Voice Probes Inquiry???

Charlie Mayes · ‎09-10-2009

Hello All,

I once read something about a Cisco router or Gateway being able to send out probes to simulate voice traffic over the WAN. Then once you recieve the signals back you can analyze them to determine how those packets were treated. What was that called again and how do I go about enabling it on both routers?

virverma · ‎09-15-2009

There are good tools available which can simulate voice traffic,

check in link,

http://www.cisco.com/web/about/ciscoitatwork/network_systems/network_data_monitoring_and_reporting_web.html

but if you want to see real time network output where QOS has been applied,

check the show commands in,

http://www.cisco.com/en/US/tech/tk652/tk698/technologies_configuration_example09186a0080094af9.shtml#topic14

Nicholas Matthews · ‎09-15-2009

The feature is called IP SLA.

Here is some example configuration /show commands:

Sending side:

ip sla monitor 3

type jitter dest-ipaddr 172.16.1.2 dest-port 16384 codec g711ulaw codec-numpackets 30

tos 184

frequency 10

ip sla monitor schedule 3 start-time now

ip sla monitor 4

type jitter dest-ipaddr 172.16.35.5 dest-port 16386 codec g711ulaw codec-numpackets 20

tos 184

frequency 5

ip sla monitor schedule 4 start-time now

Receiving side:

ip sla monitor responder

R3#sh ip sla moni stat

Round trip time (RTT) Index 3

Latest RTT: 54 ms

Latest operation start time: 00:11:46.823 UTC Tue Jan 1 2008

Latest operation return code: OK

RTT Values

Number Of RTT: 13

RTT Min/Avg/Max: 108/124/153 ms

Latency one-way time milliseconds

Number of one-way Samples: 0

Source to Destination one way Min/Avg/Max: 0/0/0 ms

Destination to Source one way Min/Avg/Max: 0/0/0 ms

Jitter time milliseconds

Number of Jitter Samples: 7

Source to Destination Jitter Min/Avg/Max: 5/6/7 ms

Destination to Source Jitter Min/Avg/Max: 1/1/1 ms

Packet Loss Values

Loss Source to Destination: 17 Loss Destination to Source: 0

Out Of Sequence: 0 Tail Drop: 0 Packet Late Arrival: 0

Voice Score Values

Calculated Planning Impairment Factor (ICPIF): 25

Mean Opinion Score (MOS): 3.50

Number of successes: 20

Number of failures: 0

Operation time to live: 3393 sec

Round trip time (RTT) Index 4

Latest RTT: 2 ms

Latest operation start time: 00:12:01.167 UTC Tue Jan 1 2008

Latest operation return code: OK

RTT Values

Number Of RTT: 20

RTT Min/Avg/Max: 2/2/2 ms

Latency one-way time milliseconds

Number of one-way Samples: 0

Source to Destination one way Min/Avg/Max: 0/0/0 ms

Destination to Source one way Min/Avg/Max: 0/0/0 ms

Jitter time milliseconds

Number of Jitter Samples: 19

Source to Destination Jitter Min/Avg/Max: 0/0/0 ms

Destination to Source Jitter Min/Avg/Max: 0/0/0 ms

Packet Loss Values

Loss Source to Destination: 0 Loss Destination to Source: 0

Out Of Sequence: 0 Tail Drop: 0 Packet Late Arrival: 0

Voice Score Values

Calculated Planning Impairment Factor (ICPIF): 1

Mean Opinion Score (MOS): 4.34

Number of successes: 6

Number of failures: 0

Operation time to live: 3570 sec

Hope this helps.

-nick