Spanning Tree Protocol | EXP Computer S200 specification

Bridging Features and Capabilities

Spanning Tree Protocol

What Is It?

Automatic &

Manual Spanning

Tree Support

Spanning Tree Protocol reduces multiple bridge paths between LANs to a single path. Instead of a mesh network with several paths to a destination, the Spanning Tree Protocol remaps the network so that only one path is active for traffic between any source station and any destination station. The other paths block any frames between the LANs.

A spanning tree network eliminates parallel paths and traffic loops.

The PathBuilder S200 series switch implementation of the Spanning Tree Protocol Entity (SPTE) conforms to IEEE 802.ID specifications. Refer to the IEEE 802.ID specification for more detailed information on Spanning Tree Protocol operation.

PathBuilder S200 series switch support both automatic and manual spanning tree operations.

If you do not want to configure spanning tree operation yourself, you can use the automatic spanning tree creation option. Remember that a all bridges in your network must be configured to automatic spanning tree operation to allow for the spanning tree protocol to determine the spanning tree.

For More Details... See the“Spanning Tree Protocol Entity (STPE)” section on page 86.

Bridging

13

T0008-16F

Release 5.2M

Image 17

EXP Computer S200 manual Spanning Tree Protocol, What Is It? Automatic Manual Spanning Tree Support

Contents

3Com Corporation Restricted Rights Legend Restricted Rights Notification for U.S. Government Users Proprietary Material Page Overview SolutionsFunctionality Multiple LANs Bridging TranslationalNo Local Bridging Transparent This Manual Topic This Notice Topic Switches Bridging Features and CapabilitiesIntroduction Bridging Primer Ethernet LAN Ethernet Bridge ExampleOperation WAN application, but you can also bridge across an X.25 WAN Mixed LAN Bridging MAC Addressing LLC2 Local LLC2 Local TerminationTermination LT Example Autolearn for Local Termination Filtering NetBIOS NameMac Address Filtering Spanning Tree Protocol What Is It? Automatic Manual Spanning Tree Support Dual Ethernet LANs WAN or Permanent Virtual Circuit PVC for Frame Relay Basic Remote Bridging ExamplesAcross a WAN Example of Bridges in an SVC Arrangement Connections BridgeLAN Interface Support Bridging Interface Connections Between WAN and LAN Setting Up WAN Operation for Bridging Setting Up WAN Operation for Bridging Configure Parameters Bridge ParametersThese parameters make up the Bridge Parameter Record Maximum Number of Bridge Links Stpe Control Bad Hello TimeoutAUTO, MAN MAN Bridge WAN Data Priority used for Ethernet only Learn Only Period used for Ethernet onlyAging Period used for Ethernet only Bridged Protocols Bridge Link Parameters Parameters control the characteristics of this connectionBridge links as links to the networks attached to it Bridge Link Entry Number These parameters make up the Bridge Link RecordBridgeType SR, TB, Bothsrandtb Largest Frame Size Hop Count LimitMAC Address Filter Action NONE, PASS, Block Stpe Link State Netbios Name Filter ActionProtocol Filter Action NORMAL,RFC1294, Trans Link ModeNormal Virtual Ring Number Over the WAN LAN Connection TableLAN Connection Table Parameters ROUT, BRID, Brout LAN Forwarder TypeRout LAN Connection Type Codex Encapsulation TypeAutocall Mnemonic Lcon Queue Limit OFF, on Billing RecordsOFF Traffic Priority Limiting Bridge Frame Sizes Where bridging is done remotely across a WANOverview Transmission times for large frames become significant Sizes Standard FrameMaximum frame size Max Frame Size Line Speed Range kbps Configuring Translational Bridging Translational Bridging Example Bridge Frame Handling Configuring Configuring Source Route Bridging OperationNode for SRB Individual Bridge Bridging Procedure Connecting a Station to a Server in Source Route BridgingLAN for a Source Route Bridging operation Located on remote LAN CCC Figure Server’s Destination MAC Address Not on LAN AAA LAN Bridge Link WAN Adapter Transmits Each are Frame Across the WAN Server Responds with Specifically Routed Test Frame Then Step Action Result/Description Forwarder Transparent Bridging for Ethernet LANsLearning Forwarder Example LAN link WAN link Link errorStatistics Filtering Hardware Accelerator Functions HardwareAccelerator LAN/WAN Handlers Forwarder Functions Forwarder Initialization Aging Learn Only Period Forwarder Database and Spanning Tree Using Filters Frame is dropped Multicast LinkList, the frame is dropped Control menu located in the Main menu TB Forwarding Transparent Bridge Configuration ParametersLocal MAC Address Bridge Link Number Bridge Filtering What is It? How Filtering is Used Parameter Action MAC Address Filtering Parameter Action Value Parameter Process MAC Filtering Example of a Frame Passing on a Bridge Link Mac Filtering Process Incoming and Outgoing Frames Configuring the Bridge Link Record How To Configure ExampleMAC Address Filtering Examples First Example Configuring the MAC Address Filter Table Address Links Why it is ImportantIdentifying Address Links for MAC Addressing Filtering works Series Switch SupportMAC Wildcard Filtering Categories Configuring the MAC Address Filter TableBroadcast frames in the LAN network Incoming Source Address Link Action These parameters make up the MAC Address Filter TablePASS, BLOCK, PASSLIST, Blocklist Pass Incoming Destination Address Link Action Outgoing Source Address Link Action List of Links Outgoing Destination Address Link Action Protocol Filtering These parameters make up the Protocol Filter Table Record Protocol Filter Protocol SAP hex value Protocol TypeProtocol OUI/IP hex value Protocol Value Outgoing Protocol Link Action Incoming Protocol Link Action Dsap Values Parameter Actions Transparent Bridging NetBIOS Name FilteringBroadcasts to and from the SVR* name pattern Forcing a Local Checking NetBIOSDomain With Filters How to Configure Configuring NetBIOS Name FilteringNetBIOS Name Filtering Step Action Step Action Result Select Configure ConfigureEntry Number 1 appears Bridge Bridge Link NetBIOS Name Filter Table Configure NetBIOSBridge -NetBIOS Name Filter Name Filter Table Ascii Typical FilteringString Type Incoming NetBIOS Name List of Links Incoming NetBIOS Name Link Action Outgoing NetBIOS Name List of LInks Outgoing NetBIOS Name Link Action NetBIOS broadcasts filtered on the link NetBIOS Name Filtering StatisticsEach bridge link Check Detailed IBM NetBIOS Formats When to Use NetBIOS Name Filtering NetBIOS Packet FormatsAll of the following are true Either one of the following is true Spanning Tree Protocol Entity Stpe Configuration Stpe Control= Auto Stpe Control = Manual MenuSpanning Tree Tree Bridge Links Spanning Tree Protocol Entity Stpe Bridge Network Stpe Parameter Setting ConsiderationsExample of a Determining Root Links Designated Links Setting the Root Bridge Spanning TreeBridge ID equals Bridge Priority Value in hex + MAC Address Type of Network Speed Stpe Path Cost Nature ConsiderExpected Number SVCs Two Bridge Links Between B3 and B4 Spanning Tree Protocol Entity Stpe Timer Parameters Spanning Tree TimersHello Timer Max Age Considerations Other Message Events in Network Bridge Forward Delay Timer Spanning Tree Protocol Entity Stpe Location and forwards packets to it properly Aging TimerBridges can adjust to the change LLC2 Local Termination Preventing session timeouts in a Bridging application Terminal session, causing Well as network delaysBefore Local After Local Improper LT SupportedTopologies Type Name Description Proper LT configurationLLC Protocol LLC Frame Description LLC2 Frame Description Local Termination does not spoof Local Termination spoofs Bridging 105 Local Termination Configuring Local Termination Station Table Entry Number Boot Type LLC LT StationStep T2 Rx Ack Timer WAN Parameters T1Reply TimerLocal SAP LLC Profile Name Ti Inactivity Timer Boot Type LLC LT WAN ParametersN3 ACK Delay Count N2 Retry Count Tx Window Size Configuration Entry NumberLCC LT WAN Data Priority HIGH, MEDIUM, LOW T1 Reply Timer 112 Bridging Deleting LT Configuration Records Mixed LAN Environment Limitations 27x switch, as shown in FigureMixed LAN Operation Bridge Link Parameters menu Select Configure BridgeBridge Link Parameters from CTP Main menu, to activate Bridge link Bothsrandtb Dual LAN Ethernet System powerup Supported RoutingDual Ethernet LAN Cmem Parameters For Details on LAN Server Subsystem Alarms Example of LCC Configuring the LSS RecordRecord Virtual Port’s MAC Address Disable ENABLE, DisableVirtual Bridge ID Path Trace Control Statistics Menu screen Bridge Statistics Stpe Status Spanning Tree StatisticsStatus report Term Description State Disabled The Stpe is disabled. If Stpe ControlAre Parameter is MAN Detailed Bridge Link Statistics First Detailed Bridge Link Statistics Screen Terms RIF Link Filter Bridge Link Filter SummarySummary Description Bridging 131 Stats Example Transparent Bridge Forwarding Table StatisticsStats Descriptions Shown in Figure Bridging 133 Terms-Transparent Bridge Second Transparent Bridge Detailed Bridge Link Statistics Received/transmitted of all types on this link FF-FF-FF-FF-FF-FFFrame Totals This is a count of the number of frames Detailed LAN Connection Statistics LAN Connection StatisticsStatistics Menu Detailed LAN Connection Statistics Second Last clear diagnostic code This is the diagnostic code Explains why the last call was clearedConnection and explains why the call was cleared SVCs. The possible states are Blank for PVCs blank Bridging 139 Connection Summary Statistics Example of LAN shows the LAN Connection Summary Statistics Heading Description LLC2 LT Session Summary StatisticsSAP Remote MAC Addr Heading Session Statistics LLC2 LT Detailed Session Statistics Field, ring number, and bridge number information Last Statistics Last time statistics were reset ResetRouting information field used in all frames transmitted Heading Description Local Station Session Summary Heading Description Remote Spoofer Session Summary Reset Statistics 148 Bridging Technical Support 3ComFacts Automated Fax Service Access by Analog ModemAccess by Digital Modem Country Data Rate Telephone Number Country Telephone Number Support from3Com Country Telephone Number Fax Number Numerics Index LAN OUI URL A-1 Index-5