Consider the figure below. Answer the following questions:

$1.$ Assuming FIFO service, indicate the time at which packets $2$ through $12$ each leave

the queue. For each packet, what is the delay between its arrival and the beginning

of the slot in which it is transmitted? What is the average of this delay over all $12$

packets?

$2.$ Now assume a priority service, and assume that odd$-$numbered packets are high priority,

and even$-$numbered packets are low priority. Indicate the time at which packets $2$

through $12$ each leave the queue. For each packet, what is the delay between its arrival

and the beginning of the slot in which it is transmitted? What is the average of this

delay over all $12$ packets?

$3.$ Now assume round robin service. Assume that packets $1,2,3,6,11,$ and $12$ are from

class $1,$ and packets $4,5,7,8,9,$ and $10$ are from class $2.$ Indicate the time at which

packets $2$ through $12$ each leave the queue. For each packet, what is the delay between

its arrival and its departure? What is the average delay over all $12$ packets?

$4.$ Now assume weighted fair queueing $($WFQ$)$ service. Assume that odd$-$ numbered

packets are from class $1,$ and even$-$numbered packets are from class $2.$ Class $1$ has

a WFQ weight of $2,$ while class $2$ has a WFQ weight of $1.$ Note that it may not be

possible to achieve an idealized WFQ schedule as described in the text, so indicate why

you have chosen the particular packet to go into service at each time slot. For each

$1$

packet what is the delay between its arrival and its departure? What is the average

delay over all $12$ packets?

$5.$ What do you notice about the average delay in all four cases $($FIFO$,$ RR$,$ priority, and

WFQ$)?$