Discovery Routing Switching Chapter3

8/14/2019 Discovery Routing Switching Chapter3

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2006 Cisco Systems, Inc. All rights reserved. Cisco PublicITE I Chapter 6 1

Switching in an

Enterprise Network

Introducing Routing and Switching in the Enterprise Chapter 3


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2006 Cisco Systems, Inc. All rights reserved. Cisco PublicITE 1 Chapter 6 2

Objectives

Compare the types of switches used in an enterprisenetwork.

Explain how Spanning Tree Protocol preventsswitching loops.

Describe and configure VLANs on a Cisco switch.

Describe and configure trunking and Inter-VLANrouting.

Maintain VLANs in an enterprise network.


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Compare the Types of Switches Used in anEnterprise Network

Switching and network segmentation

Content addressable memory (CAM)

Virtual circuits


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Hardware-based Layer 2 switching

Software-based Layer-3 (multilayer) switching


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Store and forward switching

Cut-through switching

Fast-forward

Fragment-free


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Switch physical security

Switch access security


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Explain How Spanning Tree Protocol PreventsSwitching Loops

Redundancy in network equipment

Redundant network links

Dangers of switching loops

Broadcast storms




Create a loop-free logical topology

Potential loop detection and port blocking

Redundancy without switching loops




Determining a root bridge

Bridge ID (BID)

Root ports, designated ports, and blocked ports




STP recalculations

Minimizing downtime

PortFast

UplinkFastBackboneFast




Spanning-tree verification commands




Rapid Spanning Tree Protocol

Discarding

Active topology



Describe and Configure VLANs on a CiscoSwitch

Virtual LANs

Logical networks

Broadcast control

Transparent to end-users




VLAN functions

VLAN membership

Static

Dynamic




VLAN 1: management VLAN

VLAN numbers and names

Port assignment




VLAN verification commands

Deleting a VLAN

Removing a port from a VLAN




VLAN ID

Frame tagging: IEEE 802.1Q



Describe and Configure Trunking and Inter-VLAN Routing

Trunk port characteristics

Point-to-point link

Carry multiple-VLAN traffic over single link

Support for frame tagging Trunk modes



Extending VLANs across switches

Configuring a native VLAN




Connectivity between different VLANs

Subinterfaces

Router-on-a-stick




VLAN Trunking Protocol (VTP) purpose and goals

Management domain

VTP modes: server, client, transparent

VLAN database

Configuration revision number

Maintain VLAN Structure on an EnterpriseNetwork




VTP messages

Summary advertisements

Subset advertisements

Advertisement requests



Configuring VTP

Verifying VTP configuration




VLANs and IP phones

VLANs and wireless security



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VLAN best practices

VLAN security



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Summary

Switches forward traffic using store and forward or cut-throughtechniques

Basic security features should be applied to switches

A VLAN is a way to group hosts on the same logical network eventhough they may be physically separated

Frame tagging allows a switch to identify the source VLAN of anEthernet frame.

A Layer 3 device is needed to move traffic between differentVLANs.

Subinterfaces allow router interfaces to support multiple VLANs.

VLAN Trunking Protocol provides centralized control, distributionand maintenance of VLANs.


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Documents

Discovery Routing Switching Chapter3