The Phone Professor

Is Your Internet Connection Fast Enough for VoIP?

2008-03-27T22:44:13Z

Are you thinking of ditching your old wireline telephone and going exclusively with a Voice over Internet Protocol (VoIP) telephone, sometimes called an Internet phone? Your Internet service provider needs to meet certain requirements. One is raw bandwidth--the carrying power of your uplink and downlink. Be careful here--often what is advertised is the downlink speed--sometimes the uplink speed is much slower.

An Internet phone will require about 90 Kbps (kilo bits per second) both up and down. If your broadband link is faster than this, you may be ok on the bandwidth front. But note--if your link isn't much faster, and another person in your household who is sharing the line with you starts a download, for example a song for an iPod, this can cause voice quality issues, including stuttering and occasionally completely dropping the call.

But there's more. In addition to measuring bandwidth, one also needs to know the latency. The latency is how long it]]>

takes to get a packet (a small piece of information--the basic package carried on the Internet) to get from your place to wherever the VoIP provider's servers are. There are a number of ways to do this. If you're brave, you can use the Command Line in Windows. To do this, click Start, then click Run, type the letters "cmd" (without the quotes), and press enter. Then, at the prompt (which ends in a greater-than sign -- >) type the letters "ping" followed by a space, followed by the name of some website, for example, www.yahoo.com. You'll get four lines of information back. The screen will look something like this:

Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

C:\Documents and Settings\Administrator>ping www.yahoo.com

Pinging www.yahoo-ht3.akadns.net [209.191.93.52] with 32 bytes of data:

Reply from 209.191.93.52: bytes=32 time=88ms TTL=57
Reply from 209.191.93.52: bytes=32 time=123ms TTL=57
Reply from 209.191.93.52: bytes=32 time=98ms TTL=57
Reply from 209.191.93.52: bytes=32 time=130ms TTL=57

Ping statistics for 209.191.93.52:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 88ms, Maximum = 130ms, Average = 109ms

C:\Documents and Settings\Administrator>

What you're looking at is the "time" variable. This lists how long it took for your computer to talk with Yahoo's server and then for Yahoo's server to talk back to your computer. It's measured in milliseconds (thousandths of a second). In the example above, those times vary quite a bit. If they're too long, VoIP won't work.

There's an easier way. Simply go to http://www.testyourvoip.com and perform the test. This site measures quite a variety of qualities and gives you a general score.

Try it out and see! The test is not perfect, but it's interesting information. Where did I find out about this link? From my VoIP provider, AT&T Callvantage.

Viack Web Conferencing Capability

2006-05-10T14:23:25Z

You've heard about Internet phones, right? There's everything from Skype, which allows you to talk to someone halfway around the world using your PC for free, to services such as AT&T CallVantage, which uses your broadband but allows you to use your regular phone handset and gives you a telephone number anyone can call. Well, there's another way to talk. Are you old enough to remember Picturephone? (I'm dating myself.) It's a service that AT&T tried to offer back in the 1950s, but technical issues got in the way.

No more! Web conferencing with audio and video is here! Several vendors offer this service. One is Viack, a 100-person company with offices in Redmond, Washington (sound familiar?), Phoenix, and Washington, D.C. Their service, at $95/month per concurrent conference user (list price--they can negotiate discounts depending on how much business you offer them) offers audio, video (using your webcam), shared whiteboards, screen sharing, and some limited collaborative capabilities.

]]>

I tried Viack (www.viack.com) a few days back, under the careful eyes of Michael Marmolejo and Kris Cobb from Viack. The download is simple--a 12.5 MB client that shouldn't take too long if you have broadband, which you need anyway in order to use the service. Make note: their software, VIA3, only works with Internet Explorer, so don't make that icon go away after you install Firefox!

You'll need at least 256 KBps down and 128 KBps up for the service to work, although I think I'd recommend more. I have twice that here in Ridgway, and found the service quality excellent.

Once you sign in, you can see which of your buddies are on line. The first level of service is instant messaging (think like AOL Instant Messaging, except without the ads). Next, you can click on one of your buddies (they must also be signed up for the service), and propose an audio/visual meeting. Once the meeting is set up, you see video of each of the participants on the left side of your screen. I was favorably impressed by the video, which uses H264 compression, the latest available. The video would lock up occasionally, probably due to my limited bandwidth line, but when the video moved it was sharp and clear.

You see all the participants at once--Mike, Kris and I all appeared together. It's nice to see yourself and make sure you look interested in the proceedings! The rest of the screen is devoted to screen sharing, called LiveView. The conference moderator can share applications, such as PowerPoint, and everyone can see it. One downside--during a Liveview session, the video for the person sharing the application will lock up. This is a "feature." It's too bad, because I'd like to see the presenter's body language.

There's also a whiteboard, which anyone can draw on. There is also a limited capability for collaborative work (anyone can participate) if you have Windows or PowerPoint. Note: You need Windows 2000 or later--it wouldn't work with my old Windows 97. Mike and Kris also tell me that the PowerPoint collaboration is "limited," but since my PowerPoint is also old, I didn't find out just what that meant. However, I've found in previous web conferencing work that if several people watched while I typed, they could tell me what to do (and they did!).

I was very interested in the audio delay. Mike and I started off on the plain old telephone, while he walked me through setting up the software. Once we had it running, I could hear him both on the telephone and on the computer. There's about a half-second delay over the computer. While this doesn't seem bad, make note that when people get hot and heavy in a conference setting, they're going to want to interrupt each other, and the delay can get in the way. I find this is true even with an Internet telephone, with about a quarter-second delay. So, beware--your participants will need to learn some phone courtesy to keep from stepping on each other. Other than the delay, I was very impressed by the audio quality--no dropouts and good fidelity. I used the headset that came with my Dragon Naturally Speaking software. You'll probably want to use a headset too.

Viack touts their security. They've put considerable effort into making sure that no one else can butt in on your meetings. This has a downside: if you forget your password, they can't recover it for you. Keep that in mind.

I should explain the $95/month/concurrent user part. That means if you're a small business with, say, 100 employees, and you sign up for the service, Viack will track the number of people using the system. If your usage peak out at 20 people using AV conferences at one time, you're charged for 20 x $95. The instant messaging part is free, so all 100 employees can use that at once without jacking up the price. As far as I could tell, the Viack instant messaging is not interoperable with any other provider's IM services, such as AOL.

Another downside: The software is downright sticky. Every time I boot up my computer, it insists I sign in. And, it puts an icon in the system tray. That might be nice if you use it constantly, but it is rather intrusive, in my opinion.

Bottom line: High quality audio/video/web conferencing with a simple price structure with good security. There are some features lacking, such as the ability to use your cursor freely on another person's computer, which would help in truly collaborative application work. It would also be nice if it worked with Firefox. It's rather pricey, but again, take your business case to Kris and see what she can do for you.

Purpose of this Site

2006-03-29T00:39:01Z

Ever wondered about phone service? It used to be so simple! Just talk to the phone company and get a phone. Not anymore! There are dozens of options, from cellular and internet phones to the Plain Old Telephone Service (POTS, and yes that's an industry acronym). The purpose of this site is to provide straightforward talk about phones. All types of phones.

The telephone professor is Dave Casler. That's me. I've been playing with phones since I was a kid, and that's getting to be a long time ago. I've watched the industry for years. I'm an electrical engineer, so I even know how phones work! This site has articles on every aspect of telephones, and is growing all the time, so come back frequently. The site is a two-way dialog, so feel free to comment on any article. I look forward to hearing from you!]]>