| Type | Subsidiary |
|---|---|
| Industry | Computer networking |
| Founded | United States |
| Headquarters | United States |
| Parent | Cisco Systems |
Summa Four was a "dumb switch" telecommunications company based in Manchester, New Hampshire. It was acquired by Cisco Systems on July 28, 1998.
Cisco Systems sold mainly the VCO/4K Open Programmable Switch line, finally announced the end of sales for the VCO/4K Open Programmable Switch as of March 1, 2002. Cisco has entered into an agreement with Compro Technologies Inc.,a New Jersey, United States-based telephony application developer and services company, to offer worldwide support for this product line.