Cisco Systems BC-109 Creating Access Filters Example, Following access expression would result

Page 54

SRB Configuration Examples

access-list 203 permit 0xE0E0 0x0101 access-list 203 deny 0x0000 0xFFFF

Note that it is not necessary to check for an LSAP of 0xAAAA when filtering SNAP-encapsulated AppleTalk packets, because for source-route bridging, the use of type filters implies SNAP encapsulation.

Creating Access Filters Example

In math, you have the following:

3 x 4 + 2 = 14 but 3 x (4 + 2) = 18

Similarly, the following access expressions would return TRUE if lsap(201) and dmac(701) returned TRUE or if smac(702) returned TRUE:

lsap(201) & dmac(701) smac(702)

However, the following access expression would return TRUE only if lsap(201) returned TRUE and either of dmac(701) or smac(702) returned TRUE:

lsap(201) & (dmac(701) smac(702))

Referring to the earlier example, “An Example Using NetBIOS Access Filters,” we had the phrase:

“Pass the frame if it is NetBIOS, or if it is an SNA frame destined to address 0110.2222.3333.”

This phrase was converted to the simpler form of:

Pass if “NetBIOS or (SNA and destined to 0110.2222.3333).”

So, for the following configuration:

!Access list 201 passes NetBIOS frames (command or response) access-list 201 permit 0xF0F0 0x0001

access-list 202 permit 0x0404 0x0001 ! Permits SNA frames (command or response) access-list 202 permit 0x0004 0x0001 ! Permits SNA Explorers with NULL DSAP

!Access list 701 will permit the FEP MAC address

!of 0110.2222.3333

access-list 701 permit 0110.2222.3333

The following access expression would result:

access-expression in lsap(201) (lsap(202) & dmac(701))

BC-162Bridging and IBM Networking Configuration Guide

Image 54

Contents Configuring Source-Route Bridging SRB Configuration Task ListConfigure Source-Route Bridging Configure a Dual-Port BridgeConfigure a Multiport Bridge Using a Virtual Ring Multiple Dual-Port BridgesDefine a Ring Group in SRB Context Source-bridge ring-group ring-groupNo source-bridge ring-group ring-group Interface fddi slot/port Configure SRB over FddiEnable SRB and Assign a Ring Group to an Interface Source-bridge route-cache cbusConfigure Fast-Switching SRB over Fddi Configure SRB over Frame RelayEnable the Automatic Spanning-Tree Function Limit the Maximum SRB Hops Configure Bridging of Routed Protocols Enable Use of the RIFConfigure a Static RIF Entry Configure the RIF Timeout IntervalOverview of SR/TLB Following notes and caveats apply to all uses of SR/TLB Enable Translation Compatibility with IBM 8209 Bridges Enable Bridging between Transparent Bridging and SRBDisable Fast-Switched SR/TLB No source-bridge transparent ring-group fastswitchEnable Standard Token Ring LLC2-to-Ethernet LLC2 Conversion Enable Token Ring LLC2-to-Ethernet ConversionEnable 0x80d5 Processing Source-bridge sap-80d5 dsapConfigure NetBIOS Support Specify Timeout and Enable NetBIOS Name Caching Source-bridge proxy-netbios-onlyCreate Static Entries in the NetBIOS Name Cache Configure the NetBIOS Cache Name LengthEnable NetBIOS Proxying Specify Dead-Time Intervals for NetBIOS PacketsConfigure LNM Support Netbios name-cache query-timeout secondsNetbios name-cache recognized-timeout seconds LNM Linking to a Source-Route Bridge on Each Local Ring How a Router Works with LNM LAN Network Manager Monitoring and TranslatingDisable LNM Functionality Disable Automatic Report Path Trace Function Enable Other LRMs to Change Router ParametersApply a Password to an LNM Reporting Link Enable LNM ServersChange Reporting Thresholds Change an LNM Reporting Interval Monitor LNM OperationLnm softerr milliseconds Configure NetBIOS Access Filters Configure NetBIOS Access Filters Using Station NamesSecure the SRB Network Netbios access-list bytes name permit deny offset Configure NetBIOS Access Filters Using a Byte OffsetNetbios access-list host name permit deny pattern Netbios input-access-filter bytes nameConfigure Administrative Filters for Token Ring Traffic Netbios output-access-filter bytes nameFilter Frames by Protocol Type Filter Frames by Vendor Code Filter Source AddressesFilter Destination Addresses Access Expression Example Configure Access Expressions Optimize Access ExpressionsAlter Access Lists Used in Access Expressions Tune the SRB NetworkEnable or Disable the Source-Route Fast-Switching Cache Enable or Disable the SSE Establish the Connection Timeout IntervalOptimize Explorer Processing Controlling Explorer Storms in Redundant Network Topologies Configure Proxy Explorers Establish SRB Interoperability with TI MAC FirmwareMac-address ieee-address Report Spurious Frame-Copied Errors Monitor and Maintain the SRB NetworkSRB Configuration Examples Source-bridge tcp-queue-max numberDual-Port Source-Route Bridge Configuration Basic SRB with Spanning-Tree Explorers ExampleOptimized Explorer Processing Configuration Example SRB-Only ExampleSRB and Routing Certain Protocols Example Multiport SRB ExampleConfiguration for Router a SRB with Multiple Virtual Ring Groups ExampleConfiguration for Router B SRB over Fddi Configuration ExamplesSRB over Fddi Fast-Switching Example Router aSRB over Frame Relay Configuration Example Frad Using SRB over Frame Relay to Connect to a Cisco RouterConfiguration on Router C Configuration of Router aConfiguration on Router B Adding a Static RIF Cache Entry ExampleAdding a Static RIF Cache Entry for a Two-Hop Path Example SR/TLB for a Simple Network ExampleBC-154Bridging and IBM Networking Configuration Guide SR/TLB with Access Filtering Example Example of a Bit-Swapped AddressNetBIOS Support with a Static NetBIOS Cache Entry Example Specifying a Static EntryWayfarer# show lnm config LNM for a Simple Network ExampleLNM 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 Creating Access Filters Example Following access expression would resultAccess Filters Example Fast-Switching ExampleAutonomous Switching Example