ZyXEL Communications manual Firewall FAQ, What is a network firewall?, What makes P320W secure?

P320W Support Notes

traffic will be blocked by P320W. To help users get rid of the problem and configuration tasks, P320W will create firewall policy automatically to allow incoming traffic if NAT is enabled in the P320Ws.

Firewall FAQ

What is a network firewall?

A firewall is a system or group of systems that enforces an access-control policy between two networks. It may also be defined as a mechanism used to protect a trusted network from an untrusted network. The firewall can be thought of two mechanisms. One to block the traffic, and the other to permit traffic.

What makes P320W secure?

The P320W is pre-configured to automatically detect and thwart Denial of Service (DoS) attacks such as Ping of Death, SYN Flood, LAND attack, IP Spoofing, etc. It also uses stateful packet inspection to determine if an inbound connection is allowed through the firewall to the private LAN. The P320W supports Network Address Translation (NAT), which translates the private local addresses to one public address. This adds a level of security since the clients on the private LAN are invisible to the Internet.

What are the basic types of firewalls?

Conceptually, there are three types of firewalls:

1.Packet Filtering Firewall

2.Application-level Firewall

3.Stateful Inspection Firewall

Packet Filtering Firewalls generally make their decisions based on the header information in individual packets. These header information include the source, destination addresses and ports of the packets.

Application-level Firewalls generally are hosts running proxy servers, which permit no traffic directly between networks, and which perform logging and auditing of traffic passing through them. A proxy server is an application gateway or circuit-level gateway that runs on top of general operating system such

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