Netgear FVS338 참조 가이드

Firewall Protection and Content Filtering

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The ProSafe VPN Firewall 50 provides you with Web content filtering options such as Block Sites 
and Keyword Blocking. Parents and network administrators can establish restricted access policies 
based on time-of-day, Web addresses and Web address keywords. You can also block Internet 
access by applications and services, such as chat or games. It also provides various firewall 
activity reports and instant alerts via e-mail.

A firewall is a special category of router that protects one network (the “trusted” network, such as 
your LAN) from another (the untrusted network, such as the Internet), while allowing 
communication between the two. 

A firewall incorporates the functions of a NAT (Network Address Translation) router, while 
adding features for dealing with a hacker intrusion or attack, and for controlling the types of traffic 
that can flow between the two networks. Unlike simple Internet sharing NAT routers, a firewall 
uses a process called stateful packet inspection to protect your network from attacks and 
intrusions. NAT performs a very limited stateful inspection in that it considers whether the 
incoming packet is in response to an outgoing request, but true Stateful Packet Inspection goes far 
beyond NAT.

Firewall rules are used to block or allow specific traffic passing through from one side to the other. 
You can configure up to 600 rules on the FVS338. Inbound rules (WAN to LAN) restrict access by 
outsiders to private resources, selectively allowing only specific outside users to access specific 
resources. Outbound rules (LAN to WAN) determine what outside resources local users can have 
access to.

A firewall has two default rules, one for inbound traffic and one for outbound. The default rules of 
the FVS338 are:

•

Inbound: Block all access from outside except responses to requests from the LAN side.