Tahoe 4681, Руководство пользователя

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Tahoe 4681 (4-port G.shdsl.bis/FastEthernet modem card)
A static ARP entry can be added using arp add:
Tahoe> arp add 10.0.0.3 00:50:13:E9:5C:01
A proxy ARP entry can also be added using arp add :
Tahoe> arp add 10.0.0.4 proxy
When a proxy ARP entry is added, the modem will respond with its own MAC address to the
ARP requests asking of the specified IP address. Thanks to such a behaviour you may select an
IP address from the network connected to the Ethernet interface and assign it to the device on
the other end of WAN link. The modem will pretend to have that IP address, answer to ARP
requests and then forward received packets over the WAN link after an appropriate routing entry
is added.
The dynamic hardware address resolution may be disabled using the ifconfig command. When
disabled, only those stations whose IP and MAC addresses are entered staticaly into the ARP
table using the arp add command are allowed to connect to the modem.
bridge
The bridge command enables or disables the bridge mode, in which two interconnected LANs
create united one in the hardware layer. The stations in both LANs behave like if they were con-
nected to one Ethernet switch, e.g. PCs working under Microsoft® Windows™ operating system
will see each other in the network neighbourhood.
Following settings are available:
off
– regular TCP/IP (Layer 3) routing
on
– the bridge mode is enabled, but the modem is still available under its IP address and
thus may be managed remotely
transparent
– completely transparent bridge, modem does not respond to its IP address
dumb
– the bridge mode is enabled, but no MAC address checking is performed. In the
regular bridge mode the modem checks on which interface (G.shdsl or LAN) the packet’s
destination MAC address was heard and decides whether to forward that packet or not. The
dumb mode does not do any MAC checking, thus is more efficient. It will work properly in
most cases, because the external Ethernet switch does the MAC checking on its own.
dumbtrans
– a combination of two above modes, no MAC address check is performed and
the modem isn’t available under its IP address