The speed of frame relay links was a concern for premium movie channel provider Starz Entertainment Group LLC when it was planning a VOIP rollout. "We were going to try to do a VOIP rollout with a WAN infrastructure not quite big enough," said Gary Pfeiffer, vice president of IT for Starz, in Englewood, Colo. Beyond detecting such issues, a predeployment assessment establishes a base line for existing calling patterns to help in guiding the design of a VOIP system, according to IPCs Wright, whose company resells ShoreTel VOIP equipment.Network providers are fighting the FCC on VOIP wiretapping Click here to read more. For small and midsize enterprises, a predeployment assessment can transcend just looking at whether the network can carry voice calls. "What people are not thinking about are issues like, Do you have any change management processes in place? Do you have uninterruptible power supplies in your phone closets? Do you [track problems in] a trouble report?" said Grant Vogelsang, senior customer systems analyst at SaskTel, in Regina, Saskatchewan. SaskTel, in its full network assessments, looks at environmental elements that can affect a VOIP deployment. "We look at all their [wiring] closets, cabling structure, patch panels. Most people dont even know what is hanging off which port," Vogelsang said. "People talk about five nines [reliability] but dont know whats required for it in terms of organizational structure." Beyond solving the kinds of problems that such assessments turn up, another critical success factor for VOIP implementations is the use of QOS (quality of service) prioritization to ensure that latency-sensitive voice traffic gets priority when applications contend for limited bandwidth. Some resellers might be tempted to take a shortcut to QOS by recommending a boost in performance, believing that contention wont take place on a fast LAN. "When [bandwidth contention] does happenand it always doesthe users network isnt provisioned to prioritize voice over data," said Gregg Jankowski, IP communications practice manager at Cisco reseller Analysts International Corp., in Auburn Hills, Mich. "From a resellers perspective, its a shortcut that can be taken that saves on engineering services hours and makes it a [more] profitable deal." Jankowski said he believes its critical to ensure that QOS provisioning is consistent between the customers network and the carriers implementation of QOS, which is called Multiprotocol Label Switching, or MPLS. "The critical component is making MPLS work properly between the customers distributed facilities. People dont thoroughly investigate and work with carriers to make sure QOS stays consistent and true throughout the WAN," Jankowski said. Within the customers own network, a preassessment can also look for QOS capabilities within switches and routers and ensure that those functions are "turned on in every component on the network," said Richard McLeod, director of IP communication solutions for worldwide channels at Cisco, in Atlanta. Predeployment assessments can go a long way toward ensuring the success of a VOIP implementation, but its also important to continue to monitor the network to ensure that it stays up to par. Because change is constant in a network, performance problems can be introduced without detection until users start complaining about call quality. "The key is that network assessment is not a one-time thing," McLeod said. "Ongoing checking and monitoring the health of the network is an important value add the VAR always brings to the customer." Check out eWEEK.coms for the latest news, views and analysis on voice over IP and telephony.
One surprise that emerged from such an assessment at Starz was the discovery of much unnecessary traffic on the network, according to Pfeiffer.