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NTP servers, like most systems are open to abuse and misuse. NTP servers can be flooded with traffic (a distributed denial of service - DDoS attack), the server’s access policy could be violated or the NTP rules of engagement drawn up to prevent misuse of time servers could be breached.

The abuse of NTP servers has received much attention of late due primarily to the case of D-link and a Danish Stratum 1 NTP server run by Poul-Henning Kamp. Mr Kamp noticed a huge rise in traffic to his time server, which at the time was the only Danish stratum 1 server available to the general public.

He discovered that up to 90 percent of the traffic was coming from D-Link router products that were latching on to his stratum 1 server for a time reference.

Normally only stratum 2 servers should connect to stratum 1 server and perhaps some servers where applications require more precision than that of a normal computer network, which can receive its time code via a multitude of sources.

In many countries, timekeeping services are provided by a government agency (such as NPL in the UK or NIST in the US). As there is no Danish equivalent, Kamp provided his time service to the general public in return his ISP agreed to provide a free connection the assumption that the bandwidth involved would be relatively low. With the increased traffic caused by the D-Link routers, his ISP then requested Kamp pay for the extra bandwidth.

D-Link is a Taiwanese based company that manufactures wireless and Ethernet products for the home and small office environment. Whilst not a deliberate attempt at sabotage Kamp’s time server D-Link routers were configured to directly query over 40 stratum 1 servers.

The disagreement lasted fro nearly six months where in 2006 D-Link and Kamp announced they had come to an agreement and D-Link have reconfigured their new routers but little can be done about the existing products out there.

A new defense has subsequently been added to NTP which responds to an authorized request with a packet explicitly requesting the client server stops requesting. This packet has been dramatically called the Kiss-of-death - KOD.

Unfortunately the new requirements of the NTP protocol do not work retrospectively, and old clients and implementations do not recognize KoD it and at the moment there are not any technical means to counteract the misuse of NTP servers.

Adware or advertising-supported software is any software package which automatically plays, displays, or downloads advertising material to a computer after the software is installed on it or while the application is being used. Adware in this form does not operate surreptitiously or mislead the user, and provides the user with a specific service, but Adware and spyware are similar to viruses in that they can be malicious in nature.

Adware has been criticized because it usually includes code that tracks a user’s personal information and passes it on to third parties, without the user’s authorization or knowledge. Adware or advertising-supported software is any software application in which advertisements are displayed while the program is running.

The main reason why Adware is built into programs is because it helps recover programming development costs, and helps to hold down the price of the application for the user (sometimes even making it free of charge) and, of course, it can give programmers a profit, which helps to motivate them to write, maintain, and upgrade their software.

Adware companies make their money by distributing thousands upon thousands of ads on the internet. Adware is considered a legitimate alternative offered to consumers who do not wish to pay for software. It is now big business and there is a lot of money to be made.

Adware is also known as malware, sneakware, or spyware, adware is a type of software program that’s installed without a users consent or knowledge while another program is being installed on the computer. Adware is related to spyware, in that they both invade your computer through software that usually is installed without the user’s consent or knowledge.

Spyware
Spyware is considered a malicious program and is similar to a Trojan Horse in that users unwittingly install the product when they install something else. Spyware can even change computer settings, resulting in slow connection speeds, different home pages, and loss of Internet or other programs.

Spyware can exploit this design to circumvent attempts at removal. Spyware can also come bundled with shareware or other downloadable software, as well as music CDs. Normally it does not directly spread in the manner of a computer virus or worm: and generally, an infected system does not attempt to transmit the infection to other computers.

Spyware, which interferes with networking software commonly, causes difficulty connecting to the Internet. Spyware, along with other threats, has led some Windows users to move to other platforms such as Linux or Apple Macintosh, which are significantly less susceptible. Spyware programs which redirect network traffic cause greater technical-support problems than programs which merely display ads or monitor users’ behavior, and so may more readily attract institutional attention.

Software
Software authors that use spyware do not care about anyone’s privacy. Software designers get paid big bucks to design things that work effectively and safely. The software that is supported by advertising is often called “adware”.

Software developers are now very sensitive to malware concerns and will provide a lengthy explanation of just why the bundled software is necessary, in the cases when they actually do need to use bundled software.

Spyware is computer software that is installed surreptitiously on a personal computer to intercept or take partial control over the user’s interaction with the computer, without the user’s informed consent. Since they tend not to install software if they know that it will disrupt their working environment and compromise their privacy, spyware deceives users, either by piggybacking on a piece of desirable software such as Kazaa, or by tricking them into installing it (the Trojan horse method).

Some “rogue” anti-spyware programs masquerade as security software, while being spyware themselves. The distributor of spyware usually presents the program as a useful utility-for instance as a “Web accelerator” or as a helpful software agent. In some cases, spyware authors have paid shareware authors to bundle spyware with their software. Some spyware authors infect a system through security holes in the Web browser or in other software. The spyware author would also have some extensive knowledge of commercially-available anti-virus and firewall software.

Windows
Windows Defender is free and therefore should be a part of your desktop anti-spyware collection. If you have an adware infected computer Windows may take longer to load, hyperlinks may not work or they may even take you to a new site. Many spyware components would also make use of flaws in Javascript, Internet Explorer and Windows to install without the user’s knowledge or permission.

Malware
Malware is software designed to infiltrate or damage a computer system without the owner’s informed consent. Malware includes computer viruses, worms, trojan horses, so it’s software that damages your system, causes instability, or exhibits antisocial behavior such as changing settings or interfering with a computer’s registry and security settings. Malware writers began to design their programs so that they would reinstall automatically if removed, sometimes using different file names.

Conclusion
If you want your computer to be a stable safe, clean environment then do a Google search for “adware” you will find a great free product called ad-aware, this is one product that I have used for years to keep my computer safe and it’s a product I highly recommend.

Have you sighted our new Web? We netted it on the Inter surf.

The mice go where the action is. We know they curse over the small soft things like excel, word and outlook and use their launching pad to get to the Explorer. Once there, with the Cyber Pages heralding their arrival, they refresh themselves frequently with their favourites and google around for a better connection.

When they find a site they like they take small bytes and click left and right. A bunch of Genius Mice found our new site yesterday and clicked so loudly we could not hear the other surfers coming in by the wave to score hits.

Once, there was such a crowd that a collision took place. Of course they were trapped on the wrong side of the firewall in the collision domain for far too long and their screams broke the MHz barrier. They were taken to the NAP and immediately Ethernet, the anesthetic of choice, had to be administered to push them beyond the baseband gateways into unconsciousness so that the surgeons could commence building backbone.

They are highly communicative and sentimental and they message each other frequently. When they meet a prospective mate, they can be observed spending entire romantic evenings blissfully involved with what is commonly called parallel port and, for those with stamina, multiport repeaters! They wrap their long tails around each other and, if the bandwidth is satisfactory they can be quite productive. Once their multiplexing has taken place, it is usually fruitful and a little later the motherboard becomes creative and another one comes along.

Then they DE or discard eligibility in favour of DNA testing, for their protocol and sense of responsibility is faultless and can be rated highly. They actually measure their amplitude using the base 10 system and their final datagram is placed high up on bricks for all to see.

Our mice have other hobbies, for example, some are bit part actors, and others write bios about the more enterprising and spectacular of their species.

Some of the mice got together and tried to form a musical group but unfortunately it did not work owing to the fact that all of them were bass players; there was 10Base5, 10Base2, 10BaseT, and 100BaseT; this was a string quartet like no other. However, we did hear later that all of them had recently been released from the collision domain and were still quite high on Ethernet!

It was further reported that at this time, owing to the anaesthesia levels not dropping quickly enough, these mice became confused as to where they lived and kept changing addresses and showing up at the wrong houses. It was then that the ARP or Address Resolution Protocol was introduced. This was done out of necessity because the mice are so moral and it was causing embarrassment. So each house was given a different coloured application layer. One good thing came out of this; they began to appreciate their own architecture.

Then get back to us with serious critique; your honest opinion. We’re always up for a little quality control and this time, your candour might just get you a high score and win you something; more than applause that is!

Whether there is spam on the main menu, or you are blogging or profiling, navigate your way to our domain; you’ll be at home with us.

It is a question that has perplexed philosophers and scientists since the dawn of man, ‘what exactly is time?’ and it has only been in our recent history that we have started to discover answers, thanks to Einstein and his work on special and general relativity.

We now know time is not the abstract concept we first thought it was, we also know it is not constant and is relative to different observers throughout the universe with the speed of light being the only constant in the universe.

In other words if the speed of light has to be the same for everybody then someone travelling at close to such a speed would find time slow down.

Fortunately as all humans live within the boundaries of the planet Earth it means the passing of time is very similar for us all (or so minutely different as to be impossible to measure). However, technologies such as satellites and GPS systems have to take into account this altering state of time otherwise they would become wholly inaccurate.

As humans have progressed, telling the time with ever increasing accuracy has become more and more important. Historically, knowing the time was not so imperative. People needed to know the correct day to plant crops or when sunrise and sunset happened but accuracy was not a preoccupation.

However, since the invention of the mechanical clock followed at the turn of the twentieth century by electronic clocks, humans have started to rely on more and more accuracy for their technologies.

Seafaring, aviation and now space travel mean that humans have sought more and more accurate ways of keeping time.

In the 1950’s atomic clocks were developed which were so accurate it was discovered that the revolution of the Earth, something we had based our timescale on for centuries, was no where near as accurate as these new clocks.

Now technologies such as the Internet, the Global Positioning System and satellite communication requires absolute precision as light can travel 300,000 km every second meaning accuracies of a split second could mean our satellite navigation systems could be out by thousands of miles and computer trading would be nigh on impossible.

Fortunately a global time scale, UTC (Coordinated Universal Time), has been developed and is based on the time told by atomic clocks. This allows systems all over the world to be synchronised to the exact same time.

Computer networks use the NTP protocol (Network Time Protocol) to receive a UTC timing reference and synchronise all machines on a network to that time.

NTP servers can receive a time reference over the Internet (although not very secure) from a national radio transmission (as long as the receiver is within range of a suitable transmission) or from the GPS network (via a rooftop GPS antenna).

Network Time Protocol (NTP) is an Internet standard protocol designed over 25 years ago and still under constant development. NTP synchronises devises on a network to a single timing source. If time on a network is not synchronised when applications are conducted over the Internet unintended results can occur such as email being received before it was sent or time sensitive applications failing.

NTP uses a single reference clock to synchronise all clocks on a network to that time. UTC time (Coordinated Universal Time) is the world’s official time standard and most NTP servers are synchronized to receive UTC time. UTC time is kept accurate by a constellation of atomic clocks which ensure that all UTC timing references tell the same time.

NTP is organized into a hierarchy. At the top of the hierarchy are the atomic reference clocks, these are known as stratum 0. Below this strata are servers that receive a timing reference directly from a stratum 0 source. Stratum 2 servers receive time from a stratum 1 server and so on.

NTP is highly scalable meaning a synchronisation network may consist of several reference clocks and NTP will select the best candidates to build its estimate of the current time. This makes NTP highly accurate, with precision of a few hundred nano-seconds not unheard of (nano = 1 second every billion years!)

To synchronise a computer clock to timing reference using NTP extremely simple to do with modern operating systems. Most operating system manufacturers install a version of NTP into their systems (albeit a scaled down version, known as SNTP in some).

This means to connect to an Internet stratum 1 time server a user merely has to insert the domain address in the NTP program. This can be done quite simply in windows by double clicking the system clock and opening up the Internet Time tab. On UNIX the ntp.conf file contains the DNS details.

It should be mentioned that Microsoft, amongst others, recommend using an external hardware source as a timing reference as Internet sources cannot be authenticated leaving a network open to malicious attacks.

An external NTP server can receive a UTC timing signal either through a specialist national radio broadcast (so long as the receiver is within range of a suitable transmission) or from the GPS network (via a GPS antenna).

NTP servers are relatively low cost and easy to install and setup, providing accuracy and precision whilst also offering security.

There are a lot of ways to repair a scratched DVD. Temporary fixes are quick and easy but don’t last for very long while more permanent fixes take a little more time and effort but pay off in the long-run. What you need to decide is whether you want to repair that DVD just so you can play it right now or if you want to play it again later in the future. This article will cover the quickest fixes so that you can be up and running in a few minutes.

If you want that DVD running quickly then your best bet is “wax” the surface. Applying a thin layer of Vaseline on the plastic buffer will sometimes help the laser eye to see through to the data underneath. Another commonly used product is furniture polish. What you’re doing is filling in the scratches on the DVD in order to make it easier for your player to read. I would not recommend using these methods to repair a scratched DVD if you want to continue to use that DVD later on.

There are a lot of suggestions out there on how to repair a scratched DVD but not all of them work (or are worth trying). Filling in the scratches with Banana, for example, is not a great idea. The last thing you want is bits of Banana or other stuff in your DVD player. Use common sense.

Many of the best ways to repair a scratched DVD use polishing as a method of making scratches appear more shallow. This is an ideal solution but doing it manually can cause more damage then you originally had. No matter what material you use to polish manually, whether its toothpaste or Brasso, the job is doomed to be uneven and will eventually destroy the DVD altogether.

If you want to repair a scratched DVD for some time to come then you are better off just biting the bullet and buying an automated system. I’ve lost several DVD’s to toothpaste or furniture polish but never to an automated system. I even bought one for my home so that I can just fix my DVDs minutes before I play them. It’s the quickest way, it guarantees perfect results, and fixing even two movies pays back the investment.

Nowadays, abbreviations and emotions are used in online communications such as MSN instant messenger, emails and many more. Abbreviations or acronyms, such as BTW for “by the way,” are commonly used to save time in all types of communications. They are being used with increased frequency in text messaging and e-mail exchanged via wireless phones, since text entry is slow using just a phone key-pad.

Emotions - also sometimes called smiley - allow people to add an emotional tone to written online communications. Without these symbols, it is sometimes difficult to tell if a comment is serious or a joke, since you cannot see the individual’s face or hear his or her tone of voice.

Most people would agree that these abbreviations and symbols are fine to use with personal and casual communications but they are not usually viewed as appropriate for formal business communications.

Here are some of the common acronyms used in online communications.

Common Chat Acronyms:

A

AFAIK - “As far as I know”

AKA - “Also known as”

ASAP - “As soon as possible”

ASL - “Age, sex and location”

B

b/c - “Because”

b4 - “Before”

BFF - “Best friends forever”

BRB - “Be right back”

BTW - “By the way”

C

CTN - “Can’t talk now”

cya - “See ya”

CYE - “Check your email”

D

DIY - “Do it yourself”

dl - “Download”

E

ETA - “Estimated arrival time”

F

FYI - “For your information”

G

gb - “Goodbye”

GG - “Good Game”

gr8 - “Great”

GTG - “Got to go”

H

HOAS - “Hold on a second”

HTH - “Hope this helps”

I

IAC - “In any case”

IC - “I see”

IDK - “I don’t know”

IIRC - “If I remember correctly”

IMHO - “In my humble opinion”

IMO - “In my opinion”

J

JK - “Just kidding”

JC - “Just curious”

K

k - “Ok”

L

L8 - “Late”

L8r - “Later”

LMK - “Let me know”

LOL - “Laughing out loud”

M

MSG - “Message”

MYOB - “Mind your own business”

N

N/A - “Not available”

NC - “No comment”

NP - “No problem”

O

OMG - “Oh my gosh/god”

P

pls - “Please”

ppl - “People”

pwn - “Own”

Q

qt - “Cutie”

R

ROTFL - “Rolling on the floor laughing”

S

sup - “What’s up”

T

TBC - “To be continued”

TC - “Take care”

thx - “Thanks”

TTYL - “Talk to you later”

U

UR - “Your/You are”

W

w/e - “Whatever”

w/o - “Without”

W8 - “Wait”

X

XOXO - “Hugs and kisses”

Y

y - “Why”

YW - “You’re welcome”

Z

ZZZ - “Sleeping”

Emotions:

Smile

Frown

Wink

Laugh

Sticking out tongue

:-> Sarcastic

>:-< Angry

<:-) Dumb

:-S Kind of like it

:-O Surprise

(@@) You’re kidding!

((H)) Big hug

Bookmark this list of e-mail and instant messaging acronyms for future reference!

Press Control-D (PC) / Command-D (Mac) to add this page to your bookmarks.

Don’t you find it annoying that whenever you are in a middle of research or online surfing, the connection suddenly stops? If you’ve experienced that a number of times, perhaps the problem might lie with the cable modem. And what you can do perform a few tweaks on the cable modem in order to optimize its operation.

Say the cable modem on your computer gets disconnected after a few minutes, then here’s a cable modem tweak that can help you address the issue. One reason this thing happens in your computer is that this is Windows XP-related. On the Windows XP, there is an option that allows the computer to turn off the USB device in order to save on power. Now what you can do is to disable this option. Just click on the start button and highlight the My Computer icon and select the option that says properties. A window will then appear with the system properties. Navigate the window by clicking on the hardware tab and press the device manager button. Expand the serial bus controllers and double click on the USB root hub. You’ll now see the Power Management tab and uncheck the ‘allow the computer to turn off the device to save power’. If the computer displays a number of USB root hub, then make sure that you repeat the same steps for that same number of hubs. Often a cable modem that disconnects after a few hours can be remedied by performing these two steps. One cable modem tweak that is possible is by disabling the hibernation. You can right click on the desktop and click the screen saver tab. You’ll notice the power button of the display properties dialog. Click that one. Another dialog box will appear and you’ll be shown the hibernate tab. Use this box to uncheck the box beside the enable hibernation. Another good step is to disable the Windows Messenger. On the start button, select run and input the words gpedit.msc. Proceed to the Computer Configuration then select the Administrative Templates, then straight to Windows Components and on to Windows Messenger. Don’t run the messenger, just go to the properties and check the box near it to enable.

Another thing that computer users can do is to configure the modem delay time. This is true usually to Motorola and Rockwell modems. And this issue always happens right after the user has installed the Windows 2000 drivers on the XP Pro. In order to address the problem, here’s a little tweak that you can do. But as a precaution, make sure that you back up your registry even if there will be no problems. Again, click on the run and type the words ‘regedit’. Then you have to select the HKEY current user/remote access/profile/”your isp”. Then you to need to change the value of the disconnect idle time from 14 to zero. Following these simple steps can address the issue of internet disconnection every few hours. For a specific cable modem tweak, then a talk with the technical representative of the company can bring results.

Atomic clocks have been with us for over fifty years now and most people have heard of them and know they are very accurate, but how accurate are they and why do we need such accurate clocks?

Atomic clocks are used by many of us even if we are not aware of it. The time they tell is relayed around the world and picked up by time servers using the protocol NTP to synchronise networks, they are vital for lots of technologies, such as global satellite navigation, and TV signal timings.

Before the development of the atomic clock the most precise timekeeping devices were electronic clocks which would lose a second or two every week. These had largely replaced mechanical clocks which were less accurate still.

Mankind has always had a fascination for keeping track of the time but knowing the precise time has never been too important. A second or even a minute’s difference does not affect our day-to-day lives.

However, as technology has advanced the need for more precise timekeeping has increased. Satellites that have to be navigated and communicate with the Earth from hundred, thousands and even millions of miles away require exact timing. Light and therefore radio waves can travel 300,000 km every second so slight inaccuracies in time can have massive differences.

The first accurate atomic clock was built y Britain’s National Physical Laboratory in 1955 by Dr Louis Essen who based his clock around the oscillation of the caesium -133 atom. The idea was actually first conceived as far back as 1879 when Lord Kelvin proposed that time-keeping based on how atoms behaved would be a better way to count time intervals than anything else.

The first generation of atomic clocks (also known as caesium oscillators) used the frequency of this atom which oscillates 9,192,631,770 times every second. Essen’s model was accurate to a second every 300 years but developments of the caesium oscillator mean they can now achieve accuracies of one second every 80 million years.

Yet as technologies get more advanced, scientists strive to make better and more accurate clocks. Rubidium standard clocks offer no better accuracy than caesium models but are smaller and cost less (caesium oscillators are generally only to be found in large-scale physics laboratories).

Clocks using just a single atom have been developed that offer even more accuracy. A clock based on a single mercury atom has achieved accuracies of one second in 400 million years and it is expected that a new type of strontium clock that uses light will go even better.

The future for atomic clocks is ever increasing accuracy combined with scaling down the size and cost of them. The American National Institute of Standards and Technology (NIST) have unveiled a chip-sized atomic clock that boasts millisecond accuracy.

Atomic clocks are now part and parcel of our lives without the time signals they transmit to the world that are picked up by NTP servers modern communication from Internet shopping and GPS and technological advances such as satellite navigation would become impossible.

H.264 or MPEG-4 Part 10 (Advanced Video Coding) is an industry standard for video compression, this is the process of converting digital video into a format that can achieve very high data compression. So far Motion JPEG and MPEG-4 part 2 are the compression standards that are widely used in surveillance industry. With the use of H.264 video compression codec, surveillance industry could see a drastic change in the way CCTV systems are used. With the use of H.264 video compression codec surveillance equipment could see itself taking a major leap in terms of usage of storage space, better image quality and transmission of video.

Video compression codec H.264 involves encoding and decoding processes. The video encoder performs the process of encoding and transforming the video to H.264 bit stream and in turn the decoder decodes the bit stream and delivers the original content. If you are interested in complete process of how H.264 works please visit the resources listed below. The whole process is very accurate and reduces storage space by more than 50% without compromising on the image quality when compared to Motion JPEG and MPEG-4 Part 2. It also delivers same quality if not better images per bit rate when compared to MotionJPEG/MPEG-4 Part 2.

By using the video encoders which support H.264, an analog system can be integrated into more efficient and powerful IP based video surveillance system. This enables the system to deliver better image quality with higher resolutions, frame rates and multiple streaming capabilities, decreased bandwidth and storage requirements. Video analytical applications can be used with the converted video increasing effective usage and management of large-scale video systems such as big shopping malls etc. The use of H.264 modeled systems will have a greater advantage in surveillance industry in the near future and will encourage the use of Megapixel cameras whose biggest challenges are requirement of large storage space and huge usage of network bandwidth.