ELSA Cable - Manual (Page 51)

Operating modes and functions
ELSA MicroLink Cable
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and the DHCP server attempts to reassign it this address if it has not already been
assigned to another computer.
The DHCP server also checks whether the address selected is still available in the local
network. As soon as the uniqueness of an address has been established, the requesting
computer is assigned the address found.
Network mask assignment
The network mask is assigned in the same way as the address. If a network mask is
entered in the DHCP module, this mask is used for the assignment. Otherwise, the
network mask from the TCP/IP module is used.
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, however (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 broadcast 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.
DNS server assignment
The addresses of the DNS servers are negotiated and entered during the registration at
the headend.
Default gateway assignment
The router 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.
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.