What are the functions of the following tcpip utilities nslookup winipcfg and microsoft snmp agent?

Nslookup: displays information about domain names and their ip addresses

Winipcfg: A win9x/me utility to display ip address and other configuration in a user friendly window.

Ipconfig: Displays the ip address of the host and other connection information

Microsoft snmp agent: provides system management tools for networks