Compex Systems 802.11N - Manual (Page 69)

Gateway IP: This is the IP address of the host router which resides on the external network and
provides the point of connection to the next hop towards the internet. This can be a DSL modem,
Cable modem, or a WISP gateway router. The device will direct all the packets to the gateway if
the destination host is not within the local network.
Gateway IP address should be from the same address space (on the same network segment) as the
device's external network interface (Wireless interface in the Station case and the LAN interface in
the AP case).
Primary/Secondary DNS IP: The Domain Name System (DNS) is an internet "phone book"
which translates domain names to IP addresses. These fields identify the server IP addresses where
the DNS requests are forwarded by the device.
Primary DNS server IP is mandatory. It is used by the DNS Proxy and for the device management
purpose.
Secondary DNS server IP address is optional. It is used as the fail-over in case the primary DNS
server will become unresponsive.
Enable NAT: Network Address Translation (NAT) enables packets to be sent from the wired
network (LAN) to the wireless interface IP address and then sub-routed to other client devices
residing on it's local network while the device is operating in AP/AP WDS wireless mode and in
the contrariwise direction in "Station/Station WDS" mode.
NAT is implemented using the masquerade type firewall rules. NAT firewall entries are stored in
the iptables nat table, while the device is operating in Router mode. Please refer to the iptables
tutorial for detailed description of the NAT functionality in Router mode.
Static routes should be specified in order the packets should pass-through the based device if the
NAT is disabled in while operating in Router network mode.
Enable DHCP Server: Dynamic Host Configuration Protocol (DHCP) Server assigns IP
addresses to clients which will associate to the wireless interface while the device is operating in
AP/AP WDS wireless mode and assigns IP addresses to clients which will connect to the LAN
interface while the device is operating in Station/Station WDS mode.
Range Start/End: This range determines the IP addresses given out by the DHCP server to client
devices on the internal network which use dynamic IP configuration.
Lease Time: The IP addresses given out by the DHCP server will only be valid for the duration
specified by the lease time. Increasing the time ensure client operation without interrupt, but could
introduce potential conflicts. Lowering the lease time will avoid potential address conflicts, but
might cause more slight interruptions to the client while it will acquire new IP addresses from the
DHCP server.
DHCP Fallback IP: In case the external network interface of the Router is placed in Dynamic IP
Address mode (DHCP) and is unable to obtain an IP address from a valid DHCP server, it will fall
back to the static IP address listed here. In case the IP settings of the device are unknown, they can
be retrieved with the help of the UConfig utility and should be started on the administrator PC
which resides on the same network segment as the device.