NTP POE wall clocks use Network Time Protocol (NTP) to maintain accuracy and synchronisation. NTP is a computer algorithm that works by taking a single master time source that it distributes to all devices on a network. In the case of most NTP systems, the time is received via a NTP time server that is hooked up to a computer network.
There are various solutions for synchronised office clocks, suitable for use in offices of all sizes, even those spread out across the country. The simplest solution is to use atomic clock radio receiver clocks. These come with either digital or analogue displays and they use radio transmissions to receive a source of atomic clock time (UTC – Coordinated Universal Time).
The big advantage of a digital network wall clock is that they never have to be set as the time is kept and maintained by the network time server, which ensure the wall clock is accurate to the millisecond. Furthermore, most digital network wall clocks use the power over Ethernet system to provide the clock’s power, so there is no need to wire them up to the mains or install batteries
Network time servers are responsible for providing a network’s time. Of course, all computers have their own onboard clocks built into the motherboards, but these devices are only cheap oscillators and are prone to drift. When you have a network of hundreds or even thousands of PCs and devices, if there was no synchronisation to a single network time source, all the machines could be relaying completely different times, often several minutes apart.
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.
Perhaps the safest and most accurate means of obtaining a time source is by utilising the time codes transmitted by the GPS (Global Positioning System). All that is required for picking up these GPS signals is a GPS NTP server, which will not only receive the time code, but also distribute it around the network, check for drift and maintain stable and precise time on all machines.
When a network loses time, you are at risk of losing far more than just what time of day it is. Time is an essential aspect of network security and any errors in a network time server can lead to catastrophic result. However, the solution for ensuring network security is fairly simple and relatively inexpensive – the NTP time server.
With so much automated in the modern world and with computer networks running everything from finance to health services, keeping, storing and transferring information needs to be secure, accurate and reliable.
The time is crucial for computer systems to ensure this. Timestamps are the only information computers have to assess if a task has been completed, is due, or that information has been successfully received, sent or stored. One of the most common causes of computer errors comes from inadequate synchronisation of timings.
All computer networks need to be synchronised, and not just all the devices on a network, either. With so much global communication these days, all computer networks across the globe need to be synchronised together, otherwise when they communicate errors may occur, data can get lost, and it can pave the way for security problems as time discrepancies can be used by malicious users and software.
But how do computers synchronise together? Well, it is made possible by to innovations. The first is the international timescale, UTC (Coordinated Universal Time), kept true by atomic clocks and the same the world over, regardless of time-zones. The second, NTP (Network Time Protocol) is a computer program designed to keep PCs synchronised together.
Both NTP and UTC operate in tandem. The computer time server (NTP server) receives a UTC time source, either from radio, GPS (Global Positioning System) or the internet (although an insecure method of receiving UTC and not recommended).
NTP then distributes this time around a network, checking the time on each device at periodic intervals and adjusts them for any drift in time. Most computer networks that utilise NTP time servers in this way have each machine on the network within milliseconds of UTC time, enabling accurate and precise global communication.
NTP time servers are the only secure and accurate method of computer network synchronisation and should be used by any computer system that requires reliability, accuracy and security.
Network Time Protocol (NTP) is a TCP/IP protocol developed when the internet was in its infancy. It was developed by David Mills of the University of Delaware who was trying to synchronise computers across a network with a degree of precision.
NTP is a UNIX based protocol but it has been ported to operate just as effectively on PCs and a version has been included with operating systems since Windows 2000 (including Windows 7, Vista and XP).
NTP, and the daemon (application) that controls it, is not just a method of passing the time around. Any system running the NTP daemon can act as a client by querying the reference time from other servers or it can make its own time available for other devices to use which in effect turns it into a time server itself. It can also act as a peer by collaborating with other peers to find the most stable and accurate time source to use.
One of the most flexible aspects of NTP is its hierarchical nature. NTP divides devices into strata, each stratum level is defined by its proximity to the reference clock (atomic clock). The atomic clock itself is a stratum 0 device, the closest device to it (often a dedicated NTP time server) is a stratum 1 device whilst other devices that connect to that become stratum 2. NTP can maintain accuracy to within 16 stratum levels.
Any network that needs to be synchronised, has to first identify and locate a time source for NTP to distribute. Internet sources of time are available but thee are often taken from stratum 2 devices that operate through the firewall. The only way NTP can peer the time is if the TCP/IP port is left open to allow the traffic through. This could lead to security issues as malicious users can take advantage of this firewall hole.
Dedicated NTP time servers find a source of time via GPS or radio signals and so don’t leave a network vulnerable to attack. By attaching a NTP time server to a router and entire network of hundreds and even thousands of devices can be synchronised thanks to NTP’s hierarchical structure.
Synchronization of computer networks is something that many administrators take for granted. Dedicated network time servers can receive a time source and distribute it amongst a network, accurately, securely and precisely.
However, accurate time synchronization is only made possible thanks the time protocol NTP – Network Time Protocol.
NTP was developed when the internet was still in its infancy and Professor David Mills and his team from Delaware University were trying to synchronise the time on a network of a few machines. They developed the very earliest rendition of NTP which has continued to be developed to this very day, nearly thirty years after its first inception.
NTP was not then, and is not now, the only time synchronisation software, there are other applications and protocol that do a similar task but NTP is the most widely used (by far with over 98% of time synchronisation applications using it). It is also packaged with most modern operating systems with a version of NTP (usually SNTP – a simplified version) installed on the latest Windows 7 operating system.
NTP has played an important part in creating the internet we know and love today. Many online applications and tasks would not be possible without accurate time synchronization and NTP.
Online trading, internet auctions, banking and debugging of networks all rely on accurate time synchronisation. Even sending an email requires time synchronisation with email server – otherwise computers would not be able to handle emails coming from unsynchronised machines as they may arrive before they were sent.
NTP is a free software protocol and is available online from NTP.org However, most computer networks that require secure and accurate time mostly use dedicated NTP servers that operate external to the network and firewall obtaining the time from atomic clock signals ensuring millisecond accuracy with the world’s global timescale UTC (Coordinated Universal Time).