[ns] Date: Mon, 24 Dec 2001 21:40:59 +0800

["Jie Chen" <kou0083@sina.com.cn>]

I'm trying to implement SCED in ns, but I got some problems.
1. What triggers a packet to be enqueued or dequeued in ns?
You can write a class to have enqueue() and dequeue() as its methods, but
when will they be called? Since the several queues that actually contain the
packets are maintained by the user, how can ns know that there are
backlogged packets? and then if the algorithm is work-conserving, how can ns
guarantee that?
2. The SCED algorithm requires that you have to know the time of the
network. Upon receiving a packet, you have to use that value to calculate
the time stamp, but how can you to get the time from ns? This is not the
packet arrival time.

Are there any ns implementations of SCED on the Internet? or are there any
people who have done similar work before can help me to finish the job?
Thanks in advance.