ELSA LANCOM Business LC-4X00, Руководство пользователя

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Operating modes and functions
ELSA LANCOM Business
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– In the event that IP addresses were already in use in your network before
converting to DHCP operation, select the option 'I would like to adjust the
settings manually' in the wizard. In the next window, enter an unused IP address
from the previously-used address range and activate the DHCP server.
The wizard now assigns the selected IP address and associated netmask to the
router. On the basis of this IP address, the device then determines the valid
address pool for the DHCP assignment.
– After a few seconds, all of the computers in the network will be checked and are
assigned a new IP address by the DHCP server as required. The computers also
receive additional parameters such as the broadcast address, DNS server,
default gateway, etc.
Manual configuration
If configuration using the
ELSA LANconfig wizard is not for you, set the parameters for
the DHCP server manually: in
ELSA LANconfig in the 'TCP/IP' configuration section on the
'DHCP' tab or in the /
Setup/DHCP-module
menu).
DNS server
The domain name service (DNS) in TCP/IP networks provides the association between
computer names or network names (domains) and IP addresses. This service is required
for Internet communications, to return the correct IP address for a request such as
'www.elsa.com' for example. However, it's also useful to be able to clearly associate IP
addresses to computer names within a local network or in a LAN interconnection.
What does a DNS server do?
The names used in DNS server requests are made up of several parts: one part consisting
of the actual name of the host or service to be addressed; another section specifies the
domain. Specifying the domain is optional within a local network. These names could
thus be 'www.domain.com' or 'ftp.domain.com', for example.
If there is no DNS server in the local network, all locally unknown names will be searched
for using the DEFAULT route. By using a DNS server, it's possible to immediately go to
the correct remote station for all of the names with known IP addresses. In principle, the
DNS server can be a separate computer in the network. However, the following reasons
speak for locating the DNS server directly in the
ELSA LANCOM Business:
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An ELSA LANCOM Business can automatically distribute IP addresses for the
computers in the local network when in DHCP server mode. In other words, the
DHCP server already knows the names and IP addresses of all of the computers in
its own network that were assigned IP addresses via DHCP. With the dynamic
address assignments of a DHCP server, an external DNS server might have