  We consider a multihop wireless system. There are multiple source-destination
pairs. The data from a source may have to pass through multiple nodes. We
obtain a channel scheduling policy which can guarantee end-to-end mean delay
for the different traffic streams. We show the stability of the network for
this policy by convergence to a fluid limit. It is intractable to obtain the
stationary distribution of this network. Thus we also provide a diffusion
approximation for this scheme under heavy traffic. We show that the stationary
distribution of the scaled process of the network converges to that of the
Brownian limit. This theoretically justifies the performance of the system. We
provide simulations to verify our claims.
