### act | actuation | drive:

Firewall
* Add firewall-style support to an operating system.
* FireWall tracks the number of nodes on all internal interfaces beginning from initial installation.
* Most firewalls are dual-homed, meaning that they have two physical network devices
  - distinguish between inbound and outbound traffic
* Some firewalls act as bridges rather than routers
  - also offer multiple encryption schemes and enhanced authentication
  - automatically detect the type of cable, and some have a switch that needs to be set
  - use packet filters which block packets used by traceroute
* act much like the manager of a safe deposit box vault.
* add an extra layer of security
  - security to financial, student and corporate records
* allow access to the outer world while shielding the protected areas from attack
  - authorized users access to a network or computer system
  - users direct access to applications and data through a security door
* also hamper online gaming.
* also provide a central point for logging and auditing Internet traffic
  - companies with other types of protection from network intrusion
* are a common and tested Internet security feature
  - cornerstone in current network security
  - key ingredient to any network that is hooked to the Internet
  - means of keeping intruders out of a local network
  - necessary form of online security
  - relatively new solution to security problems against intruders
  - security mechanism that protect the site from intended or unintended damage
* are an integral part of a total security system
  - any security architecture
  - another method of controlling access
  - books
  - clever mechanisms typically a combination of hardware and software
  - devices that allow network administrators to limit traffic that it deems harmful
  - electronic security screens
* are generally a combination of vertical walls between sections of a building
  - hard on the outside and non existent on the inside
  - important security tools
  - like security guards that protect high-risk buildings
* are network barriers designed to keep out crackers
  - blocks that restrict access to or from part of the network
  - no longer a barrier to communicating over the Internet
  - now prevalent throughout the public and private sectors
* are one of the fastest growing technical tools in the field of information security
  - present to protect against unauthorized access from the Internet
* are security devices used to protect companies from unauthorized access to their servers
  - perimeters for active information infrastructure components
  - systems
  - software programs to ward off hackers
  - systems, which control access policy between two or more networks
* are the network s response to the host security problem
  - same technologies that major corporations use to protect their networks
  - traffic cops of network security
  - very important tools in protecting an environment connected to a network
* block direct or unauthorized access via the Internet and the intranet.
* can also be software applications
  - be specialized hardware devices or a combination of hardware and software
  - cause problems for online learners who access classes from work
  - have an impact on performance
* can help eliminate unauthorized access to a company's network
  - restrict traffic to the server
  - keep intruders out of corporate networks, if properly used
  - potentially block huge amounts of traffic
  - provide a secure connection between two networks
* combine hardware and software to block unwanted communications into and out of a network.
* come in all shapes and sizes
  - both hardware and software forms
  - hardware and software varieties
  - several styles and purport to protect the internal network in different ways
  - the form of software, hardware, or a combination of both
* consist of one or more routers that accept, reject or edit transmitted information.
* control the flow of traffic between networks.
* create barriers in order to prevent unauthorized access to a network.
* ensure the security of data.
* exist so that no client can obtain access to areas personal to another client.
* filter both incoming and outgoing network traffic
  - what comes in and leaves a private server
* focus on entry policy, admissions, and denial of service.
* have a limited ability to examine incoming traffic
  - nothing to do with viruses
* help prevent and log network access
  - thwart external threats
* is the biggest buzzword in security.
* keep unauthorized users out.
* often allow a wide variety of traffic to go outbound.
* perform security checks by inspecting each passing packet.
* permit desired services coming from the outside, such as Internet email, to pass through.
* prevent network penetration
  - savings in one category from being applied toward increased spending in another
* primarily use one of three technologies to filter data.
* protect against administrator errors
  - many attacks on the network and system infrastructure
  - consumers from hackers and other unwanted activities directed at their PCs
  - information in internal computer networks from external access
  - internal systems from Internet attacks
  - networks from computer hackers
  - one part of a network from another
  - sensitive internal records from Internet client software snooping
  - services from unauthorized access
  - system and database information
  - the network integrity and only allow legitimate traffic
* provide a centralized location for external security services
  - perimeter defense against intrusion from the outside network
  - access control and auditing for inter-network traffic
  - additional security, either permitting or preventing access outside the firewall
* provides security to the network using userids, passwords, encryption techniques, etc.
* react to security threats when they arise.
* refers to a server's protection against unauthorized access from the Internet.
* relatively generic term for methods of filtering access to a network.
* rely on knowing where traffic is going.
* restrict access at the network layer.
* security barrier set up between a company's internal and outside systems.
* serve as a protective gateway between an organization's internal network and the Internet
  - to define the services and access that are permitted to each user
* type of network perimeter defense.
* use hardware and software to protect the business' internal network resources
  - one or more mechanisms to enforce policy and provide protection
* usually involve a total block on all outside connections into the network.
* work because only a few machines running a few services are exposed to attack
  - by restricting the number and types of communications from one network to another
* work, and have a place in the Internet.
+ Firewall (networking), Other things firewalls are used for, Tunnelling: Software :: Internet security
  * Firewalls can provide a secure connection between two networks. This is called 'tunnelling'. The data may be encrypted. It is unencrypted at the other end. Since the firewalls are doing this, the rest of the network is unaware of it.