Avaya
Avaya is an American multinational technology company headquartered in Durham, North Carolina, that specializes in business communications, specifically unified communications (UC), contact center (CC), and services.
Cisco
Cisco Systems, Inc. is an American multinational technology conglomerate headquartered in San Jose, California, in the center of Silicon Valley. Cisco develops, manufactures, and sells networking hardware, software, telecommunications equipment, and other high-technology services and products.
Panasonic
Panasonic Corporation, formerly known as the Matsushita Electric Industrial Co., Ltd., founded by K?nosuke Matsushita in 1918 as a lightbulb socket manufacturer, is a major Japanese multinational electronics company, headquartered in Kadoma, Osaka.
Grandstream
Founded in 2002, Grandstream Networks is a manufacturer of IP voice and video communications equipment, video surveillance, gateways and analog telephone adapters, and Asterisk-based IP-PBX appliances.
snom
Snom Technology GmbH is a German company which manufactures Voice over Internet Protocol telephones, based on the IETF standard Session Initiation Protocol.