Philips SNA6640 User Manual
Page 22
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EN
22
Schedule Rule
You may filter Internet access for local clients based on rules. Each access control
rule may be activated at a scheduled time. Define the time schedule on this page, and
apply the rule on the Access Control page.
Intrusion Detection
Intrusion Detection Feature
Stateful Packet Inspection (SPI) and Anti-DoS firewall protection
(Default: Enabled) - The Intrusion Detection Feature of the ADSL Wireless Modem
Router limits access for incoming traffic at the WAN port. When the SPI feature is
turned on, all incoming packets will be blocked except for those types marked in the
Stateful Packet Inspection section.
RIP Defect (Default: Disabled) - If an RIP request packet is not acknowledged to by
the router, it will stay in the input queue and not be released. Accumulated packets
could cause the input queue to fill, causing severe problems for all protocols. Enabling
this feature prevents the packets from accumulating.
Discard Ping to WAN (Default: Disabled) - Prevent a ping on the ADSL Wireless
Modem Router's WAN port from being routed to the network.
Scroll down to view more information.
Stateful Packet Inspection
This is called a ‘stateful’ packet inspection because it examines the contents of the
packet to determine the state of the communications; i.e., it ensures that the stated
destination computer has previously requested the current communication. This is a
way of ensuring that all communications are initiated by the recipient computer and
are taking place only with sources that are known and trusted from previous
interactions. In addition to being more rigorous in their inspection of packets, stateful
inspection firewalls also close off ports until connection to the specific port is
requested.
When particular types of traffic are checked, only the particular type of traffic
initiated from the internal LAN will be allowed. For example, if the user only checks
‘FTP Service’ in the Stateful Packet Inspection section, all incoming traffic will be
blocked except for FTP connections initiated from the local LAN.
Stateful Packet Inspection allows you to select different application types that are
using dynamic port numbers. If you wish to use the Stateful Packet Inspection (SPI) to
block packets, click on the Yes radio button in the ‘Enable SPI and Anti-DoS firewall
protection’ field and then check the inspection type that you need, such as
Packet Fragmentation, TCP Connection, UDP Session, FTP Service, H.323 Service,
or TFTP Service.
When hackers attempt to enter your network, the SNA6640 can alert you
by e-mail
If the mail server needs to authenticate your identification before sending out any
e-mail, please fill related information in POP3 server, username and password fields.
Otherwise leave the three fields blank.
Connection Policy
Enter the appropriate values for TCP/UDP sessions as described in the following
table.
Note: The firewall does not significantly affect system performance, so we advise enabling
the prevention features to protect your network.
DMZ
If you have a client PC that cannot run an Internet application properly from behind
the firewall, you can open the client up to unrestricted two-way Internet access.
Enter the IP address of a DMZ (Demilitarized Zone) host on this screen. Adding a
client to the DMZ may expose your local network to a variety of security risks, so
only use this option as a last resort.