Local SAP, LLC Profile Name, T2 Rx Ack Timer | EXP Computer S200

LLC2 Local Termination

Local SAP

Range:	01 to FE (hexadecimal)

Default:	04

Description:	This SAP must match the source SAP of the frame received from
	the LAN port for the session to be spoofed.
	If you are using Local Termination Autolearn, specify the remote
	Host SAP for the local MAC.

Boot Type:	LLC LT Station

LLC Profile Name

Range:	0 to 8 (alphanumeric, space blanks field)

Default:	(Blank)

Description:	Local Term Station Table references this parameter for the T1, T2,
	TI, N2, N3, and TW values. If no profile name is specified, then
	default values are used.

Boot Type:	LLC LT Station

Configuring the LT These parameters make up the LT WAN Parameters Table.

WAN Parameters

T1Reply Timer

Range:	1 to 25 (seconds)

Default:	3

Description:	This Ack timer is used by a station to detect a failure of the remote
	station to acknowledge an outstanding I frame or supervisory
	frame with the pole bit set to 1.

Boot Type:	LLC LT WAN Parameters.

T2 Rx Ack Timer

Range:	1 to 255 (tenths of seconds)

Default:	1

Description:	The Receive Ack timer is used by a station to determine how long
	it will withhold acknowledgment of a frame from the remote
	station that requires acknowledgment. This is a method of
	reducing the amount of acknowledgments generated by a link
	station. When this timer expires, the link station should
	immediately send an acknowledgment for all received frames not
	yet acknowledged.

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Bridging

Image 112

Contents

3Com Corporation Restricted Rights Notification for U.S. Government Users Restricted Rights Legend Proprietary Material Page Solutions OverviewFunctionality Multiple LANs Translational BridgingNo Local Bridging Transparent This Manual Topic This Notice Topic Bridging Features and Capabilities SwitchesIntroduction Bridging Primer Ethernet LAN Example Ethernet BridgeOperation WAN application, but you can also bridge across an X.25 WAN Mixed LAN Bridging MAC Addressing LLC2 Local Termination LLC2 LocalTermination LT Example Autolearn for Local Termination NetBIOS Name FilteringMac Address Filtering What Is It? Automatic Manual Spanning Tree Support Spanning Tree Protocol Dual Ethernet LANs Across a WAN Basic Remote Bridging ExamplesWAN or Permanent Virtual Circuit PVC for Frame Relay Example of Bridges in an SVC Arrangement Bridge ConnectionsLAN Interface Support Bridging Setting Up WAN Operation for Bridging Interface Connections Between WAN and LAN Setting Up WAN Operation for Bridging Configure Bridge Parameters ParametersThese parameters make up the Bridge Parameter Record Maximum Number of Bridge Links Bad Hello Timeout Stpe ControlAUTO, MAN MAN Aging Period used for Ethernet only Learn Only Period used for Ethernet onlyBridge WAN Data Priority used for Ethernet only Bridged Protocols Parameters control the characteristics of this connection Bridge Link ParametersBridge links as links to the networks attached to it Bridge Link These parameters make up the Bridge Link Record Entry NumberBridgeType SR, TB, Bothsrandtb Hop Count Limit Largest Frame SizeMAC Address Filter Action NONE, PASS, Block Protocol Filter Action Netbios Name Filter ActionStpe Link State Link Mode NORMAL,RFC1294, TransNormal Virtual Ring Number LAN Connection Table Over the WANLAN Connection Table Parameters LAN Forwarder Type ROUT, BRID, BroutRout LAN Connection Type Encapsulation Type CodexAutocall Mnemonic Lcon Queue Limit Billing Records OFF, onOFF Traffic Priority Where bridging is done remotely across a WAN Limiting Bridge Frame SizesOverview Transmission times for large frames become significant Standard Frame SizesMaximum frame size Max Frame Size Line Speed Range kbps Configuring Translational Bridging Translational Bridging Example Bridge Frame Handling Configuring Source Route Bridging Operation ConfiguringNode for SRB Individual Bridge Bridging Connecting a Station to a Server in Source Route Bridging ProcedureLAN 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 Step Action Result/Description Then Learning Transparent Bridging for Ethernet LANsForwarder LAN link WAN link Link error Forwarder ExampleStatistics Filtering Accelerator LAN/WAN Handlers HardwareHardware Accelerator Functions Forwarder Functions Forwarder Initialization Learn Only Period Aging Forwarder Database and Spanning Tree Using Filters Multicast Link Frame is droppedList, the frame is dropped Control menu located in the Main menu Transparent Bridge Configuration Parameters TB ForwardingLocal MAC Address Bridge Link Number What is It? How Filtering is Used Bridge Filtering MAC Address Filtering Parameter Action Parameter Parameter Action Value MAC Filtering Process Mac Filtering Process Incoming and Outgoing Frames Example of a Frame Passing on a Bridge Link How To Configure Example Configuring the Bridge Link RecordMAC Address Filtering Examples First Example Configuring the MAC Address Filter Table Identifying Address Links for MAC Addressing Why it is ImportantAddress Links MAC Wildcard Filtering Series Switch SupportFiltering works Broadcast frames in the LAN network Configuring the MAC Address Filter TableCategories These parameters make up the MAC Address Filter Table Incoming Source Address Link ActionPASS, BLOCK, PASSLIST, Blocklist Pass Outgoing Source Address Link Action Incoming Destination Address Link Action Outgoing Destination Address Link Action List of Links Protocol Filtering Protocol Filter These parameters make up the Protocol Filter Table Record Protocol Type Protocol SAP hex valueProtocol OUI/IP hex value Protocol Value Incoming Protocol Link Action Outgoing Protocol Link Action Dsap Values Parameter Actions Broadcasts to and from the SVR* name pattern NetBIOS Name FilteringTransparent Bridging Checking NetBIOS Forcing a LocalDomain With Filters Configuring NetBIOS Name Filtering How to ConfigureNetBIOS Name Filtering Step Action Select Configure Configure Step Action ResultEntry Number 1 appears Bridge Bridge Link Configure NetBIOS NetBIOS Name Filter TableBridge -NetBIOS Name Filter Name Filter Table String Type Typical FilteringAscii Incoming NetBIOS Name Link Action Incoming NetBIOS Name List of Links Outgoing NetBIOS Name Link Action Outgoing NetBIOS Name List of LInks NetBIOS Name Filtering Statistics NetBIOS broadcasts filtered on the linkEach bridge link Check Detailed NetBIOS Packet Formats IBM NetBIOS Formats When to Use NetBIOS Name FilteringAll of the following are true Either one of the following is true Configuration Stpe Control= Auto Stpe Control = Manual Menu Spanning Tree Protocol Entity StpeSpanning Tree Tree Bridge Links Spanning Tree Protocol Entity Stpe Example of a Stpe Parameter Setting ConsiderationsBridge Network Bridge ID equals Bridge Priority Value in hex + MAC Address Setting the Root Bridge Spanning TreeDetermining Root Links Designated Links Type of Network Speed Stpe Path Cost Consider NatureExpected Number SVCs Two Bridge Links Between B3 and B4 Spanning Tree Protocol Entity Stpe Spanning Tree Timers Timer ParametersHello Timer Max Age Other Considerations Bridge Forward Delay Timer Message Events in Network Spanning Tree Protocol Entity Stpe Bridges can adjust to the change Aging TimerLocation and forwards packets to it properly Preventing session timeouts in a Bridging application LLC2 Local Termination Well as network delays Terminal session, causingBefore Local After Local Topologies SupportedImproper LT LLC Protocol LLC Frame Description LLC2 Frame Description Proper LT configurationType Name Description Local Termination spoofs Local Termination does not spoof Bridging 105 Configuring Local Termination Local Termination Step Boot Type LLC LT StationStation Table Entry Number WAN Parameters T1Reply Timer T2 Rx Ack TimerLocal SAP LLC Profile Name Boot Type LLC LT WAN Parameters Ti Inactivity TimerN3 ACK Delay Count N2 Retry Count Configuration Entry Number Tx Window SizeLCC LT WAN Data Priority HIGH, MEDIUM, LOW T1 Reply Timer 112 Bridging Deleting LT Configuration Records Mixed LAN Operation 27x switch, as shown in FigureMixed LAN Environment Limitations Select Configure Bridge Bridge Link Parameters menuBridge Link Parameters from CTP Main menu, to activate Bridge link Bothsrandtb System powerup Dual LAN Ethernet Routing SupportedDual Ethernet LAN Cmem For Details on Parameters LAN Server Subsystem Alarms Configuring the LSS Record Example of LCCRecord Virtual Port’s MAC Address ENABLE, Disable DisableVirtual Bridge ID Path Trace Control Bridge Statistics Statistics Menu screen Spanning Tree Statistics Stpe StatusStatus report Term Description Disabled The Stpe is disabled. If Stpe Control StateAre Parameter is MAN Detailed Bridge Link Statistics Detailed Bridge Link Statistics First Screen Terms RIF Bridge Link Filter Summary Link FilterSummary Description Bridging 131 Transparent Bridge Forwarding Table Statistics Stats ExampleStats Descriptions Shown in Figure Bridging 133 Transparent Bridge Detailed Bridge Link Statistics Terms-Transparent Bridge Second Frame Totals This is a count of the number of frames FF-FF-FF-FF-FF-FFReceived/transmitted of all types on this link Statistics Menu LAN Connection StatisticsDetailed LAN Connection Statistics Detailed LAN Connection Statistics Second Explains why the last call was cleared Last clear diagnostic code This is the diagnostic codeConnection and explains why the call was cleared SVCs. The possible states are Blank for PVCs blank Bridging 139 Example of LAN shows the LAN Connection Summary Statistics Connection Summary Statistics LLC2 LT Session Summary Statistics Heading DescriptionSAP Remote MAC Addr Heading LLC2 LT Detailed Session Statistics Session Statistics Routing information field used in all frames transmitted Last Statistics Last time statistics were reset ResetField, ring number, and bridge number information Heading Description Local Station Session Summary Heading Description Remote Spoofer Session Summary Reset Statistics 148 Bridging Technical Support Access by Analog Modem 3ComFacts Automated Fax ServiceAccess by Digital Modem Country Data Rate Telephone Number 3Com Support fromCountry Telephone Number Country Telephone Number Fax Number Index Numerics LAN OUI URL A-1 Index-5