BSCI Exam Cram™ 2 (Exam 642-801)

IS-IS Networks and Interfaces

As a CCNA, you are well aware of the ISO OSI networking structure. However, a fundamental distinction must be made at the outset of this chapter. The ISO developed an Open Systems Interconnection (OSI) networking suite that consists of two major components. The first piece is the familiar and often-memorized OSI reference model, which is an abstract network construct represented by a seven-layered model. The second component is the OSI protocol suite, which is a collection of standard networking protocols that includes CLNP and ES-IS, among others, which are covered in this chapter. We are concerned with the OSI Network and Transport layers and their relationship to OSI protocols and services that function at these ...