D-Link DES-3250TG User Manual page 57

DES-3250TG Layer 2 Fast Ethernet Switch User's Guide
Figure 5- 7. 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
products from the same vendor) may communicate in
completely different ways. As long as peers can communicate
and interoperate, this has no impact on the functioning of the
network.
The communication between layers within a given protocol
stack can be both different from a second stack and
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