3Com PathBuilder S200 Series Owner's Manual page 81

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
T0008-16F
Bridge Filtering
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Release 5.2M