Scheduling Time-Sensitive IP Traffic

Pedro Sousa, Paulo Carvalho and Vasco Freitas

Universidade do Minho
Departamento de Informática
P-4710-057 Braga, Portugal

Tel.: +351 253 604430
Fax.: +351 253 604471
E-mail: {pns,pmc,vf} (at)


This article presents an hybrid priority queuing model based scheduler for real-time traffic differentiation. The proposed scheduler is designed as a mechanism to provide queuing delay differentiation among real-time traffic classes. The novel characteristic of the presented scheduler is the capability to simultaneously try to achieve an upper time limit for queuing delays and, under heavy load conditions, deny class starvation by providing an expectable differentiation schema for excess queuing delays. The attractiveness of the proposed scheduler is its hybrid differentiation capabilities based on a simple queue selection procedure. Additionally, the enhanced differentiation behavior of the scheduler is also highlighted as three distinct configuration modes are possible.

6th IFIP/IEEE International Conf on Management of Multimedia Networks and Services (MMNS 2003), Queen's University Belfast, N Ireland, Sep 7-10, 2003       LNCS, vol 2839, pp. 368-380, Springer-Verlag, 2003