User`s guide
Table Of Contents
- Title
- Notice
- Contents
- Figures
- Tables
- About This Guide
- Introduction
- Local Management Requirements
- Accessing Local Management
- 3.1 Navigating Local Management Screens
- 3.2 Password Screen
- 3.3 Main Menu Screen
- 3.4 Module Selection Screen
- 3.5 Module Menu Screen
- 3.6 Overview of Security Methods
- 3.7 Security Menu Screen
- 3.8 Passwords Screen
- 3.9 Radius Configuration Screen
- 3.10 Name Services Configuration Screen
- 3.11 System Authentication Configuration Screen
- 3.12 EAP (Port) Configuration Screen
- 3.13 EAP Statistics Menu Screen
- 3.14 MAC Port Configuration Screen
- 3.15 MAC Supplicant Configuration Screen
- Chassis Menu Screens
- 4.1 Chassis Menu Screen
- 4.2 Chassis Configuration Screen
- 4.3 SNMP Configuration Menu Screen
- 4.4 SNMP Community Names Configuration Screen
- 4.5 SNMP Traps Configuration Screen
- 4.6 Chassis Environmental Information Screen
- 4.7 Redirect Configuration Menu Screen (Chassis)
- 4.8 Port Redirect Configuration Screen
- 4.9 VLAN Redirect Configuration Screen
- Module Configuration Menu Screens
- 5.1 Module Configuration Menu Screen
- 5.2 General Configuration Screen
- 5.2.1 Setting the IP Address
- 5.2.2 Setting the Subnet Mask
- 5.2.3 Setting the Default Gateway
- 5.2.4 Setting the TFTP Gateway IP Address
- 5.2.5 Setting the Module Name
- 5.2.6 Setting the Module Date
- 5.2.7 Setting the Module Time
- 5.2.8 Entering a New Screen Refresh Time
- 5.2.9 Setting the Screen Lockout Time
- 5.2.10 Configuring the COM Port
- 5.2.11 Clearing NVRAM
- 5.2.12 Enabling/Disabling IP Fragmentation
- 5.3 SNMP Configuration Menu Screen
- 5.4 SNMP Community Names Configuration Screen
- 5.5 SNMP Traps Configuration Screen
- 5.6 Access Control List Screen
- 5.7 System Resources Information Screen
- 5.8 FLASH Download Configuration Screen
- Port Configuration Menu Screens
- 6.1 Port Configuration Menu Screen
- 6.2 Ethernet Interface Configuration Screen
- 6.3 Ethernet Port Configuration Screen
- 6.4 HSIM/VHSIM Configuration Screen
- 6.5 Redirect Configuration Menu Screen
- 6.6 Port Redirect Configuration Screen
- 6.7 VLAN Redirect Configuration Screen
- 6.8 Link Aggregation Screen (802.3ad Main Menu Screen)
- 6.9 Broadcast Suppression Configuration Screen
- 802.1 Configuration Menu Screens
- 802.1Q VLAN Configuration Menu Screens
- 8.1 Summary of VLAN Local Management
- 8.2 802.1Q VLAN Configuration Menu Screen
- 8.3 Static VLAN Configuration Screen
- 8.4 Static VLAN Egress Configuration Screen
- 8.5 Current VLAN Configuration Screen
- 8.6 Current VLAN Egress Configuration Screen
- 8.7 VLAN Port Configuration Screen
- 8.8 VLAN Classification Configuration Screen
- 8.9 Protocol Port Configuration Screen
- 802.1p Configuration Menu Screens
- 9.1 802.1p Configuration Menu Screen
- 9.2 Port Priority Configuration Screen
- 9.3 Traffic Class Information Screen
- 9.4 Traffic Class Configuration Screen
- 9.5 Transmit Queues Configuration Screen
- 9.6 Priority Classification Configuration Screen
- 9.7 Protocol Port Configuration Screen
- 9.8 Rate Limiting Configuration Screen
- Layer 3 Extensions Menu Screens
- Module Statistics Menu Screens
- Network Tools Screens
- VLAN Operation and Network Applications
- 13.1 Defining VLANs
- 13.2 Types of VLANs
- 13.3 Benefits and Restrictions
- 13.4 VLAN Terms
- 13.5 VLAN Operation
- 13.6 Configuration Process
- 13.7 VLAN Switch Operation
- 13.8 VLAN Configuration
- 13.9 Summary of VLAN Local Management
- 13.10 Quick VLAN Walkthrough
- 13.11 Examples
- 13.12 Example 1, Single Switch Operation
- 13.13 Example 2, VLANs Across Multiple Switches
- 13.14 Example 3, Filtering Traffic According to a Layer 4 Classification Rule
- 13.15 Example 4, Securing Sensitive Information According to Subnet
- 13.16 Example 5, Using Dynamic Egress to Control Traffic
- 13.17 Example 6, Locking a MAC Address to a Port Using Classification Rules
- Generic Attribute Registration Protocol (GARP)
- About IGMP
- Index

Defining VLANs
13-2 VLAN Operation and Network Applications
13.1 DEFINING VLANs
A Virtual Local Area Network is a group of devices that function as a single Local Area Network
segment (broadcast domain). The devices that make up a particular VLAN may be widely
separated, both by geography and location in the network.
The creation of VLANs allows users located in separate areas or connected to separate ports to
belong to a single VLAN group. Users that are assigned to such a group will send and receive
broadcast and multicast traffic as though they were all connected to a common network.
VLAN-aware switches isolate broadcast, multicast, and unknown traffic received from VLAN
groups, so that traffic from stations in a VLAN are confined to that VLAN.
When stations are assigned to a VLAN, the performance of their network connection is not
changed. Stations connected to switched ports do not sacrifice the performance of the dedicated
switched link to participate in the VLAN. As a VLAN is not a physical location, but a
membership, the network switches determine VLAN membership by associating a VLAN with a
particular port or frame type.
Figure 13-1 shows a simple example of a port-based VLAN. Two buildings house the Sales and
Finance departments of a single company, and each building has its own internal network. The
stations in each building connect to a SmartSwitch in the basement. The two SmartSwitches are
connected to one another with a high speed link.