$[$ Select $]["$ACK$","$ad hoc mode", "ARP", "authenticity", "authoritative DNS server", "autonomous system", "availability", $"$BGP$",$ "botnet", $"$BSS$",$ "CIDR", "confidentiality", "DDoS attack", $"$DHCP$",$ "end system", "FIN", "ICMP", "infrastructure mode", "integrity", "netmask", "non$-$repudiation", "persistent cookie", "propagation delay", "protocol", "queuing delay", "root DNS server", "router", $"$RST$",$ "session cookie", "SSID", $"$SYN$","$TLD DNS server", "transmission delay", "type A resource record", "type CNAME resource record", "type MX resource record", "type NS resource record", "virus", "worm", "zero$-$day attack", "zombie"$]-$ any user computing device connected to the network, also called a host