Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17


flow deviation - principle

Posted on 1999-07-19
Medium Priority
Last Modified: 2012-05-04
solving questions regarding "optimized flow" using Flow Deviation algorithm is very hard.
Is there any principle (something with derivatives, the lecturer said) which helps solving such questions more easily?
Question by:eimoah
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
  • 2

Author Comment

ID: 1588992
Adjusted points to 60

Accepted Solution

shlomoy earned 240 total points
ID: 1588993
consider a "penalty function h(f)" where h(f) is the penalty (as a function of the flow f in an edge) of putting flow on an edge.

suppose yuou have a source S and a destination D and you have two paths p1 and p2 in which you can route flow from S to D.

derivating the funciton h(f) by f we get dh/df.
let's sign L by dh/fd.

Lets say that f(i) is the flow in edge i and that L(i) is the new metric for the edge i (with respect to the penalty function).

Say that source S has a total of Z units of flow to route towards D, and we decide to route X of that flow through p1 and the rest Z-X of the flow via p2.

if you're asked what is the optimized routing of the flow such that the penalty is reduced to it's minimum then you'd have to solve the following equation:

sum all L(i)'s (where i represents every edge in path in path p1) and equate it with the sum of all L(j) (where j represents every edge in path in path p2).

solving that equation for X you find the optimized routing for our case.

Sorry for the complex explenation, but since I can't use math-notations with these fonts, it's hard to give you verbaly a general explenation.

you can email me at for more information.


Author Comment

ID: 1588994
I think I've got it.
I hope you didn't mind gettinbg my emails.


Featured Post

Plesk WordPress Toolkit

Plesk's WordPress Toolkit allows server administrators, resellers and customers to manage their WordPress instances, enabling a variety of development workflows for WordPress admins of all skill levels, from beginners to pros.

See why 2/3 of Plesk servers use it.

Question has a verified solution.

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

This article explains the fundamentals of industrial networking which ultimately is the backbone network which is providing communications for process devices like robots and other not so interesting stuff.
This article will show how Aten was able to supply easy management and control for Artear's video walls and wide range display configurations of their newsroom.
In this tutorial you'll learn about bandwidth monitoring with flows and packet sniffing with our network monitoring solution PRTG Network Monitor ( If you're interested in additional methods for monitoring bandwidt…
If you're a developer or IT admin, you’re probably tasked with managing multiple websites, servers, applications, and levels of security on a daily basis. While this can be extremely time consuming, it can also be frustrating when systems aren't wor…

670 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