Net2Plan

Example: Routing minimizing maximum link utilization, using flow-path formulation

fa_minimaxUtilization_xdp

This algorithm obtains the traffic routing that minimizes the maximum link utilization, using a linear flow-path formulation. For each demand, the set of admissible paths is given by the k loopless shortest paths between the demand end nodes. k > 0 is an input parameter to the problem.

The algorithm first computes the list of admissible paths (P_d, d in D). Then, solves the following formulation:

Decision variables:

  • lbrace x_{dp}, d in D, p  in P_d rbrace: Fraction in [0 , 1] of the traffic of demand d that traverses the admissible path p.

  • rho: Maximum utilization in the links

 min rho
 sum_{p in P_d} x_{dp} = 1 quad forall d in D
 sum_d sum_{p in P_{de}} h_d x_{dp} leq u_e rho quad forall e in E
 rho leq 1
 x_{dp} geq 0 quad forall d in D, p in P_d

In the previous formulation, the set P_{de} is composed of the paths p in P_d that traverse link e. The previous formulation is a linear program respect to the decision variables, and is solved using CVX. The algorithm requires CVX solver installed and running.

Download .m file: fa_minimaxUtilization_xdp.m