TY - JOUR

T1 - Optimal Representations of a Traffic Distribution in Switch Memories

AU - Sadeh, Yaniv

AU - Rottenstreich, Ori

AU - Barkan, Arye

AU - Kanizo, Yossi

AU - Kaplan, Haim

N1 - Publisher Copyright:
© 1993-2012 IEEE.

PY - 2020/4

Y1 - 2020/4

N2 - Traffic splitting is a required functionality in networks, for example for load balancing over multiple paths or among different servers. The capacity of each server or path implies the distribution by which traffic should be split. A recent approach implements traffic splitting within the ternary content addressable memory (TCAM), which is often available in switches. It is important to reduce the amount of memory allocated for this task since TCAMs are power hungry and are often also required for other tasks such as classification and routing. For splitting a universe of ^{W}$ addresses into $k$ pieces of particular sizes, we give a simple algorithm that computes an optimal representation in $O(Wk)$ time. Furthermore, we prove that a recently published load balancer, called Niagara, which runs in $O(Wk\log k)$ time is in fact optimal. That is, both our algorithm and Niagara produce the smallest possible TCAM that splits the traffic exactly to the required pieces, where the only previously known algorithm for computing optimal exact representation has running time exponential in $k$. Finally, we use these optimal algorithms to experimentally study the number of TCAM rules required to split traffic in typical scenarios.

AB - Traffic splitting is a required functionality in networks, for example for load balancing over multiple paths or among different servers. The capacity of each server or path implies the distribution by which traffic should be split. A recent approach implements traffic splitting within the ternary content addressable memory (TCAM), which is often available in switches. It is important to reduce the amount of memory allocated for this task since TCAMs are power hungry and are often also required for other tasks such as classification and routing. For splitting a universe of ^{W}$ addresses into $k$ pieces of particular sizes, we give a simple algorithm that computes an optimal representation in $O(Wk)$ time. Furthermore, we prove that a recently published load balancer, called Niagara, which runs in $O(Wk\log k)$ time is in fact optimal. That is, both our algorithm and Niagara produce the smallest possible TCAM that splits the traffic exactly to the required pieces, where the only previously known algorithm for computing optimal exact representation has running time exponential in $k$. Finally, we use these optimal algorithms to experimentally study the number of TCAM rules required to split traffic in typical scenarios.

KW - Computer network management

KW - algorithms

KW - data structures

KW - packet switching

UR - http://www.scopus.com/inward/record.url?scp=85083716607&partnerID=8YFLogxK

U2 - 10.1109/TNET.2020.2977477

DO - 10.1109/TNET.2020.2977477

M3 - מאמר

AN - SCOPUS:85083716607

VL - 28

SP - 930

EP - 943

JO - IEEE/ACM Transactions on Networking

JF - IEEE/ACM Transactions on Networking

SN - 1063-6692

IS - 2

M1 - 9032315

ER -