Firewall (computing) A firewall (firewall in English ) is part of a system or network that is designed to block unauthorized access while allowing authorized communications . This is a device or group of devices configured to permit, restrict, encrypt, decrypt the traffic between different areas on the basis of a set of standards and other criteria.
Firewalls can be implemented in hardware or software, or a combination of both. Firewalls are frequently used to prevent unauthorized Internet users from accessing private networks connected to the Internet, especially intranets. All messages entering or leaving the intranet pass through the firewall, which examines each message and blocks those that do not meet specified security criteria. It is also common to connect the firewall to a third network, called Demilitarized Zone or DMZ , which houses the servers in your organization that should be accessible from the outside network. A properly configured firewall adds a necessary protection to the network, but in no case should be considered sufficient. The computer security covers more areas and more jobs and levels of protection.
types of firewalls: Level
application gateway applies security mechanisms to specific applications such as FTP and Telnet servers. This is very effective, but can impose performance degradation.
Circuit-level gateway
Applies security mechanisms when a TCP connection or UDP is set. Once the connection has been made, packets can flow between the hosts without further control. Allows the establishment of a session that originates from an area of \u200b\u200bgreater security to a lower security area.
network layer firewall or packet filter
works at the network level (level 3) of the protocol stack (TCP / IP) and IP packet filter. At this level you can make filters for different IP packet fields: source IP address, destination IP address, etc. Often in this type of firewall to filter fields as transport layer (level 4) as the source and destination port, or data link layer (level 2) as the MAC address. This is one of the main types of firewalls. It is considered fairly effective and transparent but difficult to configure.
Application Layer Firewalls Work
the application level (level 7), so that the filter can be adapted to characteristics of the protocols at this level. For example, if traffic is HTTP can be performed according to filtered URL to which you are trying to access.
A firewall traffic at 7 HTTP is often referred proxy, and allows the computers of an organization come to the Internet in a controlled manner. A proxy effectively hides the true network addresses.
Personal Firewall is a special case of firewalls that are installed as software on a computer, filtering communications between that computer and the rest of the network. It is used for both a personal level.
advantages of portefuegos:
Intrusion Protect .- Access to certain segments of the network of an organization is only allowed from machines approved in other segments of the organization or the Internet.
protection of private information .- You can set different levels of access to information, so that an organization each defined user group has access only to services and information that are strictly necessary.
access Optimization .- Identifies internal network elements and optimizes the communication between them is more direct. This helps to reconfigure security parameters.
LIMITATIONS OF FIRE:
limitations arise from the very definition of firewall, traffic filtering. Any type of computer attack that uses traffic accepted by the firewall (for open TCP ports used specifically, for example) or simply not use the network, will remain a threat. The following list shows some of these risks
A firewall can not protect against those attacks that traffic does not pass through it.
The firewall can not protect against threats that are submitted by users or internal attacks negligent. The firewall can not prevent corporate spies copying sensitive data in physical storage media (disks, memories, etc..) And withdraw from the building.
The firewall can not protect against attacks social engineering.
The firewall can not protect against possible attacks to the internal network from viruses through files and software. The real solution is that the organization should be aware of installing antivirus software on each machine to protect against viruses that arrive via any storage medium or other source.
The firewall does not protect of the security flaws of the services and protocols which traffic is allowed. Must be configured properly and ensure the safety of the services that are published on the internet.
0 comments:
Post a Comment