$($a$)$ Two $(2)$ of the three $(3)$ types of services provided to the Network Layer by the Data Link Layer are "Unacknowledged connectionless service" and "Acknowledged connectionless service".

$($i$)$ Briefly explain the difference between Unacknowledged connectionless service and Acknowledged connectionless service.

$(3$ marks$)$

$($ii$)$ Describe how error control is performed for each service.

$(3$ marks$)$

$($iii$)$ Provide an example of appropriate use of each type.

$(3$ marks$)$

$($b$)$ Draw an Internet Control Message Protocol $($ICMP$)$ message format and indicate the bytes size of the header.

$(6$ marks$)$

$($c$)$ Briefly explain what is meant by broadcasting and multicasting.

$(2$ marks$)$