Switching in an Enterprise Network - cnacad.com Discovery/Chapter 3/Chapter_3_Overview.pdf ·...
Transcript of Switching in an Enterprise Network - cnacad.com Discovery/Chapter 3/Chapter_3_Overview.pdf ·...
© 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 1Version 4.0
Switching in an Enterprise Network
Introducing Routing and Switching in the Enterprise – Chapter 3
© 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 2
Objectives
Compare the types of switches used in an enterprise network.
Explain how Spanning Tree Protocol prevents switching loops.
Describe and configure VLANs on a Cisco switch.
Describe and configure trunking and Inter-VLAN routing.
Maintain VLANs in an enterprise network.
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Compare the Types of Switches Used in an Enterprise Network
Switching and network segmentation
Content addressable memory (CAM)
Virtual circuits
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Compare the Types of Switches Used in an Enterprise Network
Hardware-based Layer 2 switching
Software-based Layer-3 (multilayer) switching
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Compare the Types of Switches Used in an Enterprise Network
Store and forward switching
Cut-through switching
Fast-forwardFragment-free
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Compare the Types of Switches Used in an Enterprise Network
Switch physical security
Switch access security
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Explain How Spanning Tree Protocol Prevents Switching Loops
Redundancy in network equipment
Redundant network links
Dangers of switching loops
Broadcast storms
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Explain How Spanning Tree Protocol Prevents Switching Loops
Create a loop-free logical topology
Potential loop detection and port blocking
Redundancy without switching loops
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Explain How Spanning Tree Protocol Prevents Switching Loops
Determining a root bridge
Bridge ID (BID)
Root ports, designated ports, and blocked ports
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Explain How Spanning Tree Protocol Prevents Switching Loops
STP recalculations
Minimizing downtime
PortFastUplinkFastBackboneFast
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Explain How Spanning Tree Protocol Prevents Switching Loops
Spanning-tree verification commands
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Explain How Spanning Tree Protocol Prevents Switching Loops
Rapid Spanning Tree Protocol
Discarding
Active topology
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Describe and Configure VLANs on a Cisco Switch
Virtual LANs
Logical networks
Broadcast control
Transparent to end-users
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Describe and Configure VLANs on a Cisco Switch
VLAN functions
VLAN membership
StaticDynamic
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Describe and Configure VLANs on a Cisco Switch
VLAN 1: management VLAN
VLAN numbers and names
Port assignment
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Describe and Configure VLANs on a Cisco Switch
VLAN verification commands
Deleting a VLAN
Removing a port from a VLAN
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Describe and Configure VLANs on a Cisco Switch
VLAN ID
Frame tagging: IEEE 802.1Q
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Describe and Configure Trunking and Inter- VLAN Routing
Trunk port characteristicsPoint-to-point linkCarry multiple-VLAN traffic over single link
Support for frame tagging
Trunk modes
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Extending VLANs across switches
Configuring a native VLAN
Describe and Configure Trunking and Inter- VLAN Routing
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Connectivity between different VLANs
Subinterfaces
Router-on-a-stick
Describe and Configure Trunking and Inter- VLAN Routing
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VLAN Trunking Protocol (VTP) purpose and goals
Management domain
VTP modes: server, client, transparent
VLAN database
Configuration revision number
Maintain VLAN Structure on an Enterprise Network
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Maintain VLAN Structure on an Enterprise Network
VTP messages
Summary advertisementsSubset advertisementsAdvertisement requests
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Configuring VTP
Verifying VTP configuration
Maintain VLAN Structure on an Enterprise Network
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VLANs and IP phones
VLANs and wireless security
Maintain VLAN Structure on an Enterprise Network
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VLAN best practices
VLAN security
Maintain VLAN Structure on an Enterprise Network
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Summary
Switches forward traffic using store and forward or cut-through techniques
Basic security features should be applied to switches
A VLAN is a way to group hosts on the same logical network even though they may be physically separated
Frame tagging allows a switch to identify the source VLAN of an Ethernet frame.
A Layer 3 device is needed to move traffic between different VLANs.
Subinterfaces allow router interfaces to support multiple VLANs.
VLAN Trunking Protocol provides centralized control, distribution and maintenance of VLANs.