Security should be the first consideration for any IT department about to implement voice over IP on a local-area network, an executive with an equipment manufacturer says."When you're talking to your provider, ask them 'How am I going to protect myself from someone hacking in and listening to senior executives talking on the phone?'" said Steven Fair, executive vice-president with Phybridge Inc., based near Toronto, Canada.Fair, who spoke to an audience of 12 during the IT360 conference in Toronto, was acting president of Avaya Canada Inc. before starting his company this year. When Avaya would install IP telephony, it usually took 18 months to complete the project because it required new cabling and they had to figure out how to plug the holes hackers could use to eavesdrop. He noted there are lots of hacking tools users could download from the Internet."If you're putting voice on to LAN, security is No. 1."Other issues include the cost and prioritizing voice packets over data.Phybridge plans to launch May 1 its UniPhyer hardware, which is designed to set up a parallel voice network using existing twisted pair copper cabling and RJ-11 jacks. Users can install RJ-11 to RJ-45 adapters on their IP phones, and the UniPhyer connects the old phone network with the data network.Fair said users should ask vendors whether they have the ability to handle quality of service and whether they can put power over Ethernet on their LAN switches.Another consideration is the fact that data networking experts are not always well versed in voice."Consider someone who's a lead who understands telephony," Fair said. "If you don't have somebody maybe have a look outside for someone who is the project manager."But installing IP telephony can help companies save money by having fewer people and devices to manage, said Matthias Machowinski, directing analyst for enterprise voice and data at Campbell, Calif.-based Infonetics Inc.Machowinski, who did not attend IT 360, made his comments during a telephone interview from his own office using a soft phone. Though some static could be heard in the call, it was hard to distinguish it from a PSTN call and Machowinski said earlier problems with VoIP have been dealt with by traffic prioritization.Companies often had to buy new network equipment to support voice traffic and this was a boon to manufacturers such as Cisco Systems Inc., Fair said."Companies ended up having to upgrade LAN switches and then cabling," he said. "Many people didn't realize initially there were these costs."With the combination of voice and data on to one network, it's more difficult to find the cause of problems, Fair said."In the old days it was a phone, a wire and a (private branch exchange)," Fair said. "Troubleshooting was easy. Today you have a router, LAN switch, cabling, and IP phone."Machowinski described VoIP connections as " a bunch of best effort types of links," not all of which are controlled by a provider.Fair said companies changing from TDM to VoIP "were looking for cost savings originally" but did many did not end up saving money because long-distance rates, in some cases, have dropped to three cents per minutes."If you can move from the TDM world to the IP telephony world cost-neutrally you have done a good job."Users installing the technology need to be aware of the capabilities of their data networks, including virtual local-area networks (VLANs), which versions of routers and switches they have, firewalls, DHCP and TFTP servers, network address translation (NAT), multicasting capability and encryption techniques.He also advises users to make sure their wide-area network has redundant connections from more than one service provider.