We studied queueing delay, the graph in the slide shows that as traffic intensity approaches 1, the average queueing delay increases significantly. In other words, if the arrival rate is close to the service rate, which is the rate at which packets are transmitted on to the link, queueing delay will build up (think of standing in line at Starbucks during busy hours). Under certain assumptions, average queueing delay (or expected value of waiting time) is given by E[W] = (La/R) (2) - where a is the arrival rate, L is the average packet length, and R is the transmission rate. The ratio R/L is the departure rate. This equation assumes that departure rate is more than arrival rate because otherwise the length of the queue will increase indefinitely.

  

Q5. On chapter 1, we studied queueing delay, the graph in the slide shows that as traffic intensity approaches 1, the average queueing delay increases significantly. In other words, if the arrival rate is close to the service rate, which is the rate at which packets are transmitted on to the link. queueing delay will build up (think of standing in line at Starbucks during busy hours). Under certain assumptions, average queueing delay (or expected value of waiting time) is given by E[W] = = (La/R) (+)- - a where a is the arrival rate, L is the average packet length, and R is the transmission rate. The ratio R/L is the departure rate. This equation assumes that departure rate is more than arrival rate because otherwise the length of the queue will increase indefinitely.