Does your company have any remote employees? Do they use VoIP and are they experiencing choppy voice? You might find this post informative.

We have a few employees working remotely and of course we want them using our phone system however, dealing with call quality (aka QoS) can be a bit of a challenge. We have tried a couple of things.

First, we setup Vonage for the remote employee whereby, the employee uses the Vonage phone to speed dial the office for a dial tone and then dial the customer.

Second, we setup a VoIP phone that connected directly to the office whereby, no speed dial is necessary.

Which setup do you think saw better quality of service? I should also note that the employee has a Cisco Flexible NetFlow router capable of exporting Medianet statistics on the calls. In the screen capture below, you can see the two phones:

* VoIP to our office via the Internet
* VoIP to Vonage via the Internet

Notice above that suffers far worse quality of service. One call saw 23 lost packets and 7ms of Jitter. What is acceptable VoIP jitter? About 20-30ms according to some sources however, make sure you are looking at packet loss as well. More information on the Cisco Medianet metrics can be found by searching the web.

The Medianet Network Performance Monitoring information was indicative of what the remote employee was trying to tell us. VoIP quality stinks! There is much more VoIP Jitter and VoIP Packet Loss on the connection directly to our office. Ultimately, the Vonage call quality is better. Why?

Check out this trace route from his house to our office:

Check out this trace route from his house to Vonage:

Less hops to Vonage is probably a major factor in call quality. Be aware of the router hops when trouble shooting VoIP that leverages the Internet and make sure you take advantage of Medianet via Flexible NetFlow to report on call quality.


Thomas Pore is the Director of IT and Field Engineering at Plixer. He developed and leads, the Malware Incident Response and Advanced NetFlow Training programs which are being offered in cities across the USA. He is also an adjunct professor at the local community college and teaches ethical hacking. Thomas travels the globe meeting with customers and trying improve the Scrutinizer network incident response system. He helps clients optimize threat detection strategies and aids in the configuration of custom incident response solutions. He has a Bachelor of Science in Computer Science from Dickinson College.


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