ELSA LANCOM Business 6000, Руководство пользователя

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Technical basics
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ELSA LANCOM Business 6000
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EN
The router now responds to the request for the MAC address to the IP address
192.168.110.123 with its own MAC address. This ensures that all packets in
the LAN for the teleworker are now automatically sent to the router, and that
data is sent on to the computer at the other end of the ISDN connection.
7.5.4 Local routing
You know the following behavior of a workstation within a local network: The
computer searches for a router to assist with transmitting a data packet to an
IP address which is not on its own LAN. This router is usually notified to the
operating system by its property of being the default router or gateway. It is
often only possible to enter one default router which is supposed to be able
to reach all the IP addresses which are unknown to the workstation computer
if there are several routers in a network. Occasionally, however, this default
router cannot reach the destination network itself but does know another
router which can find this destination.
How can you assist the workstation computer now?
By default, the router sends the computer a response with the address of the
router which knows the route to the destination network (this response is
known as an ICMP redirect). The workstation computer then accepts this
address and sends the data packet straight to the other router.
Certain computers, however, do not know how to handle ICMP redirects. To
ensure that the data packets reach their destination anyway, use local
routing (in
ELSA LANconfig in the 'IPX/SPX' configuration section on the
'Routing' tab or in the /
Setup/IP-router-module/Loc.
routing On
menu). In this way you instruct the router itself in your device
to send the data packet to other routers. In addition, in this case no more
ICMP redirects will be sent.
This may seem to be a good idea in principle, but local routing should still only
be used as a last resort, since this function leads to doubling of the number
of data packets being sent to the destination network required. The data is
first sent to the default router and is then sent on from here to the router
which is actually responsible in the local network.
7.5.5 Dynamic routing with IP RIP
In addition to the static routing table ELSA routers also have a dynamic
routing table containing up to 128 entries. Unlike the static table, you do not
fill this out yourself, but leave it to be dealt with by the router itself. It uses