Switching in an Enterprise Network Introducing Routing and Switching in the Enterprise Chapter 3 Version 4.0 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 1
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. 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 2
Compare the Types of Switches Used in an Enterprise Network Switching and network segmentation Content addressable memory (CAM) Virtual circuits 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 3
Compare the Types of Switches Used in an Enterprise Network Hardware-based Layer 2 switching Software-based Layer-3 (multilayer) switching 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 4
Compare the Types of Switches Used in an Enterprise Network Store and forward switching Cut-through switching Fast-forward Fragment-free 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 5
Compare the Types of Switches Used in an Enterprise Network Switch physical security Switch access security 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 6
Explain How Spanning Tree Protocol Prevents Switching Loops Redundancy in network equipment Redundant network links Dangers of switching loops Broadcast storms 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 7
Explain How Spanning Tree Protocol Prevents Switching Loops Create a loop-free logical topology Potential loop detection and port blocking Redundancy without switching loops 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 8
Explain How Spanning Tree Protocol Prevents Switching Loops Determining a root bridge Bridge ID (BID) Root ports, designated ports, and blocked ports 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 9
Explain How Spanning Tree Protocol Prevents Switching Loops STP recalculations Minimizing downtime PortFast UplinkFast BackboneFast 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 10
Explain How Spanning Tree Protocol Prevents Switching Loops Spanning-tree verification commands 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 11
Explain How Spanning Tree Protocol Prevents Switching Loops Rapid Spanning Tree Protocol Discarding Active topology 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 12
Describe and Configure VLANs on a Cisco Switch Virtual LANs Logical networks Broadcast control Transparent to end-users 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 13
Describe and Configure VLANs on a Cisco Switch VLAN functions VLAN membership Static Dynamic 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 14
Describe and Configure VLANs on a Cisco Switch VLAN 1: management VLAN VLAN numbers and names Port assignment 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 15
Describe and Configure VLANs on a Cisco Switch VLAN verification commands Deleting a VLAN Removing a port from a VLAN 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 16
Describe and Configure VLANs on a Cisco Switch VLAN ID Frame tagging: IEEE 802.1Q 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 17
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 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 18
Describe and Configure Trunking and Inter- VLAN Routing Extending VLANs across switches Configuring a native VLAN 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 19
Describe and Configure Trunking and Inter- VLAN Routing Connectivity between different VLANs Subinterfaces Router-on-a-stick 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 20
Maintain VLAN Structure on an Enterprise Network VLAN Trunking Protocol (VTP) purpose and goals Management domain VTP modes: server, client, transparent VLAN database Configuration revision number 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 21
Maintain VLAN Structure on an Enterprise Network VTP messages Summary advertisements Subset advertisements Advertisement requests 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 22
Maintain VLAN Structure on an Enterprise Network Configuring VTP Verifying VTP configuration 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 23
Maintain VLAN Structure on an Enterprise Network VLANs and IP phones VLANs and wireless security 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 24
Maintain VLAN Structure on an Enterprise Network VLAN best practices VLAN security 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 25
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. 2006 Cisco Systems, Inc. All rights reserved. Cisco Public 26
2006 Cisco Systems, Inc. All rights reserved. Cisco Public 27