The Net-tools package contains the arp, hostname, ifconfig, netstat, plipconfig, rarp, route, and slattach programs.
arp is used to manipulate the kernel's ARP cache, usually to add or delete an entry, or to dump the ARP cache.
hostname, with its symlinks domainname, dnsdomainname, nisdomainname, ypdomainname, and nodename, is used to set or show the system's hostname (or other, depending on the symlink used).
The ifconfig command is the general command used to configure network interfaces.
netstat is a multi-purpose tool used to print the network connections, routing tables, interface statistics, masquerade connections, and multicast memberships.
plipconfig is used to fine-tune the PLIP device parameters, hopefully making it faster.
Akin to the arp program, the rarp program manipulates the system's RARP table.
route is the general utility which is used to manipulate the IP routing table.
slattach attaches a network interface to a serial line, i.e.. puts a normal terminal line into one of several "network" modes.