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Pertemuan 7
Introduction to LAN Switching and
Switch Operation
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Discussion Topics
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LAN segmentation
LAN segmentation with bridges
LAN segmentation with routers
LAN segmentation with switches
Basic operations of a switch
Ethernet switch latency
Layer 2 and Layer 3 switching
Symmetric and asymmetric switching
Memory buffering
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Two switching methods
Functions of Ethernet switches
Frame transmission modes
How switches and bridges learn addresses
How switches and bridges filter frames
Why segment LANs?
Microsegmentation implementation
Switches and collision domains
Switches and broadcast domains
Communications between switches and workstations
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LAN Segmentation
Segmentation allows network congestion to
be significantly reduced within each
segment.
LAN Segmentation with
Bridges
LAN Segmentation with
Routers
LAN Segmentation with
Switches
LAN Switching Basics
LAN Switch Operation
Ethernet Switch Latency
Layer 2 Switching
Layer 3 Switching
Symmetric Switching
Asymmetric Switching
Memory Buffering
• Port-based memory buffering
– Packets are stored in queues that are linked to
specific incoming ports.
– It is possible for a single packet to block all other
packets because its destination port is busy (even if
the other packets could be delivered).
• Shared-memory buffering
– All packets use a common memory buffer.
– Packets in the buffer are then linked (mapped)
dynamically to the appropriate destination port.
– Helps balance between 10- and 100-Mbps ports.
Two Switching Methods
Store-and-forward
Cut-through
Functions of Ethernet
Switches
Frame Transmission Modes
Network Switch Using CAM
How Switches and Bridges
Filter Frames
Microsegmentation of the
Network
A switch employs “microsegmentation” to
reduce the collision domain on a LAN. The
switch does this by creating dedicated network
segments, or point-to-point connections.
Switches and Collision
Domains
The network area where frames originate and
collide is called the collision domain. All shared
media environments are collision domains.
Three Methods of Communication
Switches and Broadcast
Domains
• Broadcasting is when one transmitter tries
to reach all the receivers in the network.
The server station sends out one
message, and everyone on that segment
receives the message.
Communication Between
Switches and Workstations