The program, dubbed Callternatives, will begin in five U.S. cities, and customers will be able to call throughout the United States as well as other countries including India, Japan, Mexico, South Korea, and Taiwan.
Sprint announced the program last month, but did not give any specifics.
Phone companies, many of which own IP backbones, are increasingly experimenting with off-loading their voice calls from the telephone network onto the Internet, where many calls--especially those that cross international boundaries--can be routed more cheaply.
Today, for instance, Excite signed a two-year agreement with Net2Phone to bring Internet telephony to Excite customers in the United Kingdom, Germany, France, Australia, the Netherlands, Japan, and Sweden.
While IP phone calls can often cost less, they also can result in lower quality. But phone companies have little choice but to enter the market with a vengeance, faced with stiff competition from Internet companies trying to take advantage of the new medium.
Along with keeping up with potential competition, using the IP network will eventually allow companies to provide "enhanced services" such as "unified messaging," in which a user can pick up messages either over the computer or the phone or use a singular connection for both data and voice, said Sprint spokeswoman Robin Carlson.
Sprint has not set firm prices for calls; that is something it still is experimenting with in the trials. But during the trial, customers can save mostly on international calls. The per-minute cost for calls is 7.5 cents in the United States; 67 cents to India; 29 cents to Japan; 35 cents to Mexico City; 30 cents to South Korea, and 37 cents to Taiwan.
Participating cities are as follows: Atlanta, Dallas, Los Angeles, San Francisco, and Seattle. One need not be a Sprint customer to participate, Carlson said, but Sprint customers can participate by being prebilled to their credit cards for blocks of service in increments of $10 and $25.
Customers call into a local access number, which then routes calls over Sprint's IP network and out to a local gateway on the other end.
Calls are "packetized" on the front end so they can travel like other Internet data and then they are "depacketized" and transformed back into voice on the other end. The process can result in slight delays, echoes, and call fuzziness--but Carlson said the general quality is acceptable to most users.