real time

Posts Tagged ‘real time’

postheadericon Are You VoIP Ready?

If you are considering VoIP for your company – or more to the point, if YOU are responsible for the implementation of VoIP for your company – here are the basics you will need to understand.

Voice over IP performance is a function of:

a) Bandwidth

b) Latency

Both components have to be within a certain tolerance  in order to be usable and there are a multitude of factors that can adversely affect either. Many IT professionals who are first time VoIP-ers  often think that given enough bandwidth, you can do anything – including voice. This is only half true. A lack of bandwidth can cause latency, but an abundance of bandwidth is not a guarantee of a clear conversation. Of the two, latency is not only a show stopper, it is also the hardest one to find and correct because there are many causes that are often times not within your control. Figure 1 is a great example of a company with a bonded 6M T-1 connection with such erratic latency – and jitter  – that it is virtually unusable for

voice applications. In many cases like this, the most natural scapegoat is the carrier, however, in this case, hop 14 is the WAN side of the customer s router and hop 15 is a device behind it which implies a problem with the hardware. Here, the problem turned out to be one of the 4 T-1′s were in a permanent Admin Down  mode and needed to have the WIC replaced.

WARNING TO THOSE JUST GETTING INTO VoIP – Voice is real time  – using primarily UDP packets – and therefore much more affected by things like dropped packets, jitter and high latency than regular  data. If there are issues on your Internet connections with these items, you will probably not realize it unless you specifically – and continuously – test for it. Most carriers only guarantee bandwidth and NOT latency. Trust me, the CEO, CFO, Customer Service manager and Sales manager will get upset if the email server or Internet is a little slow, but they will absolutely FREAK if their phones don’t work.