Specifications

IP Address Assignment: Static or Dynamic?
AVM Access Server – 6 AVM Access Server for Experts 105
IP Address Assignment: Static or Dynamic?
The AVM Access Server defines two kinds of address ranges: those for
static and those for dynamic address assignments. With dynamic IP
address ranges, the user is only assigned an IP address when the con-
nection is activated, and the address may be a different one each time
the connection is dialed up. With a static address range, the user is as-
signed an IP address before the connection is dialed up, and the user
always has the same address. The IP address range is defined for a
group of remote users. When an IP address range for static assign-
ments has been defined, a free IP address from that address range is
suggested for assignment to the new user each time a user is created.
IP addresses can be assigned both from the local IP subnetwork and
from a new subnetwork.
IP Addresses from the Local Subnetwork
Example:
In this case the Access Server performs “proxy ARP”. This means that
all ARP (Address Resolution Protocol) requests concerning IP address-
es in the remote users’ range (e.g. “Who has 192.168.10.200?”) are an-
swered by the Access Server with its own MAC address. This ensures
that packets from LAN hosts for remote users are sent to the Access
Server, which forwards them to the remote users.
If the remote user group is assigned an IP address range in the LAN
subnet, make sure that no addresses from this range are used by com-
puters in the LAN! Otherwise, an ARP request for the address with a du-
plicate assignment would be answered by two computers, the Access
Server and the other computer in the LAN. There is no way to predict
which answer would reach the requesting computer first.
AVM Access Server: 192.168.10.1
Local network: 192.168.10.0 / 24 (192.168.10.1 to 192.168.10.254)
IP address range for
assignment to remote
users:
192.168.10.192 / 26 (192.168.10.193 to
192.168.10.254)