-ml n: The upper limit of the lost packets number during multi-cast process. If the lost packets number is larger than n, the multi-cast will continue the second loop. After the second loop, the multi-cast process will end whether the lost packets number is larger than n or not. -sl n: The upper limit of the lost packets number to be resend by TCP mode. If the lost packets number is larger than n, XImage will give up resending them and then return fail.