ELSA Lancom DSL/10 Office, Руководство пользователя

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Operating modes and functions
ELSA LANCOM DSL/10 Office
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– The device then enables its own DHCP server if no other DHCP servers are found.
Whether the DHCP server is active or not can be seen in the DHCP statistics.
The default state is 'auto'.
How are the addresses assigned?
IP address assignment
Before the DHCP server can assign IP addresses to the computers in the network, it first
needs to know which addresses are available for assignment. Three options exist for
determining the available selection of addresses:
K
The IP address can be taken from the address pool selected (start address pool to
end address pool). Any valid addresses in the local network can be entered here.
K
It then uses the IP address '10.0.0.254' for itself and the address pool '10.x.x.x' for
the assignment of IP addresses in the network. In this state, the DHCP server only
assigns IP addresses and their validity to the computers in the network, but not the
other information.
If only one computer in the network is started up that is requesting an IP address via
DHCP with its network settings, a device with an activated DHCP module will offer this
computer an address assignment. A valid address is taken from the pool as an
IP address. If the computer was already assigned an IP address at some point in the past,
it requests this same address 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.