Firewalls are devices—software and hardware—that prevent unauthorised
entry into a system. Any network interface has 65,535 possible
points of connection (these are called ports). When a PC is
connected to the network, these ports are accessible by any other
PC on the network. This presents an opportunity for those with
“malafide” intentions to access the contents of a PC without permission.
A firewall usually operates by blocking or monitoring all
ports of the interface. Traffic can be inbound or outbound. When
data is sent to a user’s PC, it is inbound traffic, and when the
user’s PC is sending data, it is outbound traffic. Usually, inbound
traffic is considered more dangerous since it could be a virus or
Trojan trying to gain access into the system. But outbound traffic
can also be harmful, since it could be an application that is surreptitiously
passing data to someone else—for example, a keylogger
could be operational.
0 comments:
Post a Comment