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Chapter 16
Connecting LANs,Backbone Networks,
and Virtual LANs
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16.1 Connecting Devices16.1 Connecting Devices
Repeaters
Hubs
Bridges
Two-Layer Switches
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Figure 16.1 Connecting devices
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Figure 16.2 Repeater
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A repeater connects segments of a LAN.
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A repeater forwards every frame; it has no filtering capability.
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A repeater is a regenerator, not an amplifier.
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Figure 16.3 Function of a repeater
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Figure 16.4 Hubs
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A bridge has a table used in filtering decisions.
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Figure 16.5 Bridge
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A bridge does not change the physical (MAC) addresses in a frame.
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Figure 16.6 Learning bridge
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Figure 16.7 Loop problem
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Figure 16.8 Prior to spanning tree application
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Figure 16.9 Applying spanning tree
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Figure 16.10 Forwarding ports and blocking ports
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16.2 Backbone Networks16.2 Backbone Networks
Bus Backbone
Star Backbone
Connecting Remote LANs
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In a bus backbone, the topology of the backbone is a bus.
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Figure 16.11 Bus backbone
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In a star backbone, the topology of the backbone is a star; the backbone is
just one switch.
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Figure 16.12 Star backbone
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Figure 16.13 Connecting remote LANs
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A point-to-point link acts as a LAN in a remote backbone connected by
remote bridges.
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16.3 Virtual LANs16.3 Virtual LANs
Membership
Configuration
IEEE Standard
Advantages
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Figure 16.14 A switch connecting three LANs
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Figure 16.15 A switch using VLAN software
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Figure 16.16 Two switches in a backbone using VLAN software
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VLANs create broadcast domains.
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