Medianet Reference Guide - Cisco

Cisco Network Analysis Module
Chapter 6
Medianet Management and Visibility Design Considerations
Figure 6-19
Detailed Graph of Multiple UDP Jitter IPSLA Operations Simulating a Cisco
TelePresence CTS-1000
From Figure 6-19, it appears that UDP jitter IPSLA operations #1 and #2 space their packets each
1 millisecond apart. However, this is just because of the graphing of the data points. The actual data trace
reveals that the Cisco Catalyst 6500 switch sends packets from both UDP jitter IPSLA operations
roughly back-to-back every four milliseconds. Therefore, the IPSLA-simulated video packets are
slightly more clumped together than actual TelePresence video packets, but still considered acceptable
from a pre-assessment perspective. The third UDP jitter IPSLA operation generates a simulated audio
stream of packets every 20 milliseconds. Note that a CTS-1000 can receive up to three audio streams and
an additional auxiliary video stream for presentations. Simulation of these streams are not shown in this
example for simplicity. However, the method discussed above can be extended to include those streams
as well if needed. Likewise, the method may be used to simulate other video flows simply by capturing
a data trace, analyzing the flow, and setting up the appropriate IPSLA operations.
The configuration snippet on Example 6-3 shows the configuration of the UDP jitter IPSLA operations
on the Cisco Catalyst 6500 switch that were used to create the simulation from which the data in
Figure 6-19 was captured.
Example 6-3
IPSLA Sender Configuration on a Cisco Catalyst 6500 Series Switch
ip sla monitor 24
type jitter dest-ipaddr 10.24.1.11 dest-port 32800 source-ipaddr 10.16.1.1 source-port
32800 num-packets 16500 interval 2
request-data-size 1018
tos 128
ip sla monitor 25
type jitter dest-ipaddr 10.24.1.11 dest-port 32802 source-ipaddr 10.16.1.1 source-port
32802 num-packets 16500 interval 2
request-data-size 1018
tos 128
ip sla monitor 26
type jitter dest-ipaddr 10.24.1.11 dest-port 32804 source-ipaddr 10.16.1.1 source-port
32804 num-packets 3300 interval 20
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Medianet Reference Guide
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