Cabletron Systems SSIM-H2-02 manual TS Virtual Ports and Vlan Tagging, Virtual Port Restriction

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TS Virtual Ports and VLAN Tagging

Unlike ordinary Token Ring ports, Translational Switch (TS) ports can function as trunk ports, which means they can carry traffic belonging to all of the 63 VLANs it is possible to configure in the switch over the same physical cable connection.

Frames from different VLANs are distinguished by means of standard IEEE 802.1Q frame tags. A frame tag consists of a 2-byte Ethernet Frame Type of value 0x8100 (as described by standard P802.3ac) followed by a 2-byte Tag Control Information (TCI) field. It is inserted into the Ethernet frame after the frame header before transmission on the TS, and subsequently recognized and removed when the frame is received.

To identify the VLAN to which the frame belongs, the TCI field makes use of a 12- bit VLAN identifier that uniquely identifies the BRF. It also contains a 3 bit priority field (described in “FC Modification” on page 31).

Each TS port can be assigned to several CRFs, but there can be only one TS port per BRF/VLAN. A virtual port is created for each CRF to which the TS port is assigned. All virtual ports but one must be tagged (that is a single virtual port can be left untagged).

Note that a TS port with a single untagged virtual port is functionally equivalent to an ordinary Token Ring port. This is also the default configuration, with the virtual port in trcrf-default.

Virtual Port Restriction

A TS port can have only one virtual port in each VLAN. Otherwise it would not be possible to distinguish frames from two virtual ports in the same VLAN, since they would have the same VLAN identifier.

Ring Number Restriction

All CRFs in which a TS port has virtual ports must have the same ring number. The ring number is a per-port parameter and not a per-virtual-port parameter. If this were not the case, the meaning of the RIF would be ambiguous and would depend on the VLAN to which the frame was sent. It would thus be incomprehensible to equipment that does not interpret VLAN tags.

SSIM-H2-02 Fast Ethernet - Translational Switch SmartStack Interface Module Installation and User Guide

Configuration

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Contents Page Order Number 9032962-01 OC-7063 v .1 FCC Notice Vcci NoticeIndustry Canada Notice Declaration of Conformity Addendum IiiApplication of Council Directives 89/336/EEC 73/23/EEC Page Table of Contents Statistics List of Figures ViiList of Tables ViiiSSIM-H2-02 Switch SmartStack Interface Module IntroductionFeature Description This makes it possible to configure the device Part of the LAN switchSnmp is supported via the host processor Processor on the SmartStack STS16-20RMMIB Support FEUplink MIBInstallation Package ContentsInstallation Procedure Hardware Installation Removing the Expansion Slot CoverSoftware Installation Tftp DownloadSerial Download From the main menu, select Download→ UploadCabling LEDsPower-On Self Test Configuration Default ConfigurationConfiguration Introduction Ports, Port Groups and VLANsTS Virtual Ports and Vlan Tagging Virtual Port RestrictionRing Number Restriction Source Routed Switching SRS Operation Mode Source Routed Transparent Bridging SRT ModeBridging Modes Source Routed Bridging SRB Mode Ethernet CRF in SRB Bridging ModeRedundant Connections to Fast Ethernet Network Network ScenariosPreventing Frame Duplication Preventing Frame Looping Frame LoopingSpanning Tree Configuration Broken Ethernet CloudRedundant Connections to Fast Ethernet Network Page Technical Background STP Cost Modification General Guidelines Main Switch Menu Navigating Within the MenusConfiguration Overview Vlan Configuration Port Configuration TS PortsBRF Configuration Local Vlan Port ConfigurationVirtual Port Configuration StatusDisplay only. Shows the current status of the port Address Demand Aging LevelDefault Display only. Shows the current status of the virtual portYou can use only one value as MTU 1558 001Vlan Tagging Mode FC ModificationAddress Aging Time RIF Not Learn IntervalFrame Conversion Configuration IP Conversion StatusIP Conversion Parameters Change Default SR IP Ethernet FormatSets the format of IP frames on Ethernet Snap Frame in the Ieee 802.3 format with SnapEnable IP Fragmentation Novell Conversion StatusExplorer Frames Type TR MAC Address for IP MulticastsNovell Conversion Parameters Change Novell Frames ConversionNovell Token Ring Format Novell Ethernet FormatNetBios Conversion Status NetBios Conversion Parameters ChangeNetBios Frames Conversion IPX Address TranslationNetBios Token Ring Format NetBios Ethernet FormatSNA Conversion Status SNA Conversion Parameters ChangeSNA Ethernet Format Sets the format of SNA frames on EthernetOther Frames w/SNAP Conversion Status Other Frames w/SNAP Conversion Parameters ChangeOther Frames w/SNAP Frames Conversion Other Frames w/SNAP Token Ring FormatOther Frames w/o Snap Conversion Status Other Frames w/SNAP Ethernet FormatOther Frames w/o Snap Conversion Parameters Change Other Frames w/o Snap Frames ConversionOther Frames w/o Snap Token Ring Format Other Frames w/o Snap Ethernet FormatDual Home FEP Addresses Configuration Page Statistics Statistics Menu Port Status Port Statistics General StatisticsDiscarded Frames Table Filtered by Address Filter Table Filtered by Dsap FilterLocally Filtered Table Blocked Virtual PortTraffic Counters Error Counters Virtual Port Statistics Discarded Frames StatisticsVirtual Port State Frames ForwardedNetBios Inbound Translation errorsOther w/SNAP Other w/o SnapOutbound Translation Errors Outbound No TranslationFragmentation Error Generic w/o SnapGetting in Touch with Technical Support Your email addressPage Appendix A. Abbreviations Service Access Point Sub-Network Access ProtocolSource Route Switching Translational SwitchIndex Index-1Local Vlan port configuration Index-2710001816