Archive for the ‘NTP GPS time’ Category
London 2012 will be the 30th modern Olympic Games, and in its 116-year history, UY98UZDDVGGJ the Olympics have gone through many changes. New events have been introduced, records have been broken and different cities have played host to the games, but one constant has remained – the need to time competitors accurately during the different events. (more…)
When it comes to network time synchronisation, Network Time Protocol (NTP) is by far the most widely used software protocol. Whether it’s for keeping a network of hundreds or thousands of machines synchronised, or keeping a single machine running true, NTP offers the solution. Without NTP, and the NTP server, many of the tasks we perform on the internet, from shopping to online banking, simply wouldn’t be possible. (more…)
Because accurate and secure time is essential for any computer network finding a time source that is both precise and secure, is an important part of keeping a network healthy. With network time sources, there are plenty of choices, but not all of them can provide the security and precision needed by the modern network. (more…)
Most of us know how useful the GPS network is. The Global Positioning System has changed the way we navigate on the road, and most modern cars are sold complete with some form of satellite navigation system already installed. However, the Global Positioning System is not only useful for satellite navigation; it has other uses too, especially as a source of accurate time for synchronising a computer network and other such technologies with the aid of a GPS network time server.
Need for Synchronisation
Time synchronisation is vital for all sorts of technologies, especially computer networks. Having different machines with a different time can lead to all sorts of untold problems, from data getting lost to simple things such as emails arriving before they were technically sent. Without accurate synchronisation or a network time server, it is nearly impossible to keep a network running smoothly and pinpoint errors and bugs.
Other technologies too need complete synchronicity. CCTV cameras, cash machines and safety systems such as air traffic control all have to be precisely synchronised. Imagine the chaos if your local cash machine told a different time from the one next to it. In effect, you could withdraw money from one machine, while the one next to it would consider a transaction that hadn’t happened yet, allowing you to withdraw the same amount again.
The Global Positioning System doesn’t actually transmit any positioning information. The reason that satellite navigational systems can work out accurate positioning is due to the time signals that the GPS satellites transmit. Onboard each GPS satellite is a couple of atomic clocks. These clocks transmit their times and exact position of the satellite and it’s this information, triangulated from three or more satellites that a navigational system uses to work out exactly where it is in the world.
Atomic clocks have to be used for this process because the signals are travelling at the speed of light. A one-second inaccuracy in the time signal would lead a satellite navigational system to be in error of over 300,000 km. And it’s a testament to the atomic clocks on GPS satellites that most sat nav systems are accurate to within a few metres.
GPS Network Time Server
Because of the accuracy of the GPS time signals, and the fact that the signal are available anywhere on the planet, the GPS network is ideal for use as a master time source for computer network time synchronisation. To synchronise a computer network or other technology systems to GPS time, all that is required is a GPS network time server.
GPS network time servers do all the work for you. By use of a rooftop antenna, the time server receives the GPS signal and distributes it around a network of machines. By use of time synchronisation protocols such as NTP (Network Time Protocol), all devices can be kept within a few milliseconds of the original GPS time source. And you don’t need multiple time servers for large networks either. A single device can synchronise hundreds of devices to GPS time.
GPS network time servers are simple to install, simple to use and can maintain millisecond accuracy for all sorts of technologies. Used by organisations as diverse as stock exchanges, air traffic control and banking systems, GPS time servers provide an efficient and cost effective solution to maintain network synchronicity.
Time is essential to all of us, and losing track of time can be costly. Missing meetings, being late for work or not catching the last bus home can all be a nuisance, but all this pales in comparison to what happens when a computer network loses track of time.
Time is critical for computer systems. It is the only reference a network has for knowing when applications and processes need to be, or have been, done. Alter the network time, allow the clocks to drift or fail to synchronise everything properly and a whole host of problems can arise.
Affects of Time Failure
Firstly, if network time goes wrong, processes and applications due to take place may not happen. This is because if the time is wrong a PC may assume the application has already happened. Secondly, data can easily be lost as timestamps are used in the storing process, and if there is a problem with the time, data may just get dumped. Thirdly, when it comes to debugging a system, without accurate synchronisation it can be nearly impossible. Knowing when something went wrong is essential for any error correction.
Finally, network security is reliant on secure and accurate time. Hackers and malicious software can use any discrepancies in a system’s time to gain access to a network. It only takes a second or two of discrepancy to provide enough access to unauthorised access. And if the time source itself is attacked, the effects can be even more severe
Time Server Security
Many computer networks use online NTP time servers (Network Time Protocol). These are accessed across the internet and send a regular timestamp to which a network synchronises. The problem with these online time server systems is that if the time server is wrong, so the network will be. Also, if a time server itself gets attacked by hackers or malicious software, the effects can be catastrophic. Imagine you network suddenly thinking it’s a year in the future, or in the past, the entire network could be open to all sorts of abuse.
The accuracy of these online time servers can never be guaranteed and are affected by all sorts of things such as the distance away, and the speed of the connection, and they also require an open port in the firewall, through which they send their time signals, and this port could also be used by malicious users.
The NTP Time Server
The solution for ensuring network security is fairly simple and relatively inexpensive – the NTP time server. These dedicated devices receive the time directly from an atomic clock source such as the GPS network (Global Positioning System). This not only makes them highly secure methods of synchronising network time, but also highly accurate, often to within a few milliseconds.
The cost of an NTP server is relatively low, especially when you consider the cost of failing to have accurate and secure network time will cost you. As a single NTP server is able to synchronise a network of hundreds of machines, securely, and offers peace of mind and a cost effective and secure method of keeping your network healthy.
As British summer time officially ended last weekend, with the clocks going back to bring the UK back to GMT (Greenwich Mean Time), the debate about the annual clock changing has started again. The Coalition Government has proposed plans to change the way Britain keeps time by shifting the clocks forward another hour, and in effect reverting to Central European Time (ECT)..
ECT, would mean that Britain would remain an hour ahead of GMT in the winter and two hours ahead in the summer, providing lighter evenings but darker mornings, especially for those north of the border.
However, any proposed plans have stiff opposition from the Scottish Government who suggest that by altering the clocks, many areas in Scotland wouldn’t see daylight during winter until about 10am, meaning many children would have to go to school in the dark.
Other opponents, include traditionalists, argue that GMT has been the basis for British time for over a century, and that any change would be simply … unBritish.
However, a change to ECT would make things easier for businesses that trade with Europe, keeping British workers on a similar timescale to their European neighbours.
Whatever the outcome of the proposed changes to GMT, little will change when it comes to technology and computer networks as they already keep the same timescale all over the globe: UTC (Coordinated Universal Time).
UTC is a global timescale kept true by an array of atomic clocks and is used by all sorts of technologies such as computer networks, CCTV cameras, bank telling machines, air traffic control systems and stock exchanges.
Based on GMT, UTC remains the same the world over, enabling global communication and the transfer of data across time zones without error. The reason for UTC is obvious when you consider the amount of trade that goes on across borders. With industries such as the stock exchange, where stocks and shares fluctuate in price continuously, split second accuracy is essential for global traders. The same is true for computer networks, as computers use time as the only reference as to when an event has taken place. Without adequate synchronisation, a computer network may lose data and international transactions would become impossible.
Most technologies keep synchronised to UTC by using NTP time servers (Network Time Protocol), which continually check system clocks across whole networks to ensure that they all are synced to UTC.
NTP time servers receive atomic clock signals, either by GPS (Global Positioning Systems) or by radio signal broadcast by national physics laboratories such as NIST in the United States or NPL in the UK. These signals provide millisecond accuracy for technologies, so no matter what time zone a computer network is, and no matter where it is in the world, it can have the same time as every other computer network across the globe that it has to communicate with.
Most of us recognise how long an hour, a minute, or a second is, and we are used to seeing our clocks tick past these increments, but have you ever thought what governs clocks, watches and the time on our computers to ensure that a second is a second and an hour an hour?
Early clocks had a very visible form of clock precision, the pendulum. Galileo Galilei was the first to discover the effects of weight suspended from a pivot. On observing a swinging chandelier, Galileo realised that a pendulum oscillated continuously above its equilibrium and didn’t falter in the time between swings (although the effect weakens, with the pendulum swinging less far, and eventually stops) and that a pendulum could provide a method of keeping time.
Early mechanical clocks that had pendulums fitted proved highly accurate compared to other methods tried, with a second able to be calibrated by the length of a pendulum.
Of course, minute inaccuracies in measurement and effects of temperature and humidity meant that pendulums were not wholly precise and pendulum clocks would drift by as much as half an hour a day.
The next big step in keeping track of time was the electronic clock. These devices used a crystal, commonly quartz, which when introduced to electricity, will resonate. This resonance is highly precise which made electric clocks far more accurate than their mechanical predecessors were.
True accuracy, however, wasn’t reached until the development of the atomic clock. Rather than using a mechanical form, as with a pendulum, or an electrical resonance as with quartz, atomic clocks use the resonance of atoms themselves, a resonance that doesn’t change, alter, slow or become affected by the environment.
In fact, the International System of Units that define world measurements, now define a second as the 9,192,631,770 oscillations of a caesium atom.
Because of the accuracy and precision of atomic clocks, they provide the source of time for many technologies, including computer networks. While atomic clocks only exist in laboratories and satellites, using devices like Galleon’s NTS 6001 NTP time server.
A time server such as the NTS 6001 receives a source of atomic clock time from either GPS satellites (which use them to provide our sat navs with a way to calculate position) or from radio signals broadcast by physics laboratories such as NIST (National Institute of Standards and Time) or NPL (National Physical Laboratory).
A day is something most of us take for granted, but the length of a day is not as simple as we may think.
A day, as most of us know, is the time it takes for the Earth to spin on its axis. Earth takes 24 hours to do one complete revolution, but other planets in our solar system have day lengths far different to ours.
The largest planet, Jupiter, for instance, takes less than ten hours to spin a revolution making a Jovian day less than half of that of Earth, while a day on Venus is longer than its year with a Venusian day 224 Earth days.
And if you think of those plucky astronauts on the international Space Station, hurtling around the Earth at over 17,000 mph, a day for them is just 90 minutes long.
Of course, few of us will ever experience a day in space or on another planet, but the 24-hour day we take for granted is not as steadfast as you may think.
Several influences govern the revolution of the Earth, such as the movement of tidal forces and the effect of the Moon’s gravity. Millions of years ago, the Moon was much closer to Earth as it is now, which caused much higher tides, as a consequence the length of Earth’s day was shorter—just 22.5 hours during the time of the dinosaurs. And ever since the earth has been slowing.
When atomic clocks were first developed in the 1950’s, it was noticed that the length of a day varied. With the introduction of atomic time, and then Coordinated Universal Time (UTC), it became apparent that the length of a day was gradually lengthening. While this change is very minute, chorologists decided that to ensure equilibrium of UTC and the actual time on Earth—noon signifying when the sun is at its highest above the meridian—additional seconds needed to be added, once or twice a year.
So far, 24 of these ‘Leap Seconds’ have been since 1972 when UTC first became the international timescale.
Most technologies dependent on UTC use NTP servers like Galleon’s NTS 6001, which receives accurate atomic clock time from GPS satellites. With an NTP time server, automatic leap second calculations are done by the hardware ensuring all devices are kept accurate and precise to UTC.
The media is full of stories of cyber terrorism, state sponsored cyber warfare and internet sabotage. While these stories may seem like they come from a science fiction plot, but the reality is that with so much of the world now dependent on computers and the internet, cyber attacks are a real concern for governments and businesses alike.
Crippling a website, a government server or tampering with systems like air-traffic control can have catastrophic effects—so no wonder people are worried. Cyber attacks come in so many forms too. From computer viruses and trojans, that can infect a computer, disabling it or transferring data to malicious users; distributed denial of service attacks (DDoS) where networks become clogged up preventing normal use; to border gateway protocol (BGP) injections, which hijack server routines causing havoc.
As precise time is so important for many technologies, with synchronisation crucial in global communication, one vulnerability that can be exploited is the online time server.
By sabotaging a NTP server (Network Time Protocol) with BGP injections, servers that rely on them can be told it’s a completely different time than it is; this can cause chaos and result in a myriad of problems as computers rely solely on time to establish if an action has or hasn’t taken place.
Securing a time source, therefore, is essential for internet security and for this reason, dedicated NTP time servers that operate externally to the internet are crucial.
Receiving time from the GPS network, or radio transmissions from NIST (National Institute for Standards and Time) or the European physical laboratories, these NTP servers can’t be tampered with by external forces, and ensure that the network’s time will always accurate.
All essential networks, from stock exchanges to air traffic controllers, utilise external NTP servers for these security reasons; however, despite the risks, many businesses still receive their time code from the internet, leaving them exposed to malicious users and cyber attacks.