ping companyweb ; test packets to and from a host, host IP is determined by DNS and shown tracert http://www.google.com ; trace route follows packets from inception to destination through local and wide networks arp -a ; Address Resolution Protocol links IP to physical address (MAC), command shows all mappings in local? ARP cache nslookup ; NameServer lookup; look up Ip addresses given server name, does other DNS related stuff too on any win machine netdiag ; Network Diagnosis; network info + tests passed or failed dcdiag ; Domain Controller diagnosis dnscmd /info ; Domain Name Server information netstat -an ; Port listing of open and connected network ports