ELSA LANCOM Business LC-4X00, Руководство пользователя

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Operating modes and functions
ELSA LANCOM Business
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In a Microsoft Network, the computers are only addressed via their names. Multiple
computers can be organized into groups, and multiple groups can be grouped further as
scopes. The names used must be known throughout the network for all computers to be
able to access the resources of the others. NetBIOS computers issue their names into
the network at regular intervals to eliminate the necessity of maintaining tables of known
names on each computer.
The names publicized in this manner should, of course, be collected and made available
at a central location in the Microsoft Network. If two Microsoft Networks are to be
connected using a router, then such a name collection point, a so-called NetBIOS
nameserver (NBNS), must be present on both sides.
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A WINS server (Windows Internet Name Service Server) can be installed in the
network for this purpose.
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However, a second option is also available, since many Microsoft Networks can or
must make do without a server of their own: Information about the names in use can
be placed on a ”billboard“ of sorts, on which all participating computers only post
their names and IP addresses. In this case, the individual computers are responsible
for the consistency of their names within the network.
The
ELSA LANCOM Business offers such a billboard. The interconnection of Microsoft
Networks is thus possible without a server as a result of this simple realization of the
NBNS. The computers in the networks to be interconnected thus publicize their names
and add them to the billboards in the respective remote networks.
Handling of NetBIOS packets
The highly verbose nature of Windows computers can result in high charges for ISDN
connections, as each NetBIOS packet containing name information automatically
launches a call establishment (e.g. to a previously set up ISP). The connection remains
permanently established due to these packets, resulting in high connect charges without
the transfer of actual user data.
An ELSA LANCOM Business can either route or spoof the NetBIOS packets to prevent the
establishment of unnecessary connections:
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In the NetBIOS module, it is possible to specify the remote stations to which the
name information should be transferred via NetBIOS to ensure the routing of those
packets that are actually required. After the NetBIOS module has been switched on
and an unspecified waiting time has elapsed, a connection is established to the
NetBIOS remote stations (insofar as these are not individual remote access
workstations). The duration of the waiting period will be increased if the connection
cannot be established. The following exchange of NetBIOS information then fills
the billboard for the first time.
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In its proxy function, the unit answers queries to computers already known in the
NetBIOS module (on the billboard) by proxy for those computers. After the initial