Bandwidth constrained routing problem in multi-hop wireless networks

Abstract

The Bandwidth-Constrained Routing Problem (BCRP) asks for a route that has sufficient bandwidth for data transmission. When BCRP is defined for wired networks, it can be solved in polynomial time. On the other hand, when it is defined for multi-hop wireless networks, it is NP-complete if the underlying MAC protocol is TDMA-based or CDMA-over-TDMA-based. In this paper, we show that BCRP is still NP-complete, even if CSMA-based or contention-based CDMA MAC protocols are used. Besides, we show that BCRP is polynomial-time solvable if the underlying MAC protocol adopts CDMA channel model and FIFO scheduling policy. In multi-hop wireless networks, no MAC protocol was designed before which would lead to a polynomial-time solution to BCRP. The results of this paper suggest a design principle for MAC protocols that can support QoS routing well.