1740 SHDSL 2/4-Wire Router User’s Guide
CHAPTER 6 Packet Filter
Packet filter, a firewall security measure, examines incoming and outgoing packet headers (IP address,
port number, and so on) on the network and determines whether to forward the packets based on user-
defined rules (deny, accept, and count).
The SHDSL router provides packet filter and stateful packet inspection. It has denial of service protection
against attacks such as ICMP Flood, Ping of Death, IP spoofing, Port Scans, Land Attacks, Tear Drop
Attacks, IP Source Route and WinNuke Attacks.
To access the packet filter functions, select Packet Filter from the advanced menu. The screen will
display as below, showing a list of the currently configured filter entries.
6.1.1
Add a Packet Filter entry
To add a Packet Filter, complete the following steps:
STEP 1: Click on the Add button, the Packet Filter Add screen will appear.
STEP 2: Enter values for the parameters (explained below).
STEP 3: Click on the Apply button at the bottom of the page.
Priority
You can enter a number here to assign the priority of a filter, in
case there are overlapping rules. The lower the number the higher
its priority.
Protocol
Select from TCP/UDP/ICMP/IP.
Source IP
Source IP of a packet you wish to filter.
Source Mask
Source Mask of a packet.
Source Port
Source Port of a packet you wish to filter.
1740-A2-GB20-00 July 2004
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