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
welcome savings, IP masquerading has the added benefit of guarding very
effectively against attacks on the local network from the Internet.
Two addresses for the router
Masquerading pits two opposing requirements of the router against one
another: While it must have an IP address which is valid on the local network,
it must also have an address valid on the Internet. Since these two addresses
may not in principle be located on the same logical network, there is only one
solution: two IP addresses are required.
The router is therefore assigned an Inter net address and an intra net
address, each with its own fitting network mask. Use the 'Masquerade'
option in the routing table to inform the router which of the two addresses to
use when transferring the packets.
'Off': No masquerading.
'Dynamic': This entry requests a random IP address valid in the Internet
from your provider which is then used for the connection and
masquerading.
'Static': This entry requests a specific IP address entered under /setup/
TCP from your provider which is then used for the connection and
masquerading.
If a specific address is requested from the provider, two options are available
for the actual address assignment:
The provider assigns the desired address to the router. The network mask
now decides how many computers are masked behind the router.
IP address with full '255.255.255.255' network mask: This is your own
unique IP address, registered by the NIC. None of the other
computers on the network have valid Internet addresses and are
masked behind the router's fixed address.
IP address with an incomplete network mask, e.g. '255.255.255.248':
You have several registered IP addresses, one of which you assign to
the router. The remaining IP addresses are assigned permanently to
devices on the Intranet, which can then use unmasked connections to
access the Internet. The other devices can still access the Internet
using masked connections.
The provider assigns another address to the router. Then all computers
in the local network are masked behind the assigned address.