Specifications

March 15, 2011 Page 1 of 20
Configuring VLANs
Thisdocumentprovidesthe followinginformationaboutconfiguringandmonitoring802.1Q
VLANsonEnterasys
®
N‐Series,S‐Series,K‐Series,andX‐Seriesmodularswitches,A‐Series,B‐
Series,C‐Seriesstackablefixedswitches,andD‐Series,G‐Series,andI‐Seriesstandalonefixed
switches.
What Is a VLAN?
AVLANisaVirtualLocalAreaNetwork—agroupingofnetworkdevicesthatislogically
segmentedbyfunctions,projectteams,orapplicationswithoutregardtothephysicallocat ionof
users.Forexample,severalendstationsmightbegroupedasadepartment,suchasEngineering
orFinance,havingthesame
attributes asaLAN,eventhoughtheyarenotallonthesamephys ical
LANsegment.
Toaccomplishthislogicalgrouping,thenetworkadministratoruses802.1QVLAN‐capable
switchingdevicesandassignseachswitchportinaparticulargrouptoaVLAN.PortsinaVLAN
sharebroadcasttrafficand
belongtothesamebroadcastdomain.BroadcasttrafficinoneVLANis
nottransmittedoutsidethatVLAN.
Why Would I Use VLANs in My Network?
VirtualLANsallowyoutopartitionnetworktrafficintologicalgroupsandcontroltheflowofthat
trafficthroughthenetwork.Oncethetrafficand,ineffect,theuserscreatingthetraffic,are
assignedtoaVLAN,thenbroadcastandmulticasttrafficiscontainedwithintheVLANandusers
canbe
allowedordeniedaccesstoanyofthenetwork’sresources.Also,youhavetheoptionof
configuringsomeoralloftheportsonadevicetoallowframesreceivedwithaparticularVLAN
IDandprotocoltobetransmittedonalimitednumberofports.Thiskeepsthetraffic
associated
withaparticularVLANandprotocolisolatedfromtheotherpartsofthenetwork.
For information about... Refer to page...
What Is a VLAN? 1
Why Would I Use VLANs in My Network? 1
How Do I Implement VLANs? 3
Understanding How VLANs Operate 3
VLAN Support on Enterasys Switches 6
Configuring VLANs 9
Terms and Definitions 18
Note: This document describes the configuration and operation of VLANs as defined by the IEEE
802.1Q standard and assumes that all devices being configured support that standard. No other
types of VLANs will be covered.