Technology White Paper
E T H E R N E T
S W I T C H I N G
T a b l e o f C o n t e n t s
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Shared vs. Switched . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-6
Switching Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6,7
Implementation Concerns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-10
Virtual LANs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10-12
Criteria for Selecting a Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12,13
High-Speed Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13,14
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
I n t r o d u c t i o n
Switching technology is increasing the efficiency and speed of networks. This technology
is making current systems more powerful, while at the same time facilitating the migration
to faster networks. Understanding this technology is important; only then can we design
and implement switched networks from the ground up.
Many networks are experiencing bandwidth shortages. There are several reasons for this
including an increase in traffic due to the sheer numbers of networked users, the amount
of data transported between client/server applications, and the inefficient traffic patterns
of some networks.
Switching directs network traffic in a very efficient manner—it sends information directly
from the port of origin to only its destination port. Switching increases network perfor-
mance, enhances flexibility and eases moves, adds and changes. Switching establishes a
direct line of communication between two ports and maintains multiple simultaneous
links between various ports. It proficiently manages network traffic by reducing media