Is VoIP for me?
Since the media hype engine for VoIP is turned up pretty high, I'm not going to spend any time repeating the pitches that you probably know by heart for considering VoIP. Instead, I'll give you a few reasons below for not using VoIP.
Not the only way to lower long distance costs
Since long distance telephone service is available in so many other ways for very little money, if saving money on your long distance bills is your only justification for using VoIP, you may want to reconsider. I use a 3.5 cents / minute AT&T card from Sam's Club that suits my usage just fine and don't have to worry about lugging a VoIP adapter with me on business trips. Most cell phone plans bundle in more nationwide minutes that you can eat in a month, too.
Of course the tipping point in this equation is constantly changing, with the going monthly rate for an all-you-can-eat US and Canada plan from Vonage and AT&T at $25 as I write this in October 2004. If you do a lot of international calling, be sure to check your prospective providers' rates because these calls may not be included in the basic monthly rate.
911 service gotchas
Whether or how well 911 emergency services work depends mostly on your VoIP service provider. So be sure you understand whether 911 services will work and whether there is an extra charge for them before you sign up. (This LightReading story has more details.) Note also that since your VoIP service depends on both power and Internet working it might not be available when you need it.
One thing that used to be true about POTS (Plain Old Telephone Service) phones, is that they worked when the power went out. Of course, since most of us now use cordless phones that need to be plugged in, this advantage has vanished unless you keep a batteryless phone around for use during power blackouts or have your phone on a UPS. But VoIP phones not only need your electric company to be on the job, but your broadband service, too. And getting both these to be 24 / 7 / 365 reliable may be more than your local companies are capable of.
Variable Voice Quality
This is another criteria that has changed over time since entire generations have grown up enduring the generally crappy (yes, that is a technical term) voice quality foisted on us by cell service providers. It's a hopeful sign that users have not had their voice quality expectations lowered by VoIP companies...not yet at least... and expect the same quality as they've had on their POTS phones. Whether you get good quality depends on many network performance factors, some of which you can control (on your LAN) and many that you cannot (at your ISP and on the Internet).
Too many cooks
There are more companies involved in providing VoIP service than POTS and anyone who has wrestled with DSL problems knows the joy of being bounced from company to company when problems arise. If it's important to you to get phone service problems resolved quickly, or you have had less than excellent experience dealing with your broadband's tech support folks, then better pass on VoIP.
- Wrong number
Any ITSP that offers service connecting to PSTN phones will offer you a choice of phone numbers in various area codes. You might not, however, be able to get a number in your local calling area. So it's possible that people calling you even from next door might have to pay for a long-distance call. Note also that your number won't appear in local phone books (which isn't necessarily a negative).