We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is the Network Time Protocol?

By Kurt Inman
Updated May 17, 2024
Our promise to you
WiseGeek is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At WiseGeek, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

The Network Time Protocol is a means of precisely synchronizing time between multiple computers on a network. Most computer clocks lose at least a full second of time every day, which is not that important to the average user. Many security and event-logging systems must track computers on several networks including the Internet. These systems rely on clock synchronization of their linked computers with the Network Time Protocol. This protocol frequently updates the exact time on its clients from servers which maintain the international atomic time standard.

Also known by the acronym NTP, the Network Time Protocol was first established as a standard in the late 1980s. Several revisions were made throughout the 1990s to improve authentication, algorithms, precision and external synchronization. In 2010, NTP Version 4 was proposed by the Internet Engineering Task Force (IETF) in Request For Comments (RFC) 5905. Version 4 includes public-key cryptography, nanosecond time precision and a method of locating a time server automatically. It also includes improved algorithms and accuracy as well as support for new hardware reference clocks and operating systems.

A user on a small local network may only be mildly annoyed when email or file modification timestamps are out of order. Networks with many users and shared resources on the Internet will be significantly affected by this, however. For financial transaction databases, industrial control applications and network monitoring software, accurate time is usually critical, not only on the system recording the transaction, but on all computers reporting data, 24 hours a day. The Network Time Protocol and the international time servers which support it can address these needs.

A network administrator could update the time daily on each client manually from a time server. Systems can also be configured to reload the time on each reboot. Time drift from hour to hour is significant, however, due to many factors including temperature and operating system issues. The best solution is usually to automatically reset each clock in very small increments multiple times a day with the Network Time Protocol. Using this method, systems and users are not "surprised" by relatively large, sudden leaps forward or backward in time.

A client using the Network Time Protocol can obtain the accurate time from an Internet-based server or a hardwired external time source. Ultimately, both sources get the Coordinated Universal Time (UTC) from an international time server. A hardwired source may receive it directly or indirectly via a special radio signal. A network source usually obtains it indirectly through several layers of servers running NTP software. While there are only a few time servers wired directly to atomic clocks, tens of thousands of servers worldwide relay the time to local systems.

Network time-related software running on each NTP client keeps its clock updated with extreme accuracy and regularity. When a client is not connected to the Internet, the NTP algorithms estimate the current time based on past performance. Systems which do not need the full capabilities of NTP can use a stripped-down version called the Simple Network Time Protocol (SNTP).

WiseGeek is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Discussion Comments

By anon240829 — On Jan 16, 2012

A user on a small local network may only be mildly annoyed when email or file modification timestamps are out of order. Networks with many users and shared resources on the Internet will be significantly affected by this, however.

For financial transaction databases, industrial control applications and network monitoring software, accurate time is usually critical, not only on the system recording the transaction, but on all computers reporting data, 24 hours a day. The Network Time Protocol and the international time servers which support it can address these needs.

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.