VoIP Deployment

You've got enough going on with the network without consolidating data and voice onto a single link but the old phone system dialed its last number and has moved on to the CAT3 valley in the sky.  Your company is deploying a new Voice Over IP system pronto, and you're responsible for ensuring 100% quality 100% of the time.  What do you do?

Planning and Gathering Network Baseline Data

It doesn't matter if you have one week or one year to plan, take as much time as possible to plan for the new phone system.  Calls across the LAN (local area network) are probably not a big concern for regular office environments as far as bandwidth is concerned, but you will want to make sure your network can support the additional load.  Gigabit ethernet with power over ethernet (POE) support are common features on most enterprise class switches and will make this process a lot easier for your LAN.  But what about your Wide Area Network (WAN)?  You'll need to understand how many simultaneous calls your company will need to support and make sure the necessary bandwidth is there to support it.  NetCore On Demand easily lets you report on link utilization and lets you group traffic into buckets based on business priority so you can easily see how much bandwidth is avaialble during peak business hours, and how much you can recover by controlling recreational and non business app usage.  In short, you'll want to ensure that your business critical applications will still perform even during periods of maximum call volume.  During your VoIP capacity planning process you should consider the following:

• Your local area network (LAN) and/or wide area network (WAN)
• Existing data traffic on the network
• The voice codecs your VoIP solution will use
• Connectivity to the Public Switched Telephone Network (PSTN)
• Your network's hardware infrastructure
• VoIP and network redundancy

Performing VoIP baselines

Now that you have a general idea of how much VoIP traffic to expect you can begin to test how the new traffic will impact the network.

NetCore On Demand will provide detailed information on how much bandwidth you're using and help identify potential problems.  You can then use simple VoIP simulators to accurately replicate different types of voice traffic across the network and watch for errors or congestion.  They can monitor for VoIP problems such as jitter and delay. Jitter is the measurement of transit delay in voice packets and can be caused by many reasons. The end result is lower quality communications. You can select different VoIP codecs and simulate different call loads during real-time tests. Different codecs, such as G.711 and G.729, provide different sampling rates that affect packet size.

Selecting a lower quality codec can dramatically affect the bandwidth usage on network links. During your test you should also test compression, which can increase available network resources and allow for more simultaneous phone calls.

Routing the Calls

Now you'll want to determine if each remote location with have local PSTN connectivity or if you're going to route all calls to a central location.  If you have a single, central PSTN all phone calls would pass across the WAN to the central site where they would proceed out the associated PSTN gateway.  Centralizing PSTN connectivity can simplify voice planning and the resulting hardware consolidation can decrease costs and maintenance.  This deployment will also increase the number of calls across the WAN which will increase network traffic and create a dependancy on a functioning WAN to make any phone calls.

Plan for Troubleshooting

Your users will have long standing expectations as to how a phone should perform.  Expect the unexpected and understand that end users will be quick to complain about call performance and relability.  Make sure you have the tools in place to properly monitor and troubleshoot VoIP performance.  It's inevitable that there will be issues so having the tools to understand the problem and prevent it from happening in the future should be your number one goal.  NetCore On Demand can provide you with detailed VoIP performance reports and can integrate with many different network monitoring tools to centralize VoIP metrics such as latency, jitter, delay, r-value and MOSS scores.  NetCore On Demand's real time reporting interface lets you quickly troubleshoot and identify VoIP issues, determine the root cause, and the assist in the implementation of policies to ensure the issue doesn't happen again.  Few VoIP deployments go perfectly, but with NetCore you'll be prepared to make sure yours does.