Network preparation and network management are where the biggest problems seem to be occurring. Since the VoIP systems themselves are performing better, it is the integration with the network where problems are occurring. What new stresses does VoIP place on the network?
Voice is real-time data. The network can be subject to minimal delays and that can impact the quality of voice traffic. Voice needs an uninterrupted channel, and it has to be prioritized so calls are not interrupted. The network needs to be finely tuned, and carefully monitored and managed. It has to have enough bandwidth and quality of service needs to be implemented. A businesses need to be ready to upgrade its data network so that it can handle voice traffic.
You can't upgrade to a VoIP system without first doing a complete network evaluation. That is why companies often run into problems. They look at these systems and see that they are the same price as traditional systems. But they are not taking the time to understand the hidden costs. They need to ask themselves, 'Is the network ready? Is security in place?' That way, they will not have cost overruns. Too many companies think that all they need is bandwidth. But with voice, you need a virtual LAN, you need a pure switched environment, not a hub and switch. A lot of preparation is required for voice system and often at a high price. How does adding voice data change network security?
There are issues from the firewall through the network to the desktop. With VoIP, the phone becomes an intelligent end point. Now someone can access data network through the phone. Because of that, you need to secure the perimeter, internal desktop devices and soft switches. You need to authorize phone users and monitor the network. You need to do intrusion detection. And right now, data monitoring tools are not adequate for voice. What about other infrastructure details, such as cabling and power over Ethernet?
You need to have Cat 5 cable or higher to run voice. And IP phones need a source of power. So, businesses need to either install inline power or have an outlet at every desk. These are not huge expenses, but they can add up and companies should expect them.
Businesses need data people that understand the impact of voice on the network, and they have to have people that are trained with voice. The skill ownership is clearly in the data department. Training is important because people familiar with converged networks are in short supply. Some organizations start training long before deployment to get people up to speed. How important is training users?
If people do not know how to use the phone features, that is a problem. But one real plus is that the phones are very intuitive. Though it can take some training, in general the features are more accessible than on a standard phone. That is one of the benefits of IP telephony. How important is Session Initiation Protocol (SIP) as an emerging standard?
SIP is the foundation for all new applications, but it does have security vulnerabilities that one should be aware of. While it is the foundation for applications, it is still an emerging technology, and there are many proprietary features added to it.