Cisco Systems BC-109 manual LNM Linking to a Source-Route Bridge on Each Local Ring

Page 19

Configure LNM Support

Figure 51 LNM Linking to a Source-Route Bridge on Each Local Ring

Token

Ring

PC running

LNM

SRB B

	Token	SRB A	Token	SRB C	WAN	SRB D
	Ring		Ring

Token

Ring

Token

Ring

S1113a

If LNM requires information about a station somewhere on a Token Ring, it uses a proprietary IBM protocol to query to one of the source-route bridges connected to that ring. If the bridge can provide the requested information, it simply responds directly to LNM. If the bridge does not have the necessary information, it queries the station using a protocol published in the IEEE 802.5 specification. In either case, the bridge uses the proprietary protocol to send a valid response back to LNM, using the proprietary protocol.

As an analogy, consider a language translator who sits between a French-speaking diplomat and a German-speaking diplomat. If the French diplomat asks the translator a question in French for the German diplomat and the translator knows the answer, he or she simply responds without translating the original question into German. If the French diplomat asks a question the translator does not know how to answer, the translator must first translate the question to German, wait for the German diplomat to answer, and then translate the answer back to French.

Similarly, if LNM queries a source-route bridge in the proprietary protocol and the bridge knows the answer, it responds directly using the same protocol. If the bridge does not know the answer, it must first translate the question to the IEEE 802.5 protocol, query the station on the ring, and then translate the response back to the proprietary protocol to send to LNM.

Figure 52 illustrates requests from the LNM originating in an IBM proprietary protocol and then translated into IEEE 802.5 MAC-level frames.

Configuring Source-Route Bridging BC-127

Image 19

Contents SRB Configuration Task List Configuring Source-Route BridgingConfigure a Dual-Port Bridge Configure Source-Route BridgingMultiple Dual-Port Bridges Configure a Multiport Bridge Using a Virtual RingSource-bridge ring-group ring-group Define a Ring Group in SRB ContextNo source-bridge ring-group ring-group Source-bridge route-cache cbus Configure SRB over FddiEnable SRB and Assign a Ring Group to an Interface Interface fddi slot/portConfigure SRB over Frame Relay Configure Fast-Switching SRB over FddiEnable the Automatic Spanning-Tree Function Limit the Maximum SRB Hops Enable Use of the RIF Configure Bridging of Routed ProtocolsConfigure the RIF Timeout Interval Configure a Static RIF EntryOverview of SR/TLB Following notes and caveats apply to all uses of SR/TLB No source-bridge transparent ring-group fastswitch Enable Bridging between Transparent Bridging and SRBDisable Fast-Switched SR/TLB Enable Translation Compatibility with IBM 8209 BridgesSource-bridge sap-80d5 dsap Enable Token Ring LLC2-to-Ethernet ConversionEnable 0x80d5 Processing Enable Standard Token Ring LLC2-to-Ethernet LLC2 ConversionConfigure NetBIOS Support Source-bridge proxy-netbios-only Specify Timeout and Enable NetBIOS Name CachingSpecify Dead-Time Intervals for NetBIOS Packets Configure the NetBIOS Cache Name LengthEnable NetBIOS Proxying Create Static Entries in the NetBIOS Name CacheNetbios name-cache query-timeout seconds Configure LNM SupportNetbios name-cache recognized-timeout seconds LNM Linking to a Source-Route Bridge on Each Local Ring LAN Network Manager Monitoring and Translating How a Router Works with LNMDisable LNM Functionality Enable Other LRMs to Change Router Parameters Disable Automatic Report Path Trace FunctionEnable LNM Servers Apply a Password to an LNM Reporting LinkChange Reporting Thresholds Monitor LNM Operation Change an LNM Reporting IntervalLnm softerr milliseconds Configure NetBIOS Access Filters Using Station Names Configure NetBIOS Access FiltersSecure the SRB Network Netbios input-access-filter bytes name Configure NetBIOS Access Filters Using a Byte OffsetNetbios access-list host name permit deny pattern Netbios access-list bytes name permit deny offsetNetbios output-access-filter bytes name Configure Administrative Filters for Token Ring TrafficFilter Frames by Protocol Type Filter Source Addresses Filter Frames by Vendor CodeFilter Destination Addresses Access Expression Example Optimize Access Expressions Configure Access ExpressionsTune the SRB Network Alter Access Lists Used in Access ExpressionsEnable or Disable the Source-Route Fast-Switching Cache Establish the Connection Timeout Interval Enable or Disable the SSEOptimize Explorer Processing Controlling Explorer Storms in Redundant Network Topologies Establish SRB Interoperability with TI MAC Firmware Configure Proxy ExplorersMac-address ieee-address Monitor and Maintain the SRB Network Report Spurious Frame-Copied ErrorsSource-bridge tcp-queue-max number SRB Configuration ExamplesBasic SRB with Spanning-Tree Explorers Example Dual-Port Source-Route Bridge ConfigurationSRB-Only Example Optimized Explorer Processing Configuration ExampleMultiport SRB Example SRB and Routing Certain Protocols ExampleSRB with Multiple Virtual Ring Groups Example Configuration for Router aRouter a SRB over Fddi Configuration ExamplesSRB over Fddi Fast-Switching Example Configuration for Router BFrad Using SRB over Frame Relay to Connect to a Cisco Router SRB over Frame Relay Configuration ExampleAdding a Static RIF Cache Entry Example Configuration of Router aConfiguration on Router B Configuration on Router CSR/TLB for a Simple Network Example Adding a Static RIF Cache Entry for a Two-Hop Path ExampleBC-154Bridging and IBM Networking Configuration Guide Example of a Bit-Swapped Address SR/TLB with Access Filtering ExampleSpecifying a Static Entry NetBIOS Support with a Static NetBIOS Cache Entry ExampleLNM for a Simple Network Example Wayfarer# show lnm configLNM for a More Complex Network Example NetBIOS Access Filters Example Filtering Bridged Token Ring Packets to IBM Machines Example Shows a router connecting four Token Rings Following access expression would result Creating Access Filters ExampleFast-Switching Example Access Filters ExampleAutonomous Switching Example