Cisco Systems

Cisco Systems, Inc. (NASDAQ: CSCO, SEHK: 4333), one of the most successful companies today, originally manufactured only enterprise routing equipment. These days, Cisco sells a variety of devices for both enterprises and telecommunications carriers. These include, but are not limited to:
Ethernet switches
Branch office routers and CPE (Customer Premises Equipment)
IP Telephony products such as IP PBXes (CallManager), VoIP gateways and IP phones
Network security devices such as Firewalls, VPN concentrators, Network and Host Intrusion Prevention and Software
Metro optical switching platforms
Large telco-class core and edge routers / MPLS switches
Carrier and enterprise ATM switches
Cable Modem Termination Systems (CMTSes)
DSL subscriber aggregation / concentration equipment
Remote access and universal gateways
Storage Area Network (SAN) switches and appliances
Network management software and appliances
Wireless
Home networking products (via the Linksys division)
Cisco's tag line is "The Worldwide Leader in Networking for the Internet"
Corporate history

The married couple Leonard Bosack and Sandra Lerner, who worked in computer operations staff at Stanford University, founded Cisco Systems in 1984. Bosack adapted multiple-protocol router software originally written by William Yeager, another staff employee who had begun the work years before Bosack arrived from the University of Pennsylvania, where Bosack had received his Bachelor's degree.
While Cisco was not the first company to develop and sell a router (a device that forwards computer traffic from one network to another), it did create the first commercially successful multi-protocol router to allow previously incompatible computers to communicate using different network protocols. As the Internet Protocol (IP) has become a standard, the importance of multi-protocol routing as a function has declined. Today, Cisco's largest routers are marketed to route primarily IP packets and MPLS frames.
In 1990 the company went public and was listed on the Nasdaq stock exchange. Bosack and Lerner walked away from the company with $170 million, and later divorced.
Using acquisitions, internal development and partnering with other companies Cisco has made inroads into many network equipment markets outside of routing, including Ethernet switching, remote access, branch office routers, ATM networking, security, IP telephony and others. In 2003, Cisco acquired Linksys, a popular manufacturer of computer networking hardware and positioned it as a leading brand for the home and the end user networking market (SOHO).
Cisco has set up "Cisco Networking Academies" in 150 countries aimed at teaching students to design and maintain computer networks.
Cisco provides certifications to professionals in the networking field. These include:
CCIE (Cisco Certified Internetwork Expert)
CCNP (Cisco Certified Network Professional)
CCDP (Cisco Certified Design Professional)
CCIP (Cisco Certified Internetwork Professional)
CCSP (Cisco Certified Security Professional)
CCVP (Cisco Certified Voice Professional)
CCNA (Cisco Certified Network Associate)
CCDA (Cisco Certified Design Associate)
The company has its corporate headquarters in San Jose, California.