Internet security is the prevention of unauthorized access and/or damage to computer systems via internet access. Most security measures involve data encryption and passwords. Data encryption is the translation of data into a form that is unintelligible without a deciphering mechanism. A password is a secret word or phrase that gives a user access to a particular program or system.
FIREWALL--A firewall blocks any unauthorized ports on your computer, thus restricting unfettered access. A stateful firewall is a more secure form of firewall, and system administrators often combine a proxy firewall with a packet-filtering firewall to create a highly secure system. Most home users use a software firewall. These types of firewalls can create a log file where it records all the connection details (including connection attempts) with the PC.
Product types include : Cisco Advanced Security Appliances , Netscreen by Juniper , and others
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