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Cisco RV320/RV325  Administration Guide 75
 
Firewall
The primary objective of a firewall is to control the incoming and outgoing network 
traffic by analyzing the data packets and determining whether it should be 
allowed through or not, based on a predetermined rule set. A network firewall 
builds a bridge between an internal network that is assumed to be secure and 
trusted and another network, usually an external (inter)network such as the 
Internet that is assumed not to be secure and untrusted.
General
General firewall controls manage the features typically used by Internet browsers 
and applications.
Enabling Firewall Features
To enable the Firewall, check Enable. The following firewall features can be 
enabled or disabled as needed:
• SPI (Stateful Packet Inspection)—Monitors the state of network 
connections (such as TCP streams, UDP communication) traveling across it. 
The firewall distinguishes legitimate packets for different types of 
connections. Only packets matching a known active connection are allowed 
by the firewall; others are rejected.
• DoS (Denial-of-service )—Detects attempts to cause a server overload. In 
general terms, DoS attacks are implemented by either forcing the targeted 
computer(s) to reset, or consuming its resources so that it can no longer 
provide its intended service or obstructing the communication media 
between the intended users and the victim so that they can no longer 
communicate adequately.
• Block WAN Request—Drops TCP requests and ICMP packets.
• Remote Management—Allows remote management of the device when 
enabled. The port is 443 by default. It can be changed to any user-defined 
port. The string will be https://<wan-ip>:<remote-management-port>