Difference between revisions of "IP address"
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==IP versions== | ==IP versions== | ||
| − | IP version 4 is currently used by most network devices. However, with increasing numbers of electronic devices accessing the internet, available IPv4 addresses have been essentially depleted. IPv4 uses 32-bit numeric strings which limits it to 4,294,967,296 possible addresses. | + | IP version 4 is currently used by most network devices. However, with increasing numbers of electronic devices accessing the internet, available IPv4 addresses have been essentially depleted. IPv4 uses 32-bit numeric strings which limits it to 4,294,967,296 possible addresses. To help extend its functionality, [[network address translation]] is often used to connect many devices through only a few (often just one) public addresses. IPv4 addresses can theoretically range from <code>0.0.0.0</code> to <code>256.256.256.256</code>, although there are reserved sets, including <code>0.x.x.x</code>, <code>10.x.x.x</code>, <code>127.x.x.x</code>, and <code>192.168.x.x</code>. The highest possible value for each octet (256) is also no available for normal usage, so 255 is the highest value which can be assigned. |
| − | IP version 6 is the replacement for the aging IPv4. This protocol theoretically offers 2^128 (340,282,366,920,938,463,463,374,607,431,768,211,456) unique addresses.<ref name="What is My IP">http://www.whatismyip.com/faq/what-is-an-ip-address.asp</ref><ref>https://royal.pingdom.com/the-number-of-possible-ipv6-addresses-read-out-loud/</ref> However, RFC 2374 (obsoleted by RFC 3587) has limited the valid IPv6 addresses to about 2^125 at this time. Additionally, some addresses will be reserved for special purposes, and for various other reasons, not all of these theoretical addresses will but usable.<ref>https://rednectar.net/2012/05/24/just-how-many-ipv6-addresses-are-there-really/</ref> | + | IP version 6 is the replacement for the aging IPv4. This protocol theoretically offers 2^128 (340,282,366,920,938,463,463,374,607,431,768,211,456) unique addresses.<ref name="What is My IP">http://www.whatismyip.com/faq/what-is-an-ip-address.asp</ref><ref>https://royal.pingdom.com/the-number-of-possible-ipv6-addresses-read-out-loud/</ref> However, RFC 2374 (obsoleted by RFC 3587) has limited the valid IPv6 addresses to about 2^125 at this time. Additionally, some addresses will be reserved for special purposes, and for various other reasons, not all of these theoretical addresses will but usable.<ref>https://rednectar.net/2012/05/24/just-how-many-ipv6-addresses-are-there-really/</ref><br /> |
| − | With IPv6, the amount of possible IP addresses is increased exponentially, allowing for | + | With IPv6, the amount of possible IP addresses is increased exponentially, allowing for a much greater increase in the use of mobile phones, computers, video game consoles, tablet computers, [[Internet of things|IoT]] devices, and even computers found within modern automobiles. IPv6 can also justify for the future growth in [[world population]] of [[Earth|Planet Earth]].<br /> |
| + | IPv6 addresses use 64-bits, so the addresses use [[hexadecimal]] values. | ||
==Tracking== | ==Tracking== | ||
| − | |||
| − | IP address tracking | + | ===Geolocation=== |
| + | IP addresses map to specific devices around the world, and those addresses are leased to them by their service providers.Since the service providers know the exact physical address of each customer, IP addresses can technically be traced to the device's physical location. Publicly available tools are able to get some idea of a device's location based based solely on its address. However, these tools are often limited to the knowledge of what internet service provider owns the relevant IP block, and the ISP's location. They generally only attempt to determine the state and town of origin, although these estimations can be significantly inaccurate. Sometimes the reported "geolocation" of an IP address will be the network switch nearest to the IP user, and sometimes it will only be able to report several steps back from this.<br /> | ||
| + | Despite these common inaccuracies, Geolocation can still be used by advertising companies (to advertise based on your approximate location), stalkers and and cyber criminals. IP addresses are not at all secret, so they can be fairly easy to obtain. Any direct communication discloses the user's IP address, and sometimes it is published openly. For example, a [[Wikipedia®]] article "edit history" page that reveals the IP address of editors who did not log into user accounts.<br /> | ||
| + | This same basic technique can be used by the webmasters of major websites such as [[YouTube]] and [[Facebook]] to help law enforcement track down a criminal. IP address tracking can play a vital role in law enforcement, such as to track down and prosecute hackers, child molesters, stalkers, and even potential terrorists. Law enforcement agencies typically have the significant benefit of being able to obtain from ISPs (by warrant or subpoena) the exact physical address to which the IP address is registered. | ||
==See also== | ==See also== | ||
Revision as of 21:26, May 19, 2019
An IP ("Internet Protocol") address is a unique identification number used by networked electronic devices. Each device has a unique IP address (or is behind a NAT router which does) on the Internet, which is used much like a mailing address. All communications sent to a specific device must list that device's IP address, and all communications from that device must include its source address.
Static vs dynamic
IP addresses cannot be randomly chosen by a device; that device must be assigned an address by the network it is connecting to. This address can be assigned as either static or dynamic. Static IP addresses are permanently assigned to a specific device. This is helpful when external devices need to initiate contact with that device (such as a web server receiving a visitor). Dynamic IP addresses are issued by a DHCP server from a pool of IP addresses for a limited time, when devices request them. When a device's dynamic IP address expires, it is either renewed, or the device is assigned a new one.
IP versions
IP version 4 is currently used by most network devices. However, with increasing numbers of electronic devices accessing the internet, available IPv4 addresses have been essentially depleted. IPv4 uses 32-bit numeric strings which limits it to 4,294,967,296 possible addresses. To help extend its functionality, network address translation is often used to connect many devices through only a few (often just one) public addresses. IPv4 addresses can theoretically range from 0.0.0.0 to 256.256.256.256, although there are reserved sets, including 0.x.x.x, 10.x.x.x, 127.x.x.x, and 192.168.x.x. The highest possible value for each octet (256) is also no available for normal usage, so 255 is the highest value which can be assigned.
IP version 6 is the replacement for the aging IPv4. This protocol theoretically offers 2^128 (340,282,366,920,938,463,463,374,607,431,768,211,456) unique addresses.[1][2] However, RFC 2374 (obsoleted by RFC 3587) has limited the valid IPv6 addresses to about 2^125 at this time. Additionally, some addresses will be reserved for special purposes, and for various other reasons, not all of these theoretical addresses will but usable.[3]
With IPv6, the amount of possible IP addresses is increased exponentially, allowing for a much greater increase in the use of mobile phones, computers, video game consoles, tablet computers, IoT devices, and even computers found within modern automobiles. IPv6 can also justify for the future growth in world population of Planet Earth.
IPv6 addresses use 64-bits, so the addresses use hexadecimal values.
Tracking
Geolocation
IP addresses map to specific devices around the world, and those addresses are leased to them by their service providers.Since the service providers know the exact physical address of each customer, IP addresses can technically be traced to the device's physical location. Publicly available tools are able to get some idea of a device's location based based solely on its address. However, these tools are often limited to the knowledge of what internet service provider owns the relevant IP block, and the ISP's location. They generally only attempt to determine the state and town of origin, although these estimations can be significantly inaccurate. Sometimes the reported "geolocation" of an IP address will be the network switch nearest to the IP user, and sometimes it will only be able to report several steps back from this.
Despite these common inaccuracies, Geolocation can still be used by advertising companies (to advertise based on your approximate location), stalkers and and cyber criminals. IP addresses are not at all secret, so they can be fairly easy to obtain. Any direct communication discloses the user's IP address, and sometimes it is published openly. For example, a Wikipedia® article "edit history" page that reveals the IP address of editors who did not log into user accounts.
This same basic technique can be used by the webmasters of major websites such as YouTube and Facebook to help law enforcement track down a criminal. IP address tracking can play a vital role in law enforcement, such as to track down and prosecute hackers, child molesters, stalkers, and even potential terrorists. Law enforcement agencies typically have the significant benefit of being able to obtain from ISPs (by warrant or subpoena) the exact physical address to which the IP address is registered.