A device designed to prohibit unauthorized access to a network or machine via the network connection.  This device acts as a gateway between the unprotected network and the protected machine or network.

There is also a concept of a Personal FireWall, which is program that monitors the network usage on a machine.  While this cannot provide the same level of security as a separate FireWall appliance, it may be sufficient for the typical home user.

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'''Firewall related technology and terms and products'''

* ''Firewall basics'' at http://www.securitydocs.com/library/2413
* ''Choosing the best FireWall'' at http://www.sans.org/rr/papers/index.php?id=951

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[moved from SpyWare]

Agnitium has a free one http://www.agnitum.com/download/ and the latest MS products have personal firewalling built in. A free antivirus program that does not expire and allows updates is AVG: http://www.grisoft.com/us/us_dwnl_free.php

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CategorySecurity