Network Security $[8$ Points$]$ Dynamic Host Configuration Protocol $($DHCP$)$ is used by a laptop during WiFi access to obtain the IP address of the Gateway $($every packet from a machine destined for the Internet goes through the Gateway$)$ and the IP address of the DNS server $($DNS server is used to resolve names to IP addresses$).($a$)[2$ Points$]$ Why is DHCP subject to security attacks? $($b$)[6$ Points$]$ What kinds of attack can happen?