Lancom Systems LCOS 3.50 - Manual (Page 95)

̈ Chapter 7: Routing and WAN connections LANCOM Reference Manual LCOS 3.50
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Routing and
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telecomputer), the LANCOM assigns it an IP address for the duration of the
connection, enabling communications to take place.
This type of address assignment is carried out during PPP negotiation and
implemented only for connections via WAN. In contrast, the assignment of
addresses via DHCP is (normally) used within a local network.
Assignment of an IP address will only be possible if the LANCOM can
identify the remote station by its call number or name when the call
arrives, i.e. the authentication process has been successful.
Examples
̈ Remote access
Address assignment is made possible by a special entry in the IP routing
table. 255.255.255.255 is specified as the network mask as the IP address
to be assigned to the remote site in the 'Router-name' field. In this case,
the router name is the name, with which the remote site must identify
itself to the LANCOM.
In addition to the IP address, the addresses of the DNS and NBNS servers
(Domain Name Server and NetBIOS Name Server) including the backup
server from the entries in the TCP/IP module are transmitted to the remote
station during this configuration.
So that everything functions properly, the remote site must also be
adjusted in such a way that it can obtain the IP address and the name
server from the LANCOM. This can be accomplished with Windows dial-
up networking through the settings in the 'TCP settings' under 'IP
address' and 'DNS configuration'. This is where the options 'IP address
assigned by server' and 'Specify name server addresses' are activated.
̈ Internet access
If Internet access for a local network is realized via the LANCOM, the
assignment of IP addresses can occur in a reverse manner. Configurations
are possible in which the LANCOM does not have a valid IP address in the
Internet and is assigned one by the Internet provider for the duration of
the connection. In addition to the IP address, the LANCOM also receives
information via the DNS server of the provider during the PPP negotiation.
In the local network, the LANCOM is only known by its internal valid
intranet address. All workstations in the local network can then access the
same Internet account and also reach e.g. the DNS server.