Today I’ll cover the importance of VoIP DSCP prioritization when NetFlow reporting.  We have 3 employees that work remotely in Central Maine, Pennsylvania, and Florida.  They all have Cisco routers and are exporting VoIP data to our NetFlow Analyzer server.  Read the Cisco Medianet Deployment Guide to learn more about setting this up.

Jim works in Florida, which is 13 hops from our PBX here in Southern Maine.

VoIP router hops

He has a business class internet account and, because of this, we believe they prioritize his VoIP traffic.  The quality of his calls is very good, ~7ms of jitter.

VoIP Jitter monitoring

You want to make sure you prioritize the traffic coming from your desk phone, or configure your soft phone to send prioritized traffic.

VoIP DSCP settings

We use Cisco performance reporting for Medianet’s functionality to verify QoS as well as traffic volumes caused by the G.729 vs. G.711u codecs.  My point here is that these new exports are very helpful and I’m sure you’ll appreciate them.  BTW: We are running IOS v15.2(2)T and the above required Flexible NetFlow Configuration to get the additional fields exported.

On that note, with NetFlow v9 and Flexible NetFlow so prevalent now, how often is ip route-cache flow used?

Joanne Ghidoni author pic

Joanne Ghidoni

Joanne is a Software Quality Assurance Engineer at Plixer. She has also held positions as Technical Support Engineer and Sales Engineer since joining Plixer in 2005. Prior to joining Plixer, Joanne has had numerous positions in the IT field, including data entry, computer operator, PC coordinator and support, mainframe programmer, and also Technical Support and web programmer at Cabletron Systems. In her spare time, Joanne enjoys traveling, always seeking out new and interesting places to visit.


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