Quality is still a concern for businesses that are considering deploying voice over IP (VoIP), experts at CeBIT agreed. But vendors said they're addressing the issue and their efforts combined with another development -- the wide acceptance of Session Initiation Protocol as a standard -- are helping to drive VoIP use in both the business and consumer markets.
Performance management tool developer Fluke Networks Inc. and system integrator Cats & Dogs BVBA both stressed network assessment and monitoring as keys to ensuring quality VoIP services. Both companies suggest that businesses monitor their existing networks before implementing VoIP to make sure that the network can support it.
To identify weaknesses in his customers' networks that could affect voice quality, Bart Wolfs, commercial director at Cats & Dogs, installs monitoring equipment over a 10-day period. After customers have made any network upgrades that he recommends, he runs the test again to be sure the changes improved network performance.
Too much demand for VoIP service can also cause difficulties, said Michael Gingele, network system engineer at Fluke.
"The challenge in deployment is, it works for 100 people, but the problems start when you add more," he said.
Fluke's monitoring tools are useful as companies expand their VoIP networks, he said. They allow enterprises to monitor VoIP performance from the user terminal to the call server. The tools also help ensure that the VoIP service doesn't detract from the quality of other mission-critical applications that share the network, he said.
Better quality measurement and quality assurance are making VoIP more attractive to users, but technology standardization is also proving an attraction, especially the adoption of SIP as a standard, said Wolfs.
"With a closed system, you're always in a trap with licensing from a vendor," he said.
For example, customers with proprietary VoIP systems may have been unable to add services like interactive voice response, because of the expense of adding the service from a proprietary vendor. With SIP and other open standards, adding and integrating services is less expensive, he said.
Frank Lange, an Avaya Inc. spokesman, agreed. "With SIP, now vendor B can communicate with vendor A, so you can integrate voice into other applications," he said.
AVM GmbH, a supplier of mainly consumer VoIP products in Berlin, said the acceptance of SIP has also helped grow the consumer VoIP market. SIP enables products from different vendors to interoperate, which helps grow the market, the company said.
Still, London-based Skype Technologies SA, which uses proprietary technology, may continue to make inroads, as a few exhibitors at CeBIT showed off Skype-certified phones.
Netgear Inc. displayed a Wi-Fi phone that comes loaded with Skype software. The phone was introduced earlier this year and will become available in June.
Topcom NV displayed a Skype-certified cordless phone that lets users make and receive VoIP calls, make and receive regular telephone calls and text-chat through Skype. The phone isn't yet for sale.
Ascalade Communications Inc. also showed off a Skype-certified cordless VoIP phone.