Microsoft - Desktop, Server and productivity solutions.
Citrix - Desktop, Server and application virtualization solutions.
Symantec - Threat, Information and Website protection and security.
VMware - Desktop, Server, Storage vitualization and management
Sophos
HP
IBM
Dell
Cisco
Sonicwall
Palo Alto
Ring Central
Cogent
Comcast
Megapath
Birch
Century Link