Lancom Systems LCOS 3.50 - Manual (Page 275)

̈ Chapter 13: Server services for the LAN LANCOM Reference Manual LCOS 3.50
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Server servic
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Otherwise, the network mask from the TCP/IP module is used. The order is the
same as during the assignment of the addresses.
Broadcast address assignment
Normally, an address yielded from the valid IP addresses and the network
mask is used for broadcast packets in the local network. In special cases, how-
ever (e.g. when using subnetworks for some of the workstation computers), it
may be necessary to use a different broadcast address. In this case, the broad-
cast address to be used is entered in the DHCP module.
The default setting for the broadcast address should be changed by
experienced network specialists only. Incorrect configuration of this
section can result in the undesired establishment of connections sub-
ject to connect charges!
Standard gateway assignment
The device always assigns the requesting computer its own IP address as a
gateway address.
If necessary, this assignment can be overwritten with the settings on the
workstation computer.
DNS and NBNS assignment
This assignment is based on the associated entries in the 'TCP/IP-module'.
If no server is specified in the relevant fields, the router passes its own IP
address as a DNS address. This address is determined as described under 'IP
address assignment'. The router then uses DNS-forwarding (also see 'DNS-
forwarding'), to resolve DNS or NBNS requests from the host.
Period of validity for an assignment
The addresses assigned to the computer are valid only for a limited period of
time. Once this period of validity has expired, the computer can no longer use
these addresses. In order for the computer to keep from constantly losing its
addresses (above all its IP address), it applies for an extension ahead of time
that it is generally sure to be granted. The computer loses its address only if it
is switched off when the period of validity expires.
For each request, a host can ask for a specific period of validity. However, a
DHCP server can also assign the host a period of validity that differs from what