?
Solved

how to calculate delay jitter given delay.

Posted on 2007-04-10
1
Medium Priority
?
3,928 Views
Last Modified: 2008-01-09
Hi experts,

I understand that delay jitter is the variation of delay in network packet measurement.
So given delay, how do I calculate delay jitter?
If delay jitter is the variance, can I use the usual statistic variance formula var(X)=E(X^2)-E(x)^2?
If my delay is given in millisecond, what is the unit of delay jitter?
0
Comment
Question by:help-me
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
1 Comment
 
LVL 3

Accepted Solution

by:
jimmyd072298 earned 150 total points
ID: 18994624
Not really the actual function is a simple example of a class of estimators called "recursive prediction error" or "stochastic gradient algorithms".  .Think about as a recursive running average.  To calculate you have to remember that nothing is known about absolute transit times, the differences in packet transit times are independent of absolute clock values. If packets i and j are time stamped with timestamps Si and Sj when they are sent and are received at times Ri and Rj, respectively, then Dij = (Rj-Sj) - (Ri-Si) = (Rj-Ri)-(Sj-Si) is the difference in transit times in time stamp units. Knowing that then jitter is a smoothed function of |Di-1,i|:Ji = Ji-1 + ( |Di-1,i| - Ji-1 )/16 = 15/16 * Ji-1 + 1/16 * |Di-1,i|
Thus, jitter is a sort of running average of all |Di-1,i| from the beginning of the measurement up to the current packet. Recent packets have a larger weight than older packets. The jitter curve needs about 100 packets to stabilize.
0

Featured Post

On Demand Webinar - Networking for the Cloud Era

This webinar discusses:
-Common barriers companies experience when moving to the cloud
-How SD-WAN changes the way we look at networks
-Best practices customers should employ moving forward with cloud migration
-What happens behind the scenes of SteelConnect’s one-click button

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

ADCs have gained traction within the last decade, largely due to increased demand for legacy load balancing appliances to handle more advanced application delivery requirements and improve application performance.
This month, Experts Exchange’s free Course of the Month is focused on CompTIA IT Fundamentals.
This video gives you a great overview about bandwidth monitoring with SNMP and WMI with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're looking for how to monitor bandwidth using netflow or packet s…
Monitoring a network: why having a policy is the best policy? Michael Kulchisky, MCSE, MCSA, MCP, VTSP, VSP, CCSP outlines the enormous benefits of having a policy-based approach when monitoring medium and large networks. Software utilized in this v…

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question