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Functionality
Solutions
Overview
Multiple LANs
No Local Bridging
Translational
Bridging
Transparent
This Manual Topic
This Notice Topic
Introduction
Bridging Features and Capabilities
Switches
Bridging Primer
Ethernet LAN
Operation
Example
Ethernet Bridge
WAN application, but you can also bridge across an X.25 WAN
Mixed LAN Bridging
MAC Addressing
Termination
LLC2 Local Termination
LLC2 Local
LT Example
Autolearn for Local Termination
Mac Address
NetBIOS Name
Filtering
Filtering
What Is It? Automatic Manual Spanning Tree Support
Spanning Tree Protocol
Dual Ethernet LANs
WAN or Permanent Virtual Circuit PVC for Frame Relay
Basic Remote Bridging Examples
Across a WAN
Example of Bridges in an SVC Arrangement
LAN Interface
Bridge
Connections
Support
Bridging
Setting Up WAN Operation for Bridging
Interface Connections Between WAN and LAN
Setting Up WAN Operation for Bridging
Configure
These parameters make up the Bridge Parameter Record
Bridge Parameters
Parameters
Maximum Number of Bridge Links
AUTO, MAN
Bad Hello Timeout
Stpe Control
MAN
Bridge WAN Data Priority used for Ethernet only
Learn Only Period used for Ethernet only
Aging Period used for Ethernet only
Bridged Protocols
Bridge links as links to the networks attached to it
Parameters control the characteristics of this connection
Bridge Link Parameters
Bridge Link
BridgeType
These parameters make up the Bridge Link Record
Entry Number
SR, TB, Bothsrandtb
MAC Address Filter Action
Hop Count Limit
Largest Frame Size
NONE, PASS, Block
Stpe Link State
Netbios Name Filter Action
Protocol Filter Action
Normal
Link Mode
NORMAL,RFC1294, Trans
Virtual Ring Number
LAN Connection
LAN Connection Table
Over the WAN
Table Parameters
Rout
LAN Forwarder Type
ROUT, BRID, Brout
LAN Connection Type
Autocall Mnemonic
Encapsulation Type
Codex
Lcon Queue Limit
OFF
Billing Records
OFF, on
Traffic Priority
Overview
Where bridging is done remotely across a WAN
Limiting Bridge Frame Sizes
Transmission times for large frames become significant
Maximum frame size
Standard Frame
Sizes
Max Frame Size Line Speed Range kbps
Configuring Translational Bridging
Translational Bridging Example
Bridge Frame Handling
Node for SRB
Configuring Source Route Bridging Operation
Configuring
Individual Bridge
Bridging
LAN for a Source Route Bridging operation
Connecting a Station to a Server in Source Route Bridging
Procedure
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
Forwarder
Transparent Bridging for Ethernet LANs
Learning
Statistics
LAN link WAN link Link error
Forwarder Example
Filtering
Hardware Accelerator Functions
Hardware
Accelerator LAN/WAN Handlers
Forwarder Functions Forwarder Initialization
Learn Only Period
Aging
Forwarder Database and Spanning Tree
Using Filters
List, the frame is dropped
Multicast Link
Frame is dropped
Control menu located in the Main menu
Local MAC Address
Transparent Bridge Configuration Parameters
TB Forwarding
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
MAC Address Filtering Examples
How To Configure Example
Configuring the Bridge Link Record
First Example
Configuring the MAC Address Filter Table
Address Links
Why it is Important
Identifying Address Links for MAC Addressing
Filtering works
Series Switch Support
MAC Wildcard Filtering
Categories
Configuring the MAC Address Filter Table
Broadcast frames in the LAN network
PASS, BLOCK, PASSLIST, Blocklist
These parameters make up the MAC Address Filter Table
Incoming Source Address Link Action
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 OUI/IP hex value
Protocol Type
Protocol SAP hex value
Protocol Value
Incoming Protocol Link Action
Outgoing Protocol Link Action
Dsap Values
Parameter Actions
Transparent Bridging
NetBIOS Name Filtering
Broadcasts to and from the SVR* name pattern
Domain With
Checking NetBIOS
Forcing a Local
Filters
NetBIOS Name Filtering
Configuring NetBIOS Name Filtering
How to Configure
Step Action
Entry Number 1 appears
Select Configure Configure
Step Action Result
Bridge Bridge Link
Bridge -NetBIOS Name Filter
Configure NetBIOS
NetBIOS Name Filter Table
Name Filter Table
Ascii
Typical Filtering
String Type
Incoming NetBIOS Name Link Action
Incoming NetBIOS Name List of Links
Outgoing NetBIOS Name Link Action
Outgoing NetBIOS Name List of LInks
Each bridge link
NetBIOS Name Filtering Statistics
NetBIOS broadcasts filtered on the link
Check Detailed
All of the following are true
NetBIOS Packet Formats
IBM NetBIOS Formats When to Use NetBIOS Name Filtering
Either one of the following is true
Spanning Tree
Configuration Stpe Control= Auto Stpe Control = Manual Menu
Spanning Tree Protocol Entity Stpe
Tree
Bridge Links
Spanning Tree Protocol Entity Stpe
Bridge Network
Stpe Parameter Setting Considerations
Example of a
Determining Root Links Designated Links
Setting the Root Bridge Spanning Tree
Bridge ID equals Bridge Priority Value in hex + MAC Address
Type of Network Speed Stpe Path Cost
Expected Number
Consider
Nature
SVCs
Two Bridge Links Between B3 and B4
Spanning Tree Protocol Entity Stpe
Hello Timer
Spanning Tree Timers
Timer Parameters
Max Age
Other
Considerations
Bridge Forward Delay Timer
Message Events in Network
Spanning Tree Protocol Entity Stpe
Location and forwards packets to it properly
Aging Timer
Bridges can adjust to the change
Preventing session timeouts in a Bridging application
LLC2 Local Termination
Before Local
Well as network delays
Terminal session, causing
After Local
Improper LT
Supported
Topologies
Type Name Description
Proper LT configuration
LLC Protocol LLC Frame Description LLC2 Frame Description
Local Termination spoofs
Local Termination does not spoof
Bridging 105
Configuring Local Termination
Local Termination
Station Table Entry Number
Boot Type LLC LT Station
Step
Local SAP
WAN Parameters T1Reply Timer
T2 Rx Ack Timer
LLC Profile Name
N3 ACK Delay Count
Boot Type LLC LT WAN Parameters
Ti Inactivity Timer
N2 Retry Count
LCC LT WAN Data Priority
Configuration Entry Number
Tx Window Size
HIGH, MEDIUM, LOW
T1 Reply Timer
112 Bridging
Deleting LT Configuration Records
Mixed LAN Environment Limitations
27x switch, as shown in Figure
Mixed LAN Operation
Bridge Link Parameters from
Select Configure Bridge
Bridge Link Parameters menu
CTP Main menu, to activate Bridge link
Bothsrandtb
System powerup
Dual LAN Ethernet
Dual Ethernet LAN
Routing
Supported
Cmem
For Details on
Parameters
LAN Server Subsystem
Alarms
Record
Configuring the LSS Record
Example of LCC
Virtual Port’s MAC Address
Virtual Bridge ID
ENABLE, Disable
Disable
Path Trace Control
Bridge Statistics
Statistics Menu screen
Status report
Spanning Tree Statistics
Stpe Status
Term Description
Are
Disabled The Stpe is disabled. If Stpe Control
State
Parameter is MAN
Detailed Bridge Link Statistics
Detailed Bridge Link Statistics First
Screen Terms
RIF
Summary
Bridge Link Filter Summary
Link Filter
Description
Bridging 131
Stats Descriptions
Transparent Bridge Forwarding Table Statistics
Stats Example
Shown in Figure
Bridging 133
Transparent Bridge Detailed Bridge Link Statistics
Terms-Transparent Bridge Second
Received/transmitted of all types on this link
FF-FF-FF-FF-FF-FF
Frame Totals This is a count of the number of frames
Detailed LAN Connection Statistics
LAN Connection Statistics
Statistics Menu
Detailed LAN Connection Statistics Second
Connection and explains why the call was cleared
Explains why the last call was cleared
Last clear diagnostic code This is the diagnostic code
SVCs. The possible states are Blank for PVCs blank
Bridging 139
Example of LAN shows the LAN Connection Summary Statistics
Connection Summary Statistics
SAP
LLC2 LT Session Summary Statistics
Heading Description
Remote MAC Addr
Heading
LLC2 LT Detailed Session Statistics
Session Statistics
Field, ring number, and bridge number information
Last Statistics Last time statistics were reset Reset
Routing 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
Access by Digital Modem
Access by Analog Modem
3ComFacts Automated Fax Service
Country Data Rate Telephone Number
Country Telephone Number
Support from
3Com
Country Telephone Number Fax Number
Index
Numerics
LAN
OUI
URL A-1
Index-5