Enterasys Networks ELS10-27TX Appendix a Virtual Lans Vlans Vlans and Frame Tagging, Vlan Vlan Y

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APPENDIX A

VIRTUAL LANS (VLANS)

A.1 VLANS AND FRAME TAGGING

The ELS10-27TX supports IEEE 802.1Q-compliant virtual LANs (VLANs). This capability provides a highly efficient architecture for establishing VLANs within a network and for controlling broadcast/multicast traffic between workgroups.

Central to this capability is an explicit frame tagging approach for carrying VLAN information between interconnected network devices.

With frame tagging, a four-byte data tag field is appended to frames that cross the network. The tag identifies which VLAN the frame belongs to. The tag may be added to the frame by the end station itself or by a network device, such as a switch.

In the example in Figure A-1 below, the workstations attached to the top switch are members of the same two VLANs as the workstations attached to the bottom switch. The 802.1Q tags are used to carry VLAN information in the frames traveling between the two switches.

VLAN X

VLAN Y

EPIM100

ETHERNET SWITCH

STATUS

LINK

STATUS

LINK

STATUS

LINK

STATUS

LINK

STATUS

LINK

STATUS

LINK

STATUS

LINK

STATUS

LINK

STATUS

LINK

STATUS

LINK

STATUS

LINK

STATUS

LINK

10BASE-T/100BASE-TX

STATUS

LINK

STATUS

LINK

STATUS

LINK

STATUS

26

PORT STATUS MODE

ELS10-27TX

PWR

TX

ACT

FDX MON

RESET

COM

CPU

RX

COL

100 USR

2X

4X

6X

8X

10X

12X

14X

16X

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20X

22X

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27X

27

1

802.1Q tag added by Incoming port*

2

802.1Q tag carries

VLAN Identifier

ETHERNET SWITCH

PORT STATUS MODE

ELS10-27TX		PWR	STATUS
ELS10-27TX		PWR	TX ACT	FDX MON
RESET	COM	CPU	RX COL	100 USR

LINK

STATUS

LINK

STATUS

LINK

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LINK

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LINK

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LINK

STATUS

2X

4X

6X

8X

10X

12X

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LINK

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14X

16X

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10BASE-T/100BASE-TX

LINK

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LINK

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LINK

STATUS

25X

26X

27X

EPIM100

26

27

3

802.1Q used by

switch to determine VLAN, then stripped by forwarding port*

VLAN XVLAN Y

* Note	1	is true if it does not have a tag and is a hybrid port, or the port is an
access port.
* Note	3	is only stripped, if the hybrid port and the tag in the packet matches the

PVID or is an access port.

Figure A-1. Two-Switch VLAN Configuration

A-1

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Contents SmartSTACK Ethernet ELS10-27TX Supplement Page Page FCC Notice Cabletron SYSTEMS, INC Program License Agreement Page Page Page Cabletron Systems Limited Program License Agreement Viii Page Declaration of Conformity Contents Vlan MIB Objects Configuring Vlans Using SnmpXiii Appendix a Virtual Lans Vlans Index Configuring Workgroups Using LCMConfiguring Workgroups Using Snmp Workgroup MIB ObjectsAbout this Supplement Your email address Getting HelpDocument Conventions Document Title Part Number Related DocumentationProduct Overview Using Vlans on the ELS10-27TXIeee 802.1Q Standard Vlan Hybrid Ports 802.1Q Mode 802.1Q Mode on ELS10-27TXVlan Access Ports 802.1Q Mode Preserving Priority 3 802.1Q Trunk PortsNon-Preserving Priority Accessing Network Management Using VLANsDefault Port Vlan ID Switch ModeAssigning Ports to a Vlan Enable Gvrp Restricting VLANs 802.1Q ModeWorkgroups Virtual Workgroups will only operate in 802.1D modeInstallation and Management Default GatewayPage LCM Conventions OverviewSubset of LCM Commands LCM Command SummaryLCM Command Syntax Exit or Logout Basic LCM CommandsHelp EraseEnable Command Address Limit LCM CommandsRoute Command Port Command Port CommandEnhancements to LCM Commands Switch Command Trap Control Command ELS10-27vlan add 5-9 blue Vlan CommandPage Config Table Configuring Vlans Using Snmp OverviewStep Action Modifying, Creating and Deleting VLANsModifying a Vlan Deleting a Vlan Creating a VlanConfig Egress List Modifying a Config Egress List Entry Modifying, Creating or Deleting a Filter Gvrp Table Entry Filter Gvrp TableDeleting a Filter Creating a FilterCreating a Static MAC Entry Static MAC EntryDeleting a Static MAC Entry Vlan Version Number Bridge ConfigurationReset VlanReset Operating Mode VlanOperatingModeSyntax Octet String Size Gvrp Enable VlanGVRPEnableVlan VlanConfigVlan Access List VlanAccessListEntry VlanConfigEntry Configuration EntriesVlanConfigEntry VID VlanConfigVID Index VlanConfigIndexIP VlanConfigIP Ports VlanConfigPortsName VlanConfigName IP Mask VlanConfigIPMaskEstablish VlanConfigEstablish Status VlanConfigStatusDevice Entries Static Configured VlanNumConfiguredEntriesActive VlanNumActiveEntries Maximum Number VlanMaxNumEntries Configuration Table VlanConfigTableEgress Entry VlanConfigEgressEntry Egress Table Egress Table VlanConfigEgressTableIndex VlanEgressIndex VlanConfigEgressEntryList VlanEgressList VID VlanEgressVIDStatus VlanEgressStatus Gvrp VlanFilterGVRPTable Filter GvrpEntry VlanFilterGVRPEntry VlanFilterGVRPEntry VlanFilterGVRPIndexList VlanFilterGVRPList VID VlanFilterGVRPVIDEstablishVID VlanFilterGVRPEstablishVID Status VlanFilterGVRPStatusTable VlanStaticTable Static MAC Address EntriesEntry VlanStaticEntry VlanStaticEntry VID VlanStaticVIDPort VlanStaticPort MAC VlanStaticMACEstablish VlanStaticEstablish Page Chapter Configuring Workgroups Using LCM Overview Workgroup Default Workgroup Configuration ExamplesWorkgroup Superset Workgroups are only valid in 802.1D mode LCM Workgroup CommandsELS10-27workgroup omega Page Chapter Configuring Workgroups Using Snmp Overview Workgroup Configuration Procedures Configuring Workgroups Using Snmp Page Chapter Workgroup MIB Objects Overview Workgroups Using SnmpNext Number WorkGroupNextNumber MAX Count WorkGroupMaxCount Current Count WorkGroupCurrentCountTable WorkGroupTable Entry WorkGroupEntry Name WorkGroupName Number WorkGroupNumberType WorkGroupType Ports WorkGroupPortsVlan Vlan Y Appendix a Virtual Lans Vlans Vlans and Frame TaggingVlan ID ELS10-27TX Vlan ConfigurationPorts in Vlan Vlan Access PortsVlan Egress Figure A-2. Vlan Access Ports Numerics IndexSnmp Index