Quick Setup Guide

Configuring and Troubleshooting VoIP Monitoring
12 November 2013
The RTP packets are encapsulated in UDP, IP, and Ethernet envelopes as shown in
Figure 3.
Audio data is also encoded using different formatting protocols. The audio format
used has nothing to do with transport over a network, so it is not shown as an
encapsulation in Figure 2.
Cisco monitoring and recording software and hardware supports several audio data
formats, including G.711 (mulaw and alaw), G.729, and G.722. These formatting
protocols are used to encode the audio data for transport over the network. Some
formats, like G.729, greatly compress the data so it can be transported over a network
faster.
Figure 3. Audio data encapsulation