Germans Enter Race to Build the Worlds Most Accurate Clock

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Following the success of Danish researchers working in conjunction with NIST (National Institute for Standards and Time), who unveiled the world’s most accurate atomic clock earlier this year; German scientist have entered the race to build the world’s most precise timepiece.

Researchers at the Physikalisch-Technische Bundesanstalt (PTB) in Germany are using use new methods of spectroscopy to investigate atomic and molecular systems and hope to develop a clock based around a single aluminium atom.

Most atomic clocks used for satellite navigation (GPS), as references for computer network NTP servers and air traffic control have traditionally been based on the atom caesium. However, the next generation of atomic clocks, such as the one unveiled by NIST which is claimed to be accurate to within a second every 300 million years, uses the atoms from other materials such as strontium which scientists claim can be potentially more accurate than caesium.

Researchers at PTB have opted to use single aluminium atoms and believe they are on the way to developing the most accurate clock ever and believe there is huge potential for such a device to help us understand some of the more complicated aspects of physics.

The current crop of atomic clocks allow technologies such as satellite navigation, air traffic control and network time synchronisation using NTP servers but it is believed the increases accuracy of the next generation of atomic clocks could be used to reveal some of the more enigmatic qualities of quantum science such as string theory.

Researchers claim the new clocks will provide such accuracy they will even be able to measure the minute differences in gravity to within each centimetre above sea-level.

Milestones in Chronology From Crystals to Atoms

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Telling the time may seem a simple affair these days with the number of devices that display the time to us and with the incredible accuracy of devices such as atomic clocks and network time servers it is quite easy to see how chronology has been taken for granted.

The nanosecond accuracy that powers technologies such as the GPS system, air traffic control and NTP server systems (Network Time Protocol) is a long way from the first time pieces that were invented and were powered by the movement of the sun across the heavens.

Sun dials were indeed the first real clocks but they obviously did have their downsides – such as not working at night or in cloudy weather, however, being able to tell the time fairly accurately was a complete innovation to civilisation and helped for more structured societies.

However, relying on celestial bodies to keep track of time as we have done for thousands of years, would not prove to be a reliable basis for measuring time as was discovered by the invention of the atomic clock.

Before atomic clocks, electronic clocks provided the highest level of accuracy. These were invented at the turn of the last century and while they were many times more reliable than mechanical clocks they still drifted and would lose a second or two every week.

Electronic clocks worked by using the oscillations (vibrations under energy) of crystals such as quartz, however, atomic clocks use the resonance of individual atoms such as caesium which is such a high number of vibrations per second it makes the incredibly accurate (modern atomic clocks do not drift by even a second every 100 million years).

Once this type of time telling accuracy was discovered it became apparent that our tradition of using the rotation of the earth as a means of telling time was not as accurate as these atomic clocks. Thanks to their accuracy it was soon discovered the Earth’s rotation was not precise and would slow and speed up (by minute amounts) each day. To compensate for this the world’s global timescale UTC (Coordinated Universal Time) has additional seconds added to it once or twice a year (Leap seconds).

Atomic clocks provide the basis of UTC which is used by thousands of NTP servers to synchronise computer networks to.

Worlds Most Famous Clock Reaches 150

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It’s one of the world’s most iconic land marks. Standing proudly over the Houses of Parliament, Big Ben celebrates its 150th birthday. Yet despite living in an age of atomic clocks and NTP time servers, it is one of the most used timepieces in the world with hundreds of thousands of Londoners relying on its chimes to set their watches to.

Big Ben is actually the name of the main bell inside the clock that creates the quarter hourly chimes but the bell didn’t start chiming when the clock was first built. The clock began keeping time on 31 May 1859, while the bell didn’t strike for the first time until July 11.

Some claim the twelve tonne bell was named after Sir Benjamin Hall the Chief Commissioner of Works who worked on the clock project (and was said to be a man of great girth). Others claim the bell was named after heavyweight boxer Ben Caunt who fought under the moniker Big Ben.

The five-tonne clock mechanism works like a giant wristwatch and is wound three times a week. Its accuracy if in tuned by adding or removing old pennies on the pendulum which is quite far removed from the accuracy that modern atomic clocks and NTP server systems generate with near nanosecond precision.

While Big Ben is trusted by tens of thousands of Londoners to provide accurate time, the modern atomic clock is used by millions of us every day without realising it. Atomic clocks are the basis for the GPS satellite navigation systems we have in our cars they also keep the internet synchronised by way of the NTP time server (Network Time Protocol).

Any computer network can be synchronised to an atomic clock by using a dedicated NTP server. These devices receive the time from an atomic clock, either via the GPS system or specialist radio transmissions.

The NTP Time Server Essential Network Protection

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There are a myriad of hardware and software methods of protecting computers. Anti-virus software, firewalls, spyware and routers to name but a few yet perhaps the most important tools for keeping a network safe is often the most overlooked.

One of the reasons for this is that the network time server’s often referred to as the NTP time server (after the protocol Network Time Protocol) primary task is time synchronisation and not security.

The NTP server’s primary task is to retrieve a time signal from a UTC source (Coordinated Universal Time) which it then distributes it amongst the network, checking the clock on each system device and ensuring its running in synchronisation with UTC.

Here is where many network administrators fall down. They know that time synchronisation is vital for computer security. Without it, errors can not be logged (or even spotted) network attacks can’t be countered, data can be lost and if a malicious user does get into the system it is near impossible to discover what they were up to without all machines on a network corresponding to the same time.

However, the NTP server is where many network administrators think they can save a little money. ‘Why bother?’ ‘They say, ‘when you can log on to an Internet NTP server for free.’

Well, as the old saying goes there is no such thing as a free lunch or as it goes a free source of UTC time. Using internet time providers may be free but this is where many computer networks leave themselves open to abuse.

To utilise an internet source of time such as Microsoft’s, NIST or one of those on the NTP pool project may be free but they are also outside a networks firewall and these is where many network administrators come unstuck.

The World in Perfect Synchronization

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Synchronization is something we are familiar with everyday of our lives. From driving down the highway to walking crowded street; we automatically adapt our behaviour to synchronize with those around us. We drive in the same direction or walk the same thoroughfares as other commuters as failing to do so would make our journey a lot more difficult (and dangerous).

When it comes to timing, synchronisation is even more important. Even in our day to day dealings we expect a reasonable amount of synchronisation from people. When a meeting starts at 10am we expect everybody to be there within a few minutes.

However, when it comes to computer transactions across a network, accuracy in synchronisation becomes even more important where accuracy to a few seconds is too inadequate and synchronisation to the millisecond becomes essential.

Computers use time for every transaction and process they do and you only have to think back to the furore caused by the millennium bug to appreciate the importance computer’s place on time. When there is not precise enough synchronisation then all sorts of errors and problems can occur, particularly with time sensitive transactions.

Its not just transactions that can fail without adequate synchronisation but time stamps are used in computer log files so if something goes wrong or if a malicious user has invaded (which is very easy to do without adequate synchronisation) it can take a long time to discover what went wrong and even longer to fix the problems.

A lack of synchronisation can also have other effects such as data loss or failed retrieval it can also leave a company defenceless in any potential legal argument as a badly or unsynchronised network can be impossible to audit.

Millisecond synchronisation is however, not the headache many administrators assume it is going to be. Many opt to take advantage of many of the online timeservers that are available on the internet but in doing so can generate more problems than it solves such as having to leave the UDP port open in the firewall (to allow the timing information through) not-to-mention no guaranteed level of accuracy from the public time server.

A better and simpler solution is to use a dedicated network time server that uses the protocol NTP (Network Time Protocol). A NTP time server will plug straight into a network and use the GPS (Global Positioning System) or specialist radio transmissions to receive the time direct from an atomic clock and distribute it amongst the network.

Why the Need for NTP

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Network Time Protocol is an Internet protocol used to synchronize computer clocks to a stable and precise time reference. NTP was originally developed by Professor David L. Mills at the University of Delaware in 1985 and is an Internet standard protocol and is used in most network time servers, hence the name NTP server.

NTP was developed to solve the problem of multiple computers working together and having the different time. Whilst, time usually just advances, if programs are running on different computers time should advance even if you switch from one computer to another. However, if one system is ahead of the other, switching between these systems would cause time to jump forward and back.

As a consequence, networks may run their own time, but as soon as you connect to the Internet, effects become visible. Just Email messages arrive before they were sent, and are even replied to before they were mailed!

Whilst this sort of problem may seem innocuous when it comes to receiving email, however, in some environments a lack of synchronisation can have disastrous results this is why air traffic control was one of the first applications for NTP.

NTP uses a single time source and distributes it amongst all devices on a network it does this by using an algorithm that works out how much to adjust a system clock to ensure synchronisation.

NTP works on a hierarchical basis to ensure there are no network traffic and bandwidth problems. It uses a single time source, normally UTC (coordinated universal time) and receives time requests from the machines on the top of the hierarch which then pass the time on further down the chain.

Most networks that utilise NTP will use a dedicated NTP time server to receive their UTC time signal. These can receive the time from the GPS network or radio transmissions broadcast by national physics laboratories. These dedicated NTP time servers are ideal as they receive time direct from an atomic clock source they are also secure as they are situated externally and therefore do not require interruptions in the network firewall.

NTP has been an astronomical success and is now used in nearly 99 per cent of time synchronisation devices and a version of it is included in most operating system packages.

NTP owes much of its success to the development and support it continues to receives nearly three decades after its inception which is why t is now used throughout the world in NTP servers.

Security and Synchronisation

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Security is often the most worried about aspect of running a computer network. Keeping unwanted users out whilst allowing freedom for users to access network applications is a full time job. Yet many network administrators fail to pay any heed to one of the most crucial aspects of keeping a network secure – time synchronisation.

Time synchronisation is not just important but it is vital in network security and yet it is staggering how many network administrators disregard it or fail to have their systems properly synchronised.

Ensuring the same and correct time (ideally UTC – Coordinated Universal Time) is on each network machine is essential as any time delays can be an open door for hackers to slip in undetected and what is worse if machines do get hacked are not running the same time it can be near impossible to detect, repair and get the network back up and running.

Yet time synchronisation is one of the simplest of tasks to employ, particularly as most operating systems have a version of the time protocol NTP (Network Time Protocol).

Finding an accurate time server can sometimes be problematic particularly if the network is synchronised across the internet as this can raise other security issues such as having an open port in the firewall and a lack of possible authentication by NTP to ensure the signal is trusted.

However, an easier method for time synchronisation, being both accurate and secure, is to use a dedicated NTP time server (also known as network time server). An NTP server will take a time signal direct from GPS or from the national time and frequency radio transmissions put out by organisations such as NIST or NPL.

By using a dedicated NTP server the network will become a lot securer and if the worst does happen and the system does fall victim to malicious users then having a synchronised network will ensure it is easily solvable.

How to Synchronise a Computer to an Atomic Clock

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Time synchronisation is often a much underrated aspect of computer management. Generally time synchronisation is only crucial for networks or for computers that a take in time sensitive transactions across the internet.

Time synchronisation with modern operating systems such as Windows Vista, XP or the different versions of Linux is relatively easy as most contain the time synchronisation protocol NTP (Network Time Protocol) or a simplified version at least (SNTP).

NTP is an algorithm based program and works by using a single time source that can be distributed amongst the network (or a single computer) and is constantly checked to ensure the network’s clocks is running accurately.

For single computer users, or networks where security and precision are not primary concerns (although for any network security should be a main issue) then the simplest method of synchronising a computer is to use an internet time standard.

With a Windows operating system this can easily be done on a single computer by double clicking the clock icon and then configuring the internet time tab. However, it must be noted that in using an internet based time source such as or windows.time, a port will have to be left open in the firewall which could be taken advantage of by malicious users.

For network users and those not wanting to leave vulnerabilities in their firewall then the most suitable solution is to use a dedicated network time server. Most of these devices also use the protocol NTP but as they receive a time reference externally to the network (usually by way of GPS or long wave radio) the leave no vulnerabilities in the firewall.

These NTP server devices are also far more reliable and accurate than internet time sources as they communicate directly with the signal from an atomic clock rather than being several tiers (in NTP terms known as strata) from the reference clock as most internet time sources are.

Leap Second Errors and Configuration

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Apart from the usual celebrations and revelry the end of December brought with the addition of another Leap Second to UTC time (Coordinated Universal Time).

UTC is the global timescale used by computer networks across the world ensuring that everybody is keeping the same time. Leap Seconds are added to UTC by the International Earth Rotation Service (IERS) in response to the slowing of the Earth’s rotation due to tidal forces and other anomalies. Failure to insert a leap second would mean that UTC would drift away from GMT (Greenwich Meantime) – often referred to as UT1. GMT is based on the position of the celestial bodies so at midday the sun is at its highest above the Greenwich Meridian.

If UTC and GMT were to drift apart it would make life difficult for people like astronomers and farmers and eventually night and day would drift (albeit in a thousand years or so).

Normally leap seconds are added to the very last minute of December 31 but occasionally if more than one is required in a year then is added in the summer.

Leap seconds, however, are controversial and can also cause problems if equipment isn’t designed with leap seconds in mind. For instance, the most recent leap second was added on 31 December and it caused database giant Oracle’s Cluster Ready Service to fail. It resulted in the system automatically rebooting itself on New Year.

Leap Seconds can also cause problems if networks are synchronised using Internet time sources or devices that require manual intervention.  Fortunately most dedicated NTP servers are designed with Leap Seconds in mind. These devices require no intervention and will automatically adjust the entire network to the correct time when there is a Leap Second.

A dedicated NTP server is not only self-adjusting requiring no manual intervention  but also they are highly accurate being stratum 1 servers (most Internet time sources are stratum 2 devices in other words devices that receive time signals from stratum 1 devices then reissue it) but they are also highly secure being external devices not required to be behind the firewall.

The NTP Server Time Synchronisation Made Easy

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Time synchronisation is often described as a ‘headache’ by network administrators. Keeping computers on a network all running the same time is increasingly important in modern network communications particularly if a network has to communicate with another network running independently.

For this reason UTC (Coordinated Universal Time) has been developed to ensure all networks are running the same accurate timescale. UTC is based on the time told by atomic clocks so it is highly precise, never losing even a second. Network time synchronisation is however, relatively straight forward thanks to the protocol NTP (Network Time Protocol).

UTC time sources are widely available with over a thousand online stratum 1 servers available on the Internet. The stratum level describes how far away a time server is to an atomic clock (an atomic clock that generates UTC is known as a stratum 0 device). Most time servers available on the Internet are in fact not stratum 1 devices but stratum in that they get their time from a device that in turn receives the UTC time signal.

For many applications this can be accurate enough but as these timing sources are on the Internet there is very little you can do to ensure both their accuracy and their precision. In fact even if an Internet source is highly accurate the distance away form it can cause delays int eh time signal.

Internet time sources are also unsecure as they are situated outside of the firewall forcing the network to be left open for the time requests. For this reason network administrators serious about time synchronisation opt to use their own external stratum 1 server.

These devices, often called a NTP server, receive a UTC time source from a trusted and secure source such as a GPS satellite then distribute it amongst the network. The NTP server is far more secure than an Internet based time source and are relatively inexpensive and highly accurate.