THE leafy Ivy League campus at Dartmouth College in New Hampshire may not have the look and feel of a technology testbed. But looks can be deceptive.
Almost 20 years ago, Dartmouth was one of the first places to wholeheartedly embrace electronic mail, rolling out a simple system called BlitzMail across a primitive university-wide network. Then in 2001, Dartmouth unveiled a campus-wide wireless network that allowed students and staff to surf the net and to access email without the hassle of wires and plugs. Once again, Dartmouth was ahead of the game: similar Wi-Fi hotspots have now sprung up in coffee shops, restaurants and airports all over the world.
Dartmouth鈥檚 latest plan is wireless internet telephony. From last week, any student equipped with a headset, a laptop and some software from the networking company Cisco has been able to phone from anywhere on campus to anywhere in the world via a wireless link to the internet. Voice calls to US destinations are free: the university says the internet calls are 鈥渢oo cheap to meter鈥�, so it just isn鈥檛 bothering. If Dartmouth鈥檚 track record is anything to go by, we will all be making free telephone calls over wireless internet links in future.
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Internet telephony is the kind of technology that can creep in and become the norm before anyone has even noticed.
An ordinary telephone call creates a direct link between one telephone and another, with a telecoms company providing the transmission route. This is a rather inefficient way of using a network, since wires tied up for voice calls cannot be used for anything else.
Internet phone calls don鈥檛 need a dedicated connection. Instead, the conversation is carried in a sequence of data packets 鈥� fixed-length parcels of speech data that include the source and destination addresses 鈥� which are then routed across the internet like email. At the receiving end, the data in the packets is reassembled into audible speech. This allows voice data to share comms links with all kinds of other internet data, like web pages and email, and avoids the waste of bandwidth that comes when a dedicated circuit has to be set aside for each call (see Graph).
Doing away with a separate voice network allows telecoms companies, and even relatively small networks like Dartmouth鈥檚, to slash costs. Because calls need to be made to people on their standard phones, calls leaving Dartmouth鈥檚 network have to be routed via a gateway onto the standard phone network 鈥� and while using this is cheap for calls inside the US, international calls are costly. Dartmouth says that monitoring calls and sending out bills would cost far more than the calls themselves, so students only get charged for the much more expensive international calls. Many telecoms companies have already moved over to packet-switched internet transmission in parts of their networks. The chances are you have already made a call over the internet without even knowing it.
The technology could disrupt the economics of telecoms. Since internet calls are routed like emails, they can be paid for in the same way. So beyond the cost of running a computer and keeping a connection to the internet, they are free, just as at Dartmouth. If this kind of internet telephony takes off, phone companies could find their business vanishing.
And with wireless data links becoming common, the same thing could happen to cellphone networks. At Dartmouth, the college鈥檚 wireless network is open to anyone within range, so people living near the campus or passing through can have access. There is nothing to stop them making free wireless internet calls, either, says David Kotz, a Dartmouth computer scientist who plans to study how people use the new wireless system.
So is it time to cancel that costly account with the phone company? Perhaps not just yet, unless you don鈥檛 mind your phone calls sounding as if they taking place under water. A couple of years ago, setting up a call over the internet was about as easy as making ham radio contact with Alaska. Call quality is better today but still variable. Kotz promises that on the Dartmouth campus the quality will be good, because the network has the capacity to handle net calls. 鈥淏ut out there on the internet, you are competing with all the other traffic,鈥� he says. That鈥檚 when call quality can suffer. So given the choice, you might prefer to stick with your telecoms company. Either that, or move to Dartmouth.
Will wiretappers bug internet calls?
A decade ago, law enforcement agencies began to worry that the then new technology of digital telephony could provide a haven for criminal activity because it was difficult to wiretap. After much lobbying, the US passed the 1994 Communications Assistance for Law Enforcement Act, which requires telecommunications companies to make their digital telephone lines wiretap-friendly.
The FBI is now gripped by a similar fear about internet telephony. It is by no means clear that phone calls over the internet are covered by the 1994 law, and the law enforcers fear they may soon find themselves locked out from an increasing number of calls.
The issue was brought out into the open this year by Jeff Pulver, founder of Free World Dialup, an internet telephony service which claims over 60,000 users around the world. He asked the US Federal Communications Commission (FCC) to rule on whether Free World Dialup should be considered a telecommunications service or not. If not, Pulver avoids what he sees as excessive regulation by the FCC and his callers avoid the unwanted attentions of the FBI. Look out for a ruling before the end of the year.
