Sample midterm questions for CS 4633. Spring 2005
- (5 points) In this question, you are asked to draw an event-graph for the router system shown in the below figure.
H
The above router receives mix of high priority and low priority packets. After receiving the packets, the router places them into the appropriate queues. The transmitter first sends all the packets from the high priority queue. When the high priority queue is empty, the transmitter sends the packets from the low priority queue without preemption.
Capacity of each queue is 100 packets.
Inter-arrival time tA between all types of packets has an exponential distribution with mean 0.9ms.
On average, P% of the incoming packets has high priority, while the others have low priority.
Service time tS has exponential distribution with mean 0.8ms for all types of packets.
We are interested in measuring what portion of the high priority and low priority packets is lost under different values of P (e.g., P=10, 20, 30).