DES-3326S Layer 3 Fast Ethernet Switch User’s Guide
92 Switch Management and Operating Concepts
system or network, but must communicate and interoperate.
This requires very well-defined and well-known methods for
transferring messages and data. This is accomplished through
the protocol stack.
Protocol layering as simply a tool for visualizing the
organization of the necessary software and hardware in a
network. In this view, Layer 2 represents switching and Layer
3 represents routing. Protocol layering is actually a set of
guidelines used in writing programs and designing hardware
that delegate network functions and allow the layers to
communicate. How these layers communicate within a stack
(for example, within a given computer) is left to the operating
system programmers.
Figure 5-9. The Protocol Stack
