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Pertemuan 7 Introduction to LAN Switching and

Switch Operation

Discussion Topics

• 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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Discussion Topics con’t

• 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