM on March 7, 2005

I think the lack of a second jack just means it's an older or less-sophisticated model. There are two basic ways that the VOIP box can be hooked up to your local home network:

1) It can be the first thing plugged into your DSL/cable modem, with everything else connected "behind" it. This is the newer mode, and requires the second LAN jack--the advantage is that it can then act as a gatekeeper for all the bandwidth on your network, and maintain good voice quality. (In other words, if you've got a big upload/download going on from your PC while you're on a call, having the PC traffic go through the VOIP box means that it can throttle back the UL/DL as much as it needs.)

2) The older mode means that you've got to use a router/switch to "split" the connection coming out of the DSL/cable modem, before you can hook up the VOIP box. In that model, the VOIP box and the PC are "peers"--they're both hooked up to the router, and potentially fighting for bandwidth. That setup means that the VOIP box can't ensure quality in the same way, since it doesn't control the PC's traffic. (There are settings you can make on your router to try and help, but it's still not the same.)

I've never been completely clear about the technical difference between a router and a switch, but it has something to do with the level of built-in "intelligence"...one or the other can manage traffic more sophisticatedly. Basically, though, almost all the simple home networking boxes being sold are "routers", so you can't really go wrong if that's what you get.

It's important to note that most home network routers also have additional features that mean you might want to get one, even if you do switch to a newer VOIP box and don't technically need it. Not only will most of them have wireless transmitters built in, which is nice, but they also add a hardware firewall to your network, which is _really_ important. For that reason alone, if you don't have one already, you should seriously look into getting one.
posted by LairBob at 5:55 AM on March 7, 2005

Buy a $50 linksys 4 port router to connect behind the DSL modem, then connect your computer and VOIP box to the router. This will keep your machines off the internet and behind the firewall of the router, and let you share the connection with more devices.
posted by mathowie at 8:36 AM on March 7, 2005

Mathowie's got it right. This is the cleanest, easiest way to do it. And actually, that 4-port linksys router is often on sale at Staples or OfficeMax for less money than that.

the advantage is that it can then act as a gatekeeper for all the bandwidth on your network, and maintain good voice quality. (In other words, if you've got a big upload/download going on from your PC while you're on a call, having the PC traffic go through the VOIP box means that it can throttle back the UL/DL as much as it needs.)

LairBob, I doubt, highly, that this is likely. The router would have to have a QoS capability built in, and be able to sniff the difference between voice packets and data packets. These are not common, and the ones that can do it are quite expensive and not normally used in the home market.

I raise the issue, because if you have this scenario working, I'd really like you to contact me offline because I need to see how you're doing it - I need this capability and to my knowledge, it doesn't actually exist in the form I need it to.
posted by TeamBilly at 9:27 AM on March 7, 2005

TeamBilly, that's apparently exactly how it works, at least from what Vonage has told me, and what I've been able to suss out on my own afterwards.

I actually don't have that setup myself, since I've been using Vonage VOIP for a little over 2 years now, and the VOIP box is what I described as the "older" style. Before I switched from DSL to cable, though, I was having quality issues, and when I called Vonage, they basically offered to sell me a newer, upgraded box with built-in QoS for about $100. The tech guy basically explained it to me in just the terms I described.

I did look into the basic premise at the time, though, and it doesn't seem all that far-fetched. After all, the VOIP box _doesn't_ really need to do any packet-sniffing--it's generating and receiving all the "voice" traffic itself. _Any_ traffic that comes in from the network connection behind it would just be "data" that's competing for bandwidth, and it would just have to regulate what it passes through from that external jack.
posted by LairBob at 10:06 AM on March 7, 2005

Cool. If Vonage is doing QoS with their ATA units then I need to make some phone calls. Thanks for the tip.
posted by TeamBilly at 1:33 PM on March 7, 2005

I don't know if anyone is still reading this, but any recommendations re CORDED phones that work particularly well with VOIP? I'm not sure why the VOIP would make a difference, but I need a new phone, I've discovered....
posted by ParisParamus at 7:45 PM on March 7, 2005

Just for reference, as far as I know,
router: an actual general purpose computer which has interfaces (e.g. cards) connected to multiple subnets (e.g. LAN & Internet).

switch: a device that does nothing but route traffic from one subnet to another, with varying amounts of intelligence (i.e. some balance bandwidth, some provide some firewalling, etc). Generally they have an IP address on every subnet they're connected to unless they are doing wacky bridging or something.

hub: a device that connects various interfaces to each other, i.e., no intelligence. no IP address, since all it does is forward packets.

I could be wrong, but I don't think I'm wildly off base.

Anyway, your ISP really ought to have told you what you need, here. If they provide you with enough IPs for all your devices, all you need is a hub, which is very cheap, but doesn't do any bandwidth balancing (so your VOIP quality may suffer). Some sort of router, or switch that can intelligently share bandwidth (i.e. guarantee your VOIP box 20 kbps or whatever) would probably be ideal.
posted by blacklite at 8:57 PM on March 7, 2005

Follow-up - QoS thing...

I did some checking around and LairBob is right about the QoS router from Vonage. The concept I was thinking of applied to large enterprise networks, not home users with small networks.

As far as a phone, analog is analog. There shouldn't be any difference with VoIP. Siemens, Uniden and Lucent all make nice, business-style phones for the desktop.
posted by TeamBilly at 7:22 AM on March 8, 2005

Yeah, regarding the corded/cordless phone, the bigger issue is whether or not you've got any WiFi going on in your house. Some of the newer phones broadcast on the same frequency as WiFi--I know my wireless connection goes haywire whenever we use our Siemens phone near it, but not the Panasonic. (It's not the brand--it's that the Panasonic is an older 900mhz model, and the Siemens is 2.4ghz, same as WiFi.)

Personally, for an office phone, I've got a decent 2-line corded model (home line and business VOIP), with a bunch of auto-dial buttons. I got a decent amplified headset from Plantronics, and it works totally fine. (My office phone actually has a little jack for a headset, like you find on mobile phones, but that's not an amplified signal. You're much better off with something like this, which you can find for a lot less on reseller sites..)
posted by LairBob at 4:12 PM on March 8, 2005