SAA (rtr) Jitter, delay how to read the statistics?

sophiaconseil · ‎08-05-2011

Hi eveybody,

I've set QoS throughout the whole network, and I have set SAA to test if everything works the way I want. I've typed the command

sh rtr collection-statistics but then I don't understand what's being displayed. There's not much information on cisco's website except some defenition of the terms which don't help me much and I'm wondering how I'm supposed to measure de jitter between my router A and B.

If someone could tell me how to read it simply, I just want the delay from source to destination and the vice-versa.

If someone knows some other way to measure those values, well I'll try it.

Thank you in advance.

CR_1#sh rtr collection-statistics

Entry number: 1

Start Time Index: .12:34:06.404 CEST Fri Aug 5 2011

Number of successful operations: 60

Number of operations over threshold: 0

Number of failed operations due to a Disconnect: 0

Number of failed operations due to a Timeout: 0

Number of failed operations due to a Busy: 0

Number of failed operations due to a No Connection: 0

Number of failed operations due to an Internal Error: 0

Number of failed operations due to a Sequence Error: 0

Number of failed operations due to a Verify Error: 0

Voice Scores:

MinOfICPIF: 0 MaxOfICPIF: 0 MinOfMOS: 0 MaxOfMOS: 0

RTT Values:

NumOfRTT: 59219 RTTAvg: 41 RTTMin: 29 RTTMax: 325

RTTSum: 2436709 RTTSum2: 105338059

Packet Loss Values:

PacketLossSD: 19 PacketLossDS: 229

PacketOutOfSequence: 0 PacketMIA: 533 PacketLateArrival: 0

InternalError: 0 Busies: 0

Jitter Values:

MinOfPositivesSD: 1 MaxOfPositivesSD: 124

NumOfPositivesSD: 20331 SumOfPositivesSD: 109748 Sum2PositivesSD: 890214

MinOfNegativesSD: 1 MaxOfNegativesSD: 28

NumOfNegativesSD: 33377 SumOfNegativesSD: 109967 Sum2NegativesSD: 536367

MinOfPositivesDS: 1 MaxOfPositivesDS: 60

NumOfPositivesDS: 16551 SumOfPositivesDS: 41946 Sum2PositivesDS: 254888

MinOfNegativesDS: 1 MaxOfNegativesDS: 36

NumOfNegativesDS: 18658 SumOfNegativesDS: 41557 Sum2NegativesDS: 206045

Interarrival jitterout: 0 Interarrival jitterin: 0

One Way Values:

NumOfOW: 133

OWMinSD: 121 OWMaxSD: 132 OWSumSD: 16777 OWSum2SD: 2117655

OWMinDS: 1 OWMaxDS: 201 OWSumDS: 4959 OWSum2DS: 389027

Start Time Index: .13:34:06.401 CEST Fri Aug 5 2011

Number of successful operations: 22

Number of operations over threshold: 0

Number of failed operations due to a Disconnect: 0

Number of failed operations due to a Timeout: 0

Number of failed operations due to a Busy: 0

Number of failed operations due to a No Connection: 0

Number of failed operations due to an Internal Error: 0

Number of failed operations due to a Sequence Error: 0

Number of failed operations due to a Verify Error: 0

Voice Scores:

MinOfICPIF: 0 MaxOfICPIF: 0 MinOfMOS: 0 MaxOfMOS: 0

RTT Values:

NumOfRTT: 21685 RTTAvg: 40 RTTMin: 29 RTTMax: 165

RTTSum: 876298 RTTSum2: 36001570

Packet Loss Values:

PacketLossSD: 16 PacketLossDS: 116

PacketOutOfSequence: 0 PacketMIA: 183 PacketLateArrival: 0

InternalError: 0 Busies: 0

Jitter Values:

MinOfPositivesSD: 1 MaxOfPositivesSD: 129

NumOfPositivesSD: 7347 SumOfPositivesSD: 38547 Sum2PositivesSD: 298911

MinOfNegativesSD: 1 MaxOfNegativesSD: 27

NumOfNegativesSD: 12315 SumOfNegativesSD: 38583 Sum2NegativesSD: 177697

MinOfPositivesDS: 1 MaxOfPositivesDS: 15

NumOfPositivesDS: 5962 SumOfPositivesDS: 15738 Sum2PositivesDS: 88530

MinOfNegativesDS: 1 MaxOfNegativesDS: 16

NumOfNegativesDS: 7626 SumOfNegativesDS: 15696 Sum2NegativesDS: 65900

Interarrival jitterout: 0 Interarrival jitterin: 0

One Way Values:

NumOfOW: 0

OWMinSD: 0 OWMaxSD: 0 OWSumSD: 0 OWSum2SD: 0

OWMinDS: 0 OWMaxDS: 0 OWSumDS: 0 OWSum2DS: 0

Richard Michael · ‎08-05-2011

Hello Vincent,

Please see the link below in order to have a detailed understanding on the

sh rtr collection-statistics

http://www.cisco.com/en/US/docs/ios/12_3/configfun/command/reference/cfr_1g09.html#wp1080239

Please note : Effective with Cisco IOS Release 12.3(14)T, the show rtr collection-statistics command is replaced by the show ip sla monitor collection-statistics command.

Thanks,

Ricky Micky

Rate this answer if it is helpful to you

sophiaconseil · ‎08-08-2011

Well thank you for your reply, unfortunately it didn't really answer my question, the page you refered me to doesn't give much information on how to deduce the jitter in ms from source to destination and vice versa. The définition of the different values give me much help on how to put them together in order to find the information I'm looking for.

If you know a way of doing it, please let me know and show me an example with the statistic I posted the last time.

Thank you.

Richard Michael · ‎08-08-2011

Hello Vincent,

You can refer the tabulation 101 in the above link to get the definition of the different values,

Jitter Values:

Indicates that Jitter statistics appear on the following lines.

Jitter is inter-packet delay variance.

NumOfJitterSamples:

The number of jitter samples collected. This is the number of samples that are used to calculate the following jitter statitstics.

MinOfPositivesSD

MaxOfPositivesSD

The minimum and maximum positive jitter values from source to destination, in milliseconds.

NumOfPositivesSD

The number of jitter values from source to destination that are positive (i.e., network latency increases for two consecutive test packets).

SumOfPositivesSD

The sum of those positive values (in milliseconds).

Sum2PositivesSD

The sum of squares of those positive values.

MinOfNegativesSD

MaxOfNegativesSD

The minimum and maximum negative jitter values from source to destination. The absolute value is given.

NumOfNegativesSD

The number of jitter values from source to destination that are negative (i.e., network latency decreases for two consecutive test packets).

SumOfNegativesSD

The sum of those values.

Sum2NegativesSD

The sum of the squares of those values.

Interarrival jitterout:

The source to destination(SD) jitter value calculation, as defined in RFC 1889.

Interarrival jitterin:

The destination to souce (DS) jitter value calculation, as defined in RFC 1889.

One Way Values

Indicates that one way measurement statistics appear on the following lines.

One Way (OW) Values are the amount of time it took the packet to travel from the source router to the target router (SD) or from the target router to the source router (DS).

NumOfOW

Number of successful one way time measurements.

OWMinSD

Minimum time from the source to the destination.

OWMaxSD

Maximum time from the source to the destination.

OWSumSD

Sum of the OWMinSD and OWMaxSD values.

OWSum2SD

Sum of the squares of the OWMinSD and OWMaxSD values.

Coming to the Jitter calculation, I have taken the values from the output that you have posted initially,

Formula :

rttMonLatestJitterOperAvgJitter = (jitterSum / jitterNum)

Where:

jitterSum = sumOfPositiveDS + sumOfNegativeDS + sumOfPositiveSD + sumOfNegativeSD

jitterNum = "Number of DS jitter samples" + "Number of SD jitter samples"

SumOfPositivesDS: 41946 ;

SumOfNegativesDS: 41557

SumOfPositivesSD: 109748

SumOfNegativesSD: 109967

NumOfPositivesDS: 16551

NumOfNegativesDS: 18658

NumOfNegativesSD: 33377

NumOfPositivesSD: 20331

Avg Jitter = 303218/88917 = 3ms

Hope this helps.

Thanks,

Ricky Micky

Pls Rate if this is useful

sophiaconseil · ‎08-08-2011

Well thank you very much, it really helps me, so I guess the jitter in my network is not too bad. Thank you again.

carl_rieger · ‎06-27-2012

I am just delving into the use of rtr, and I am having a problem of obtaining the One Way Values.

I have synchronized my clocks, and I obtain One Way Values after I have reloaded both routers and have started the rtr. However, after a period of time, these revert to 0. Even after I reset the rtr and configure a new rtr, these remain at 0.

Any insight would be appreciated.