Admission Control of VL in AFDX Under HRT Constraints

Avionics full duplex switched ethernet (AFDX) is a switched interconnection technology developed to provide reliable data exchange with strong data transmission time guarantees in internal communication of the spacecraft or aircraft. Virtual link (VL) is an important concept of AFDX to meet quality of service (QoS) requirements in terms of end-to-end message deadlines. A VL admission control algorithm in AFDX network under hard real-time (HRT) constraints is studied. Based on the scheduling principle of AFDX protocol, a packet scheduling scheme under HRT constraints is proposed, and after that an efficient VL admission control algorithm is presented. Analytical proof that the algorithm can effectively determine whether VL should be admitted is given. Finally simulative examples are presented to promote the conclusion.