Cisco Systems is one of the leading suppliers of network management and equipment for the Internet. The company has been developing Internet protocol-based networking technologies since 1984. With more than 65,000 employees, it offers application networking services and interoperability systems. Cisco Systems interfaces and modules include broadband- and network-processing engines, as well as interface and line cards. The company also provides optical transponders, port adapters and universal serial bus cards. Its interoperability systems provide management response for emergencies and day-to-day operations across multiple agencies and jurisdictions. Cisco Systems also allows push-to-talk communications on radio handsets, networks, laptops, telephones and mobile phones. The company maintains a location in Lake Oswego, Ore.