Cheap calls wooed the early adopters, but with a bit of hard work, presence and collaboration services can cement the marriage of voice and data networks. John Kavanagh reports
The romance began with Skype wooing consumers with free phone calls through their home PCs. It blossomed as companies took voice over IP to their hearts, enticed by the prospect of free phone calls across their existing data networks.
But companies are now finding they have to work hard at the maturing relationship to enjoy the wider benefits of IP telephony and to overcome issues ignored in the initial excitement.
"Cost savings are still a primary decision factor but companies are looking more rigorously at the overall business case," says Gartner analyst Katja Ruud. "The collaborative potential of VoIP now gets included, especially in the light of new multimedia IP services.
"There are so many options now: you can leverage your existing network and manage VoIP yourself, use your own network but let someone else manage it, or use a hosted service or one of various other managed service offerings. We spend a lot of time discussing with users how to mix and match the alternatives."
VoIP certainly looks inevitable. User surveys put the number of organisations in the UK using IP telephony seriously at between 25% and 40% - with an expected increase to 85% to 90% in the next two years.
Indeed, voice services are by far the main reason behind organisations moving towards converged IP networks, according to the latest annual survey by the Communications Management Association (CMA).
It found that 60% of managers cited VoIP as the primary reason for network convergence. In a separate question, 73% said VoIP was a key element of their collaboration strategy - up from 63% last year.
Cost savings come in various ways. For example, calls between scattered offices on the IP network are free, and a single voice and data network can be cheaper and easier to manage and expand. Other benefits highlighted by suppliers and users include staff being able to have the same phone number wherever they are and greater flexibility to allow staff to work from home.
Things get more complicated with the less tangible benefits of looking beyond phone calls and adding VoIP to other applications on converged networks.
In particular, unified communications was mentioned by 40% of respondents in the CMA survey as a reason for moving to a converged network - up from 30% the year before.
The significance of the merging of voice and data networks is reflected in Microsoft's interest in this market, not least through the launch of its Office Communications Server 2007 software, the update to Live Communications Server 2005.
"Traditionally, VoIP has meant swapping one cable for another and providing a new phone, with the user seeing little difference, but we see VoIP as part of something much bigger," says Mark Deakin, unified communications manager at Microsoft UK.
"We are certainly seeing increasing interest in VoIP, but different people have different ideas about what it is. For some it is Skype, for others it is about saving money by using an upgraded IP network, but if end-users still have to tap in the extension number on their phone, they are not getting anything new.
They should be able to jump from e-mail into a video phone call with a simple click, using presence services such as Instant Messenger, or click on a contact in Outlook, instead of having to exchange numbers and fix a time."
Presence awareness was identified as a benefit of VoIP systems by 22% of managers in the CMA survey. Better collaboration was mentioned by 35%, and the related issues of web conferencing and workflow were cited by about 18%.
Deakin says, "All this means that it is important to look beyond the savings on phone calls and to look at giving value to users by taking the opportunity to review the entire communications strategy."
Companies certainly need to pay more attention to preparing a proper business case for VoIP, says Charles Davis, chief executive at IP network supplier SAS Group. "Many organisations feel there is no alternative to IP telephony and do not stop to consider whether there is a business case to support it," he says.
Others echo this point. "People recognise that the benefits go beyond call cost savings, but many organisations, especially smaller companies, do not quite know what the extra benefits are or how to measure them," says Ruud.
"Easier collaboration and being able to contact someone quicker: will these save an hour a week? It is hard to make a business case on factors like these, so companies go back to the hard savings and look at these other things as a bonus."
The business case is further complicated because a switch to VoIP often means replacing expensive traditional internal phone exchanges.
"The business justification for implementing IP telephony on a site where there is an existing switch can be difficult," says Nick Leake, director of operations and infrastructure at ITV. The broadcaster introduced VoIP as part of the replacement of the company's entire IT set-up - a project that won a medal in last year's British Computer Society IT Professional Awards.
"You have got to decommission a capital asset and spend more capital on the new equipment," Leake says. "The natural thing is to sweat the existing asset until it dies, which could be many years. So establishing the business case has proved a bit tricky for us.
"It includes not having lots of different maintenance contracts, reduced administration costs, and being able to have a single number plan across all sites.
"At ITV, we switched to VoIP gradually. IP telephones were provided to 1,500 of our 6,000 users initially, with the rest following on. Many of the first batch were at greenfield sites, and it made sense from a wiring point of view to put one set of cabling in. This became a default in all our new sites and sites where we were upgrading local area networks."
Opening a new office or moving to a new headquarters offers one of the best opportunities to move to VoIP. In normal circumstances a gradual migration is suggested by many user companies and suppliers. This might range from temporary or permanent use of an external service to a hybrid approach, with software in a black box enabling a traditional voice switch to provide VoIP features.
Microsoft, for example, works with the likes of Nortel and Mitel in this area, and the Communications and IT Association, which represents suppliers, is testing interoperation between traditional switches and IP networks.
Explaining the need for the tests, the association says, "The take-up of converged solutions was slower than anticipated, mainly because of user concern over product compatibility issues when delivering voice services over data networks."
Experience is pushing other issues to the fore as users realise that moving to VoIP is a major technical project, even without allowing for all the potential changes to the way end-users work.
"Many organisations launch headlong into VoIP without considering the scope of the project, and often with no real knowledge of what is involved," says Davis. "All areas of the project, including local and wide area networks, servers, applications, switches and routers, need to be considered if organisations are to avoid escalating costs and implementation issues, just as in any other major project."
Many suppliers urge prospective VoIP users to conduct a network review. A simple starting point is the fact that one VoIP call typically uses 20kbps if a company does not have the bandwidth to cope with this, call quality will suffer.
More than 70% of managers questioned by the CMA said VoIP quality was a "major concern".
"VoIP is fast revolutionising communications, but many businesses are less than satisfied with the quality of transmission, because they have rushed to install the technology," says Carrie Higbie, network applications manager at network infrastructure supplier Siemon. "They forget that their cabling infrastructure must now support both voice and data.
"VoIP suppliers recommend an infrastructure audit before implementation because the quality of transmission for voice packets is much more demanding than for data packets, and transmission delay, packet loss and jitter must be kept to a minimum.
"Network managers need to ask whether the infrastructure can handle the new VoIP system. Does it meet today's standards? Will the increased traffic slow existing applications and affect business operations?"
Such questions become more pressing if wireless voice networks in offices are being considered. More than 60% of managers questioned by the CMA said wireless VoIP was of significant interest, compared with 55% the year before, but Ruud says the business case is difficult to make.
"There is a big discussion on whether to add voice to the wireless Lan. Companies say that everyone walks around offices using their mobiles, but for VoIP you usually have to upgrade the network. The handsets are quite expensive, and there might be the alternative of negotiating a better deal with your mobile operator."
Security too is coming under scrutiny. This was the only area in the CMA survey where most (53%) VoIP users were not satisfied.
"We have certainly had more queries about security in the past year," says Ruud. "In particular, as commercial service offerings increase, there are concerns about whether users in one company are sharing a backbone network with others."
So the honeymoon is over. VoIP and its users have moved from romance to the realities of marriage. Whatever the trials and tribulations, the joys mean that this marriage is unlikely to end in divorce.
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