3. Configuring the DSL Router
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Security
The router offers security via the following:
Filtering. A filter consists of a set of rules applied to a specific in terface to
indicate whether a packet received or sent on that interface is forward ed or
discarded. Filters are applied to traffic in either the inbound (from the Ethernet
port) or outbound (from the DSL port) direction on that interface:
— IP Protocol Type: TCP, UDP, or ICMP
— ICMP Message Type, Code
— TCP/UDP Ports
— Source/Destination IP Address
— Ethernet Type
Always enabled:
— Land Bug Prevention
— Smurf Attack Prevention
NOTE:
All Hotwire DSL Router filters are configured on the Hotwire DSL card. Some
routing parameters that affect filtering, such as enabling bridging or routing,
can only be configured on the DSL router.

IP Protocol Type Filtering

By default, IP Protocol Type (IP) filtering is disabled on the Hotwire DSL card for
the DSL router. If enabled, filtering provides security advantages on LANs by
restricting traffic on the network and hosts based on the source and /or destination
IP addresses.
There is one filter per direction, with a maximum of 33 rules per filter. For IP filters,
all filter access rules with a source host IP address are applied fir st, with all rules
with a destination host IP address applied next. The remaining filters are applied in
the order in which they were configured.
For additional information about IP filtering, refer to the Hotwire MVL, ReachDSL,
RADSL, IDSL, and SDSL Cards, Models 8310, 8312/8314, 8510/8373/8374,
8303/8304, and 8343/8344, User’s Guide.