Bridge Filtering

Forcing a Local

The NetBIOS Name Filtering feature can also force a local domain, or context, of a

Domain With

NetBIOS name. All branch offices, for example, may connect to an SNA gateway

NetBIOS Name

function in OS/2 by accessing a gateway local to the branch. Under normal bridging

Filters

conditions, you configure the SNA gateway NetBIOS server with a different name

 

 

for each branch office and every workstation to attach to the name for its branch

 

 

office.

 

 

With NetBIOS Name Filters, you can block the local service name (for example,

 

 

“SNA_GW”) on the WAN link so that NetBIOS broadcasts to and from that name

 

 

are not forwarded across to the internetwork.This feature lets the branches use the

 

 

same name for their local SNA service and you can configure all the workstations to

 

 

access the same local SNA name.

Wildcard Name

 

Name filter patterns may contain “wildcard” characters such as “?” that matches any

Patterns

character or “*” at the end of the pattern that matches all remaining characters. As a

 

 

result, a single filter record can pass or block a large set of NetBIOS names. Unlike

 

 

current MAC Filter and Protocol filters for a bridge, a packet may match more than

 

 

one filter record.

 

 

For this reason, NetBIOS Name Caching operates using an ordered list of name

 

 

matching records. A packet is compared against each name matching string in order,

 

 

and the action for the first match is taken. If a packet does not match any NetBIOS

 

 

Name Filter record, the Default NetBIOS Filter Action is taken.

Another Use of

 

Another way of using NetBIOS Name Filters is to pass all NetBIOS broadcasts

Name Filters

except those that are identified in the NetBIOS Name Filter table. This can be used,

 

 

for example, to restrict access to a particular server to the local segment.

Checking NetBIOS

 

The NetBIOS Name Filtering feature does not check every NetBIOS packet. It only

Broadcasts

checks the NetBIOS broadcast packets that are used to initiate a session. Activating

 

 

NetBIOS Name Filtering does not affect NetBIOS sessions already in progress.

 

 

 

Bridging

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Release 5.2M

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EXP Computer S200 Forcing a Local, Domain With, Wildcard Name, Patterns, Another Use, Name Filters, Checking NetBIOS