GTE launch carrier-class VoIP service

1999-10-12

Telecomm 99 in Geneva this week saw the launch of a Voice over IP service from GTE Internetworking, aimed at telcos, ISPs and Internet Telephony companies. The question is, will they bite?

Voice over IP has long (in Internet time) been a possibility but has always been hampered by theoretical (and practical) issues of reliability. Essentially, this is to do with moving from a circuit-switched network (where devices link together to provide a guaranteed bandwidth path from end to end) to a packet-switched network which divides information into chunks, which are routed across the network and reconstituted at the other end. This, latter technique, used by the Internet Protocol, offers few guarantees about latency (the time the packet takes to arrive) or reliability (whether the packet gets there or not) in the network itself, with mechanisms being implemented in the devices at each end to, for example, acknowledge receipt of a packet. For telephone users this lack of guarantee equates to the possibility of pauses in conversation and drop-outs where parts of the conversation are lost. Those are the downsides, but on the upside we have the huge potential of cost savings to telephone user and telco alike, as the cost of sending information over the Internet is greatly reduced compared to traditional leased lines.

So, will the telcos bite? The two reasons why they won’t are fears about the reliability issues and the overheads of moving services to a new supplier. In order to guarantee a high level of service, GTE are implementing a IP network dedicated specifically to the service, plus a technique coined “Intelligent Route Diversity”. This refers to a number of services including load balancing, dynamic routing and failover to the (circuit switched) PSTN should the reliability falter. In other words, GTE Internetworking have covered their bases. They are not routing packets over the Internet but dedicating Internet technology to provide bandwidth channels over which they have more control. Brian Walsh, of GTE Internetworking, told us that the company was achieving sub-100 millisecond one way latencies, well below the 200 millisecond target agreed to be “undetectable to the human ear”. This should appease the service providers: if not, they have the additional guarantee of re-routing traffic to the more conventional PSTN.

GTE Internetworking are likely to emphasise the cost reductions that telcos can achieve employing IP-based bandwidth for voice calls. Walsh noted that companies could expect savings of up to 25% off charges within the US, with greater savings possible on international services. It may be that, with PSTN competition already cutting prices to the bone, many companies find they have little choice but to quell their fears and head for VoIP.

(First published 12 October 1999)