Internet telephony ? converting analog voice signals into IP network traffic, and then transferring it over the Internet ? has attracted considerable attention, primarily because of the potential it offers for saving money.
According to USA Global Link, its Internetwork telephone service will save some 80 to 90 per cent over the regular cost of international telephone calls. And rival Vienna Systems claims it?s sometimes possible for corporations to eliminate telephone charges altogether with its Vienna.way gateway product. However, most people?s experience of Internet telephony will have been with PC software and dial-up lines ? a combination that doesn?t always work well.
According to Kent Elliott, president of Vienna Systems: ?The problem is that you cannot guarantee quality. Sometimes you can get good quality over the Internet; sometimes you can get good quality but with a 900ms delay; and sometimes you get useless quality.?
Sam Sethi, Netscape?s UK product manager, agrees: ?The problems at the moment are reliability and availability: can I guarantee that I can click on a button and get the person I want? If not, the telephone is always going to be preferable.?
Nevertheless, many people are successfully using Internet telephony products, such as Microsoft?s Netmeeting. According to Martin Gregory, Internet platforms product manager at Microsoft: ?End-users are using Netmeeting to communicate with relatives across the world. Each party only pays for a local phone call to their Internet dial-in point, and there are many people using it on a regular basis now for international calls.?
Previously, both parties would have required the same Internet telephony software on their PCs, since proprietary protocols were used. Now, the widespread adoption of new standards means that an increasing degree of intercommunication between different software products is possible.
Such a solution, while it may save money, is probably not appropriate for serious business use. But, USA Global Link?s Internetwork should be a different story. According to Mark Petrick, the company?s corporate relations liaison manager: ?It is a telephony service ? it was developed by telephone engineers, and has been built to telephony standards. We?re a telephone company, and it will appear to the user just like a conventional telephone service ? it will be significantly different from the computer-to-computer telephone solutions.?
To build Internetwork, USA Global Link is investing some $500m in a network of more than 1,000 gateways that are being placed in various cities around the world. Global Exchange Carrier (GXC) is building a similar network, known as G-Cubed, and has signed up 11 Internet Service Providers who will install Vienna.way equipment. Users will connect to these exchanges by means of an ordinary telephone, over the local telephone lines. Thereafter, the analog telephone call is converted to a digital signal and routed over the Internet to a similar exchange in the destination city. The signal is then converted back to analog, and passed over local PSTN lines to the called party.
A question of quality
Petrick is confident that any problems involving quality have been overcome. ?To us, the Internet is just another routing strategy. We have a hybrid solution that uses unique compression algorithms and unique routing solutions. We feel that there will be virtually no delay, and we will work around congestion in the public Internet backbone.?
However, according to Elliott, the potential of Internet telephony ? or more correctly, IP telephony ? is perhaps much greater in an environment that is protected from the vagaries of the public Internet. ?In a corporate network we can control the bandwidth available and the number of routers, so we are far more likely to get consistently high quality.?
Setting the standard
There is a standard being worked on ? RSVP (Reservation Protocol) ? that addresses the problem of datastreams over an IP network. Otherwise, someone else in the office could suddenly decide to send a big file, and completely trash the bandwidth for telephony traffic.
Vienna?s Vienna.way Server is intended for corporations, major carriers and ISPs which own bandwidth, and thus have the potential for a more disciplined network than the Internet itself. The gateway can convert your analog telephone traffic to IP, and route it over digital circuits. It offers the facilities that you would expect from a telephone switch ? conference calls, call hold, call forwarding and so on. It also interfaces with PCs using telephony software compatible with the new H.323 standard ? so you can place calls between any combination of PC and telephone user.
?With a product like Vienna.way, you can achieve greater utilisation of corporate bandwidth,? says Elliott. ?Currently, many organisations would have both analog and digital bandwidth between their various sites, but the bandwidth sharing would be hard coded. During the day there will be lots of voice traffic, and during the night lots of data.?
In these circumstances, part of the bandwidth would be wasted at certain times. ?By placing a Vienna.way Server behind the PBX, all traffic becomes IP data, and you no longer need circuit-switched voice,? adds Elliott.
Another barrier to PC telephony products is the user interface ? usually, speakers and a microphone. ?It?s not an instinctive choice to pick up a microphone on your PC; it?s easier to pick up your phone and get on with it,? says Sethi. This hurdle can be overcome: special adaptors allow you to connect an ordinary telephone to a PC. When the handset is lifted, the PC sound card is removed from the circuit, usually resulting in much better quality.
But IP telephony is poised to deliver far more than cheaper telephone calls. Sarah Skinner, telecoms analyst at Datapro Information Services, believes the future lies in voice communication. ?Combining voice into other products is where IP telephony is going to be valuable in the business market,? she says. ?The biggest uses will be in sharing documents while speaking to people, and applications in call centres and perhaps Web sites.?
Users with a problem might first consult a vendor?s Web site, and if they needed further assistance they could click on something that would let them talk directly to support personnel. Ultimately, PC telephony applications have the potential to make far-reaching changes to the way we do business, believes Elliott. ?Combining voice and data changes our ability to respond to people.?
This capability is provided by PC products that combine several types of data ? voice, video, whiteboarding and application sharing (whereby both parties can see the same document and work on it together). There are many processes in business that could happen a lot quicker with products like this. ?Imagine two lawyers working on a contract,? says Elliott. ?With application sharing, both of them could see the contract on-screen. If one doesn?t like something, he can just type in the clause he wants and discuss it there and then, instead of having to print it out, fax it, and make a separate telephone call later.?
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