In order to guarantee quality of service (QoS) of different priority bursts and solve the problem of deflection control of deflection algorithm in OBS networks

a deflection routing algorithm based on priority and parameter-tunable in OBS networks is proposed.It intercalates the definition of a tunable-parameter (deflection probability) to control the deflection of contending bursts

and searches the optimum deflection path in terms of the burst loss probability and the deflection path length.When competition occurs

low priority bursts are segmented

and the segmentation part of bursts are deflected to free links.The algorithm selects many candidate routes which the tunable-burst loss probability of the first k priority burst and overall bursts in the deflection path is the least.At last

it chooses the shortest deflection path.Simulations show that the algorithm can reduce the burst loss probability of entire networks and protect the integrity of some high priority bursts.It also can efficiently reduce the delay

and reduce the offset time deficit on QoS guarantee.So the scheme can improve the performance of OBS networks.