The NTP pool is a dynamic collection of networked computers that volunteer to provide highly accurate

time Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. It is a component quantity of various measurements used to sequence events, t ...

via the Network Time Protocol to clients worldwide. The machines that are "in the pool" are part of the ''pool.ntp.org''

domain Domain may refer to: Mathematics *Domain of a function, the set of input values for which the (total) function is defined ** Domain of definition of a partial function **Natural domain of a partial function **Domain of holomorphy of a function *Do ...

as well as of several

subdomain In the Domain Name System (DNS) hierarchy, a subdomain is a domain that is a part of another (main) domain. For example, if a domain offered an online store as part of their website example.com, it might use the subdomain shop.example.com . O ...

s divided by

geographical zone The five main latitude regions of Earth's surface comprise geographical zones, divided by the major circles of latitude. The differences between them relate to climate. They are as follows: # The North Frigid Zone, between the North Pole at 90 ...

and are distributed to NTP clients via

round-robin DNS Round-robin DNS is a technique of load distribution, load balancing, or fault-tolerance provisioning multiple, redundant Internet Protocol service hosts, e.g., Web server, FTP servers, by managing the Domain Name System's (DNS) responses to ...

. Work is being done to make the geographic zone selection unnecessary via customized authoritative DNS servers that utilize

geolocation software In computing, Internet geolocation is software capable of deducing the geographic position of a device connected to the Internet. For example, the device's IP address can be used to determine the country, city, or ZIP code, determining its geogra ...

. , the pool consists of 3,126 active servers on

IPv4 Internet Protocol version 4 (IPv4) is the fourth version of the Internet Protocol (IP). It is one of the core protocols of standards-based internetworking methods in the Internet and other packet-switched networks. IPv4 was the first version d ...

and 1,534 active servers on

IPv6 Internet Protocol version 6 (IPv6) is the most recent version of the Internet Protocol (IP), the communications protocol that provides an identification and location system for computers on networks and routes traffic across the Internet. I ...

. Because of the

decentralization Decentralization or decentralisation is the process by which the activities of an organization, particularly those regarding planning and decision making, are distributed or delegated away from a central, authoritative location or group. Conce ...

of this project, accurate statistics on the number of clients cannot be obtained, but according to the project's website, the pool provides time to 5–15 million systems. Because of client growth, the project is in perpetual need of more servers. The more time servers there are in the pool, the lower the resource demand on each member. Joining the pool requires at least a

broadband In telecommunications, broadband is wide bandwidth data transmission which transports multiple signals at a wide range of frequencies and Internet traffic types, that enables messages to be sent simultaneously, used in fast internet connections. ...

connection to the Internet, a static

IP address An Internet Protocol address (IP address) is a numerical label such as that is connected to a computer network that uses the Internet Protocol for communication.. Updated by . An IP address serves two main functions: network interface ident ...

, and accurate time from another source (for example, another NTP server, a

DCF77 DCF77 is a German longwave time signal and standard-frequency radio station. It started service as a standard-frequency station on 1 January 1959. In June 1973 date and time information was added. Its primary and backup transmitter are located ...

receiver, a

WWVB WWVB is a time signal radio station near Fort Collins, Colorado and is operated by the National Institute of Standards and Technology (NIST). Most radio-controlled clocks in North America use WWVB's transmissions to set the correct time. The 70 ...

receiver, or a

GNSS receiver A satellite navigation device (satnav device) is a user equipment that uses one or more of several global navigation satellite systems (GNSS) to calculate the device's geographical position and provide navigational advice. Depending on the s ...

). This project was started by Adrian von Bidder in January 2003 after a discussion on comp.protocols.time.ntp about abuse of the public stratum 1 servers. The system has been maintained and developed by Ask Bjørn Hansen since July 2005."The Future is Bright, The Future is ..."
Adrian 'Dagurashibanipal' von Bidder. July 24, 2005.

References

External links

* {{Internet-stub

Pool Pool may refer to: Water pool * Swimming pool, usually an artificial structure containing a large body of water intended for swimming * Reflecting pool, a shallow pool designed to reflect a structure and its surroundings * Tide pool, a rocky pool ...

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