Patent ID: 6657987
Filing Date: 2003-12-02
Classification: H04L

Abstract:
A method of scheduling of connections with quality of service (QoS) constraints in a polling based media access control (MAC) scheduling methodology for Master-driven Time Division Duplex (TDD) systems comprising the steps of:a) calculating a polling interval, Ts, according to Ts=ks&it;Lsmax&af;(1rs-1R),where rs is a token rate, R is a service rate, ks is a number of packets served in each session s, and Lsmax is a maximum packet length for session s; b) calculating a deadline as deadline(i)=current time+Ti; c) finding a queue with the earliest deadline; d) serving the queue with up to ks packets, a number of packets served being ksi, where i is the ith visit to the session s; e) if ksi equals ks and the number of packets, Ni, left in the queue is greater than zero, then setting deadline(s) equal to the current time plus a polling interval calculated as Tsi=max&af;((Ts+Nsi&it;LsmaxR),Ts-Bs),where Bs is a bucket size for the session s; f) if ksi is less than ks, then setting deadline(s) equal to the current time plus a polling interval calculated as Tsi=min&af;((Ts+(ks-ksi)&it;LsmaxR),Ts+Bs);g) if ksi equals ks and the number of packets, Ni, left in the queue is zero, then setting deadline(s) equal to the current time plus a polling interval calculated as in step a); h) if a new connection has arrived, repeat beginning at step a); i) else go back to step c).