D-Link DES-3326 User Manual page 101

24-port NWay Ethernet Switch User's Guide
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 5-11. The Protocol Stack
Between two protocol stacks, members of the same layer are
known as peers and communicate by well-known (open and
published) protocols. Within a protocol stack, adjacent layers
communicate by an internal interface. This interface is usually
not publicly documented and is frequently proprietary. It has
some of the same characteristics of a protocol and two stacks
from the same software vendor may communicate in the same
way. Two stacks from different software vendors (or different
Switch Management and Operating Concepts
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