Abstract: As fully adaptive routing algorithms make inefficient use of the buffer resources in routers,an improved virtual channel (VC) allocation scheme is proposed for wormhole switching Networks on Chip (NoCs). By comparing the credit counts of output VCs with the number of remaining flits of a packet,this scheme determines that a tail flit in a VC buffer will not be blocked at the current router.Hence,a released VC can be assigned to a pending packet before it is emptied,which improves the utilization of buffer resources.Simulation results in an 8×8 mesh network show that, compared with the conservative VC allocation scheme, this proposed scheme can increase the saturation injection rate of the network,or reduce the amount of buffer resources while maintaining an equivalent network performance.