Weigh the pros and cons of using VoIP on mobile devices

As VoIP's popularity continues to grow, its next target market could soon be cell phone users. How soon will you be ditching your mobile phone provider? Deb Shinder takes a look at how using VoIP over mobile devices works and discusses whether it's really a viable option.

Many individuals and businesses are already enjoying tremendous cost savings by replacing or supplementing their traditional PSTN landlines with VoIP services. For my small business, I have both a basic phone line (used for faxes and the security alarm system) and a low-cost VoIP line from Lingo.

The landline's total monthly charges come to $42.12, and it doesn't have any extra features such as voice mail. Making long-distance calls outside my local area code costs extra. My VoIP line costs $25.10 per month, and it includes voice mail (which I can forward to my e-mail inbox), call waiting, three-way calling, speed dial, and unlimited long-distance calls to anywhere in the United States, Canada, Puerto Rico, and 21 other countries, including Western Europe, Australia, New Zealand, Singapore, and South Korea.

Because you can get so much more for so much less, it's surprising that more people aren't ditching their landlines for VoIP. In fact, I'll probably be turning off AT&T altogether when my current security monitoring contract is up this November.

Of course, there are trade-offs. Although call quality for almost all VoIP calls is as good as the PSTN, there are rare occasions when it's not. And there's the fact that VoIP won't work if the Internet is down or the electricity is off. But for those times, we have our mobile phones for backup.

Now, though, it looks as if VoIP is poised to threaten the mobile phone providers in the same way it's threatening the future of the PSTN. VoIP over mobile devices is set to be the next big thing in the industry. Let's take a look at how that works—and whether it's really a viable option.

VoIP over Wi-Fi

Many of the PDAs/handheld computers available today have built-in support for 802.11 wireless networking (Wi-Fi), and more and more Wi-Fi hotspots are popping up all over the country and world. Wireless connections are available at many airports, hotels, coffee shops, and other public gathering venues. Some cities have even undertaken initiatives to provide Wi-Fi coverage for the entire city, either for a monthly or daily fee or "free" (that is, at taxpayers' expense).

With VoIP software such as Skype's mobile version installed on a handheld device, users can connect to a wireless network and make VoIP calls at no extra cost (to other Skype users) or for a fee much smaller than the typical cell phone bill. Let's look at the numbers.

With the major mobile carriers, the cheapest monthly cellular plans in my area range from $29.95 to $39.95, which includes 300 to 600 minutes of talk time. Skype's SkypeOut plan, which allows you to make unlimited VoIP calls to regular landlines in the United States and Canada, costs $14.95 per year. If you want others to be able to call you from regular phones, you can add the SkypeIn service (which comes with free voice mail) for $36 per year.

That's a total of about $50 per year—or $4.25 per month. There's quite a difference between that and the cost of a cell phone.

Of course, with this setup, you're dependent on Wi-Fi coverage. So if you're in an area where no wireless network is available, you have no phone service. For those who stay within urban areas with widespread Wi-Fi availability, this is feasible. For those who must travel to smaller towns or rural areas, not having phone service in those locations may be unacceptable.

However, even if mobile VoIP can't replace your cell phone service, you might be able to use it to lower those cell phone bills.

VoIP over mobile providers' broadband networks

If you already subscribe to broadband Internet service on your cell phone (for example, Verizon's EVDO), and you also make a lot of phone calls, you may be able to save money by scaling back your calling plan to the minimum and using Skype or another VoIP service over your cell phone's broadband connection. Here's how that works:

I subscribe to Verizon's unlimited Internet access plan on my Pocket PC phone (a Samsung SCH-i730 running Windows Mobile 2003). This gives me access to my Exchange e-mail, the Web, and other Internet applications for Windows Mobile. I've also installed Skype for Mobile on the device, and I can connect to the EVDO network and use my Skype account to make phone calls during the business day that don't get charged against my allocated anytime minutes.

Since unlimited data access costs $59.95 per month, it doesn't make sense to subscribe just to use VoIP, but if you need the unlimited Internet access anyway, using VoIP might help you save $20 or more on your cell phone service by getting a plan with fewer minutes.

VoIP over a cellular connection

With a third-party application called iSkoot that you can download for free, you can make Skype calls over 3G/GPRS and GSM/CDMA cellular networks. The company says its goal is to make VoIP calling available over all networks and all mobile devices; however, at the present time, it only supports certain phone models.

Although you still need a data plan from your Internet provider, you don't need a costly unlimited high-speed service. In this case, you do incur charges for the standard airtime rates for your mobile phone calls. The iSkoot service is available worldwide.

The WiMax Promise

Worldwide Interoperability for Microwave Access (WiMax) is a new long-range wireless technology expected to greatly increase availability of wireless connectivity. In theory, it can provide communications over 70 miles; in practice, implementations will be able to provide a relatively high-speed connection (for instance, 10-Mbps) over one to 10 miles—still a much greater range than the typical 802.11 Wi-Fi network, which extends to about 300 feet outdoors.

If and when such wireless service becomes truly ubiquitous, mobile VoIP may truly come into its own. Meanwhile, it can definitely be a useful option in certain situations, but it probably won't do away with your need for a cell phone for the immediate future.

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Deb Shinder is a technology consultant, trainer, and writer who has authored a number of books on computer operating systems, networking, and security. She currently specializes in security issues and Microsoft products, and she has received Microsoft's Most Valuable Professional (MVP) status in Windows Server Security.

About Deb Shinder

Debra Littlejohn Shinder, MCSE, MVP is a technology consultant, trainer, and writer who has authored a number of books on computer operating systems, networking, and security. Deb is a tech editor, developmental editor, and contributor to over 20 add...

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