Cross-layer congestion control mechanism for SCTP over EGPRS network

In this paper we propose a cross-layer algorithm between SCTP and RLC/MAC. Our approach proposes an analytical model of SCTP layer bandwidth variations according to EDGE link layer bandwidth changes. Tunable functions are proposed depending on the couple (MCS,BLER). This modeling is based on an effective cross-layer modeling, which adapts the congestion window size evolution to the radio transmission channel state. We introduce a congestion control mechanism modification consisting of restriction to the slow start phase. This cross-layer optimization allows congestion avoidance at transport layer caused by radio interface quality degradations. Our goal, in this study, is to provide a means that gives an optimal interaction model between transport layer (SCTP) and link layer (RLC/MAC EDGE), in order to improve network reliability.