User guide

A DVANCED S ETUP
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Firewall
The Wireless 54Mbps ADSL Router’s firewall inspects packets at the
application layer, maintains TCP and UDP session information,
including time-outs and the number of active sessions, and provides
the ability to detect and prevent certain types of network attacks.
Network attacks that deny access to a network device are called
Denial-of-Service (DoS) attacks. DoS attacks are aimed at devices
Parameter Description
Flags Indicates the route status:
C = Direct connection on the same subnet.
S = Static route.
R = RIP (Routing Information Protocol) assigned route.
I = ICMP (Internet Control Message Protocol) Redirect route.
Network
Address
Destination IP address.
Netmask The subnetwork associated with the destination.
This is a template that identifies the address bits in the destination
address used for routing to specific subnets. Each bit that corresponds
to a “1” is part of the subnet mask number; each bit that corresponds to
“0” is part of the host number.
Gateway The IP address of the router at the next hop to which frames are
forwarded.
Interface The local interface through which the next hop of this route is reached.
Metric When a router receives a routing update that contains a new or changed
destination network entry, the router adds 1 to the metric value indicated
in the update and enters the network in the routing table.