What is an IP address?

An IP address is a number that uniquely identifies each computer on the Internet. It can be permanently assigned or supplied by an Internet service provider each time a computer connects. IP address blocking , also called IP banning, configures a network to refuse requests from specific IP addresses. IP addresses are blocked for various reasons, including enforcing standards for online behavior, protecting networks against attacks, and censoring access to information.

What does IP address blocking mean?

IP address blocking is the practice of configuring a network to reject requests from specific IP addresses . An IP address is a unique numeric identifier for every device on the Internet. IP addresses are blocked for various reasons, such as enforcing online behavior standards, protecting networks from attacks, and censoring access to information. Networks can log IP addresses to determine if there have been previous interactions and deny access to addresses that are undesirable or show concerning patterns. Firewalls use IP address blocking as part of their security system.

Why would someone want to block an IP address?

An IP address is a unique number that identifies each computer on the internet. IP addresses are blocked for multiple reasons, such as enforcing standards for online behavior, like a school restricting students from accessing certain websites. They can also protect networks against attacks and censor access to information. Networks can deny access to IP addresses that have been marked as undesirable or show concerning patterns, such as continuously failing to input the correct login information, which could be a sign of a brute force hacking attempt.

How does IP address blocking work on a website?

IP address blocking, also known as IP banning, involves configuring a network to reject requests from specific IP addresses. An IP address is a unique number that identifies each computer on the Internet. Websites block IP addresses for various reasons, such as enforcing online behavior standards, protecting against attacks, and censoring information. Networks can log IP addresses of devices requesting data, and firewalls deny access to addresses marked as undesirable or showing concerning patterns, like failed login attempts.

What are some problems caused by IP address blocking?

IP address blocking, also known as IP banning, involves configuring a network to reject requests from specific IP addresses. While it serves purposes like enforcing online behavior standards, protecting networks from attacks, and censoring information, it also presents certain problems. One challenge lies in the fact that IP addresses are not always static; they can be dynamically assigned and reused, such as with guests at hotels. This complicates precise blocking efforts. Additionally, users can circumvent IP bans through proxy servers, virtual private networks, and tools like Tor, which disguise their IP addresses. Even restarting a router can sometimes result in a new IP address, rendering the ban ineffective.

How do people and organizations get around IP address blocking?

IP address blocking is used to enforce online behavior standards, protect networks, and censor information. However, several methods can be used to circumvent this security measure. Circumvention methods: * Proxy servers, VPNs, and Tor These disguise IP addresses. * DHCP lease renewal Users can obtain a new IP address from their internet service providers, sometimes by restarting their router or modem. * Anti-detect browsers These are designed to evade detection. To counter circumvention: * Prefix blocking Block multiple unwanted IP addresses sharing a prefix, though this risks denying service to innocent users. * VPN blocking Block IP addresses accessed by multiple users, as many VPN services share a limited number of IP addresses among subscribers. * Proxy servers Use defensively. * Legal measures Some governments have made IP ban circumvention a criminal offense.

IP address blocking

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Also called:: IP banning

Related Topics:: computer network; firewall; IP address; TCP/IP

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IP address blocking

computing

Also known as: IP banning

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Adam Volle

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Top Questions

What is an IP address?
An IP address is a number that uniquely identifies each computer on the Internet. It can be permanently assigned or supplied by an Internet service provider each time a computer connects.

IP address blocking, also called IP banning, configures a network to refuse requests from specific IP addresses. IP addresses are blocked for various reasons, including enforcing standards for online behavior, protecting networks against attacks, and censoring access to information.
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What does IP address blocking mean?
IP address blocking is the practice of configuring a network to reject requests from specific IP addresses. An IP address is a unique numeric identifier for every device on the Internet.

IP addresses are blocked for various reasons, such as enforcing online behavior standards, protecting networks from attacks, and censoring access to information. Networks can log IP addresses to determine if there have been previous interactions and deny access to addresses that are undesirable or show concerning patterns. Firewalls use IP address blocking as part of their security system.
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1. Definition of IP address
2. IP address blocking
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Why would someone want to block an IP address?
An IP address is a unique number that identifies each computer on the internet.

IP addresses are blocked for multiple reasons, such as enforcing standards for online behavior, like a school restricting students from accessing certain websites. They can also protect networks against attacks and censor access to information. Networks can deny access to IP addresses that have been marked as undesirable or show concerning patterns, such as continuously failing to input the correct login information, which could be a sign of a brute force hacking attempt.
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How does IP address blocking work on a website?
IP address blocking, also known as IP banning, involves configuring a network to reject requests from specific IP addresses. An IP address is a unique number that identifies each computer on the Internet.

Websites block IP addresses for various reasons, such as enforcing online behavior standards, protecting against attacks, and censoring information. Networks can log IP addresses of devices requesting data, and firewalls deny access to addresses marked as undesirable or showing concerning patterns, like failed login attempts.
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1. IP address
2. IP address blocking
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What are some problems caused by IP address blocking?
IP address blocking, also known as IP banning, involves configuring a network to reject requests from specific IP addresses. While it serves purposes like enforcing online behavior standards, protecting networks from attacks, and censoring information, it also presents certain problems.

One challenge lies in the fact that IP addresses are not always static; they can be dynamically assigned and reused, such as with guests at hotels. This complicates precise blocking efforts. Additionally, users can circumvent IP bans through proxy servers, virtual private networks, and tools like Tor, which disguise their IP addresses. Even restarting a router can sometimes result in a new IP address, rendering the ban ineffective.
2 Britannica Sources
1. IP address
2. IP address blocking
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
How do people and organizations get around IP address blocking?
IP address blocking is used to enforce online behavior standards, protect networks, and censor information. However, several methods can be used to circumvent this security measure.

Circumvention methods:
* Proxy servers, VPNs, and Tor These disguise IP addresses.
* DHCP lease renewal Users can obtain a new IP address from their internet service providers, sometimes by restarting their router or modem.
* Anti-detect browsers These are designed to evade detection.

To counter circumvention:
* Prefix blocking Block multiple unwanted IP addresses sharing a prefix, though this risks denying service to innocent users.
* VPN blocking Block IP addresses accessed by multiple users, as many VPN services share a limited number of IP addresses among subscribers.
* Proxy servers Use defensively.
* Legal measures Some governments have made IP ban circumvention a criminal offense.
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1. IP address blocking
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IP address blocking, configuring a network to refuse requests sent from specific IP addresses. IP addresses are blocked for multiple reasons, including to enforce standards for online behavior (e.g., a school restricting its students from accessing certain websites), protect networks against attacks, and censor access to information.

All devices connected to the Internet have unique IP addresses. Networks can log the IP addresses of any device from which their data is requested, enabling them to determine if the two have previously interacted, and, if so, when. This ability is used as part of a network’s “firewall” (security system) to deny access to addresses that have either been marked as undesirable or which show concerning patterns. For example, a firewall might notice that the user of an IP address is continuously failing to input the correct login information for its network—a telltale sign of a brute force hacking attempt—and temporarily deny that address additional opportunities for access.

An additional layer of network security is offered to UNIX-type operating systems by Transmission Control Protocol (TCP) wrappers. TCP wrappers are programs that check incoming traffic against host access or access control lists. The first list is in a file named /etc/hosts.allow and includes every IP address or host server authorized for access, while the second, /etc/hosts.deny, is a blacklist. Network services which protect themselves with TCP wrappers are described as “wrapped.” The benefit of TCP wrappers is that they can protect their systems against “spoofing” (falsification) by verifying the names and addresses of new visitors through forward- and reverse-DNS lookups. However, TCP wrappers do not offer data encryption or cryptographic authentication, and most cybersecurity experts believe that they should be used in addition to firewalls rather than as replacements.

Another common criterion of IP banning is the geographic origin of the address being checked. Firewalls can find out this information via Internet geolocation, wherein a lookup tool canvasses public databases to find out where IP addresses are registered. There are legitimate uses for blocking IP addresses on the basis of their owners’ locations—for example, media-streaming services like Netflix use geolocation to prevent customers in one region from accessing content that is only legally available in another—but the practice can also be unfairly discriminatory.

Precisely blocking IP addresses has its challenges. For example, the devices of guests at hotels are dynamically assigned IP addresses, which are then reused. Proxy servers, virtual private networks, anti-detect browsers, and The Onion Router (Tor) all disguise their users’ IP addresses. Many bad actors now use malware to control other computers—and use their IP addresses—without their owners’ knowledge. Users are also well within their rights to obtain a new IP address from their Internet service providers during the process of their DHCP lease renewals. Sometimes, the simple act of restarting one’s router or modem is enough to circumvent a ban, as the network will then assign that device a new address.

Various solutions to these problems exist. If multiple unwanted IP addresses share an IP address prefix, the prefix itself can simply be blocked, albeit at the risk of denying service to innocent users who share it. Many VPN services own a limited number of IP addresses that their subscribers share, so networks can block them by banning IP addresses accessed by multiple users. Proxy servers can be used defensively. Since firewalls are generally sold as products by cybersecurity companies, they are constantly being strengthened with new updates to counter whatever workarounds arise.

Many governments have also buttressed the integrity of IP bans by making their circumvention a criminal or civil offense. Repressive governments that use IP bans to stop their citizens from accessing outside information are obvious examples, but even in the United States, bypassing an IP ban was once considered an offense under the Computer Fraud and Abuse Act.

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