Inside Cisco IOS Software Architecture (CCIE Professional Development)

Chapter 7. The Cisco Gigabit Switch Router: 12000

This chapter covers the following key topics:

• Hardware architecture of the Cisco 12000 series routers

• Packet switching paths on the Cisco 12000 series routers

When businesses began seeing the value of the Internet in the early 1990s, an explosion in growth began that eventually took its toll on the Internet's backbone routers—mostly Cisco 7500s. The traffic explosion was paralleled by an increasing demand for reliability, as people began using the World Wide Web and e-mail as ways of doing business.

To meet these traffic and reliability demands, Cisco developed the Gigabit Switch Router (GSR)—the Cisco 12000 series.