IP CONVERGENCE HAS been vaunted as one of the most profound developments in modern communications. The use of internet protocol technology to bring voice, data and video traffic together over one network - embracing as it eventually will the international phone system, company local area networks, wide area enterprise networks and the internet - is expected to have far- eaching implications for the way people and businesses communicate. Enterprises are taking their first steps towards this eventuality through IP telephony, adapting their local area networks to carry voice traffic. Toll-free dialling For companies with heavy telephone and data traffic to overseas offices or factories, a merged IP network represents an opportunity to cut costs significantly. By putting voice traffic over the data network, companies can circumvent traditional phone lines and dial IDD toll free. IP communication between a Hong Kong company and an overseas factory can be implemented in three ways, says Gartner Research vice-president Andrew Chetham. 'Leased lines are available and if you have an IT department you can put any kind of service over it ... But leased lines are point-to-point connections, so they are less popular now than IP virtual private networks from telecoms [carriers], which can link several offices with guaranteed bandwidth.' The third approach is an ordinary broadband internet service, which should have enough bandwidth to handle the cross-border voice traffic of small businesses. 'The idea that you need very high standards for voice is a bit out of date. Video is a different matter, though, and it is more vulnerable to internet congestion. Nevertheless, I know of at least one large American group that puts everything on the internet and it seems to work all right,' Mr Chetham says. Walter Fung, director of business development and strategic planning at NNT Com Asia, a global infrastructure provider, says there are many software solutions available for voice-over-IP on the internet that may be suitable for small business, but there are no guarantees of quality. 'In some locations - such as Hong Kong, Singapore, Tokyo or Taiwan - the internet is well developed and the voice quality may be okay. In other places, such as [mainland] China, where multiple carriers are interconnected, there may be a lot of congestion, therefore voice and video quality will suffer a lot,' Mr Fung says. However, only large enterprises can obtain good value from leased lines. Mr Fung says: 'Traditional leased lines enable users to build a dedicated network for any service, including IP and traditional PBX phone services. The finance sector uses leased lines to obtain high security and good voice quality, and some banks have networks as big as a medium-sized carrier, but this is an expensive option.' One for the road One of the more significant differences that IP convergence is making to businesses is in enabling mobile workers to stay in touch with their headquarters. David Chung, Cyberport's senior manager, information technology operations, says: 'When I travel, I use a laptop with a soft phone [or software telephone application] to connect to Cyberport through the internet and it saves the cost of international calls.' Norman Bo, Nortel Hong Kong product marketing manager, enterprise solutions, says IP telephony makes it easier for staff travelling on business to stay in touch. 'On a converged network, mobile employees with a laptop or PDA equipped with a soft phone application can easily make a connection to the corporate network through the internet using a hotel wall jack or a wireless hot spot.' He says that the connection will be secure because it is protected by a virtual private network on a corporate server, and the voice or data traffic being transmitted will be encrypted. Cyberport's Mr Chung says instant messaging can be another productivity aid on a soft phone. Instant messaging on IP networks assists staff collaboration. 'With instant messaging, you know your colleagues are at their desk and you can get a response fast - I do it all the time. My subordinates can use mobile phones but their number may be engaged. With IM, I can stay in touch with them and, incidentally, see the time they log on to work in the morning.' What are the costs? The only catch is that, unlike conventional data traffic, a delay of even a fraction of a second in voice traffic can degrade the quality of a telephone conversation. So, voice traffic has to be recognised and given priority on the network. This can be done by networking equipment such as routers and network switches, using a quality of service (QoS) function. Older network devices may not have QoS built in, so companies wishing to merge their voice traffic with data must check if their equipment needs to be upgraded or replaced. IP telephony can use the same wired infrastructure as the existing data network. 'Cat 6 cable will give you up to 1 gigabit per second, and optical fibre provides 1 Gbps or even 10 Gbps for organisations with a lot of traffic, especially video-conferencing,' Mr Chung says. Nortel's Norman Bo says: 'For those companies able to retain their network infrastructure, the biggest cost in changing to IP telephony could be buying the IP phones, which have larger LCD screens and more functions than conventional TDM [time division multiplex] phones.' Juniper Networks enterprise marketing director, Asia-Pacific, Andrew Ma says: 'Right now, we are moving from the early adopters to the first stages of mass deployment, so prices are falling and there is a greater choice of vendors.' Go slow or go fast Some businesses build a converged network in one step rather than gradually migrating over and ending up with two networks - the conventional network and phone equipment and the new unified IP network that does the same job. Mr Chung says: 'For small firms with 30 to 100 people, it is possible to install a converged IP network in one operation.' Mr Ma strikes a note of caution, however. 'A small network could be put up 'quick and dirty' in one or two days, but it is not worth jeopardising reliability and security for speed or marginal cost saving,' he says. An alternative approach to network converging is Wi-fi-based telephony, supported by transceivers fitted around the premises. This may cost 30 per cent to 40 per cent more than a wired system, but there are significant business advantages. Nortel's Mr Bo says: 'Most companies miss a lot of business calls because employees are walking around the office unavailable to take calls. A wireless system can enable contact staff to be available for virtually the whole working day, with positive benefits in productivity.' Mr Chung says for colleges and other organisations that need to give users network access on a large campus, wireless can lower infrastructure costs. 'Wi-fi can provide many local access points, while WiMAX can provide better coverage with even less infrastructure.' More on bandwidth Many IP phones have large LCD screens so video telephony between two people, or video-conferencing with multiple participants, is straightforward. Mr Bo says: 'Old-style video-conferencing, using the H.323 [video compression] was expensive and limited, but the new SIP standard enables additional features, including online collaboration with multimedia applications. 'The bandwidth needed for IP telephony now is about 150 kilobits per second for voice and 300 kbps for video. In a medium-sized Hong Kong company the bandwidth required for inter-office communications, plus the mobile staff phoning in through the internet, would probably not exceed a typical 5 megabits per second broadband internet service.' Cyberport's Mr Chung agrees that a broadband internet service can sustain voice quality. 'We recently held an IP video-conference with Canadian partners with 50 people in the conference room and we could see each other on 100-inch screens. The voice and image quality were at an excellent level during the two-hour session.' Although the internet is the cheapest route for IP telephony, many firms will pay more to lease an IP line with end-to-end QoS, thus protecting the quality of their voice communications. Nortel's Mr Bo says: 'Lines may be classified as gold, silver or bronze according to QoS and bandwidth service guarantees. Faxes do not transmit well over the Net so users must ask for the T.38 standard, which indicates that the line supports faxes like a conventional phone line.' Security issues In a converged network, voice equipment, which has had little security provision, is regarded as a weak link. To protect a converged network against intrusion requires a voice-enabled firewall - most existing firewalls can be upgraded. Juniper's Mr Ma says for call centres, or in critical businesses such as finance, a voice-enabled intrusion detection and prevention system is also needed. 'A piece of free software called Vomit can be downloaded from the internet to sniff your network traffic and reconstruct your phone conversations. I talked to a Japanese IT manager with VoIP, who found his phone bills were high, with masses of calls logged to the Middle East. Someone had hacked the PBX and was using the network for toll fraud.'