NTP or Network Time Protocol to give it its full name is an internet protocol designed to distribute precise time around a network. NTP is a UDP based protocol used to synchronize system time on network infrastructure, such as servers, workstations and network equipment .

This article describes how to utilise the Network Time Protocol authentication features to authenticate time references when synchronizing clients to a NTP Server.

NTP Server Security

Network Time Protocol is used to provide a precise time reference for time critical applications. Therefore, NTP can pose a security risk if malicious users attempt to corrupt a NTP timestamp to create a false time on network equipment.

NTP provides increased security in the form of authentication. Authentication is intended to overcome security risks by ensuring that any response received from an NTP time server has come from the intended reference. The client sends a request for time to a NTP server. The server then responds to the client with a precise timestamp along with one of a number of agreed encrypted keys. On receipt of the timestamp, the client un-encrypts the key and verifies it against a list of trusted keys. The client can then be sure that the received timestamp was indeed transmitted from the intended time reference. NTP utilises MD5 encryption (Message Digest Encryption 5), which is a 128-bit cryptographic hash function, which outputs a fingerprint of the key. MD5 is a highly secure encryption algorithm, widely used on the internet for authentication and security purposes.

NTP Authentication Keys

NTP authentication keys are codes that are encrypted on both the server and client that are used to identify the NTP time server. NTP authentication keys are stored in a file usually called ‘ntp.keys’. Each authentication key consists of a key number, an encryption code and the key itself.

E.g. NTP server keys:

2 M VisioN

5 M SeRvEr

7 M TiMeLy

10 M MYKEY

12 M TiDy

14 M MaGic

The authenication key number acts as a reference to the specified authentication key. The encryption code specifies the type of encryption to be utilised, e.g. ‘M’ for MD5 encryption. The actual keys must be identical on both the client and the NTP time server. The client may utilise a sub-set of the authentication keys specified on the NTP Server. The keys are case sensitive.

E.g. client keys:

5 M SeRvEr

7 M TiMeLy

10 M MYKEY

14 M MaGic

Trusted Authentication Keys

Trusted authentication keys are specified in the NTP server configuration file, ‘ntp.conf’. Trusted keys specify which subset of keys are currently activeand can be used by the NTP server. This allows a sub-set of trusted keys to be selected from a potentially large keys file. The trusted keys specifier allows key references to be changed easily without editing the keys file. Trusted keys are selected using the ‘trusted-keys’ configuration command.

E.g.

trusted-keys 7 10 14

This specifies that authentication keys with the key references of 7, 10 and 14 are trusted and can be used by the NTP installation.

NTP Security Summary

Essentially, authentication is used by the client to authenticate that the NTP server is who he says he is, and that no rogue server intervenes. The key is encrypted and sent to the client by the server where it is unencrypted and checked against the client keys to ensure a match. Authenication provides NTP with a high level of security to prevent malicous tampering of timestamp information.

Today computer has become one of the most inseparable parts of our lives. Most of all people cannot survive without working on computer. It is used in everywhere be it in schools, universities, offices or at homes. But now the computers especially those which have internet connection are not at all secure. There are a number of people who try to serve their malicious business using computer. These people are called hackers. They craft some malicious software which sneak into the computer of innocent people without their knowledge or consent.  The sole intension of them is to scare people and scam their precious money.

If you are a regular computer user and concerned over the security of your PC you should have the necessary security measures such as antivirus and anti-spyware software installed in your system.

Every single day a new virus is being crafted by the hackers and it infects almost 8 out of 10 computers.  Once a PC gets infected with virus it becomes slow and eventually gets damaged. But the more harmful thing is that there are some viruses that can steal all you personal online information and keep your identity at risk. Therefore, it is necessary to install a good antivirus software to prevent such virus attacks.

Apart from virus attacks you have to be careful about the spyware attacks as well. Spyware are more harmful than virus. It is crafted to log your keystrokes and browsing habits to steal all your personal online information such as your bank account or credit card details and sent it to the hacker who has created it. Therefore, it is important to have anti-spyware software than antivirus software.

Moreover, there are lots of hybrid threats which have the features of both spyware and virus. Conficker is the latest example of this kind of hybrid threats. Therefore it will be good for you to install both antivirus and anti-spyware software to ensure the safety of your computer.

If you are looking forward to install proper security measures instead of buying an antivirus software you should buy the security software. It can provide you complete solution and defend both spyware and virus attacks.

So you want to know the 5 secrets Internet Security Tips?

I understand how you feel – in fact my email account was hacked 2 months ago. I noticed that Inernet Security is very critical no matter what programs you use.

Face book is one of the most popular program which most people do use it. It is fun and it allows us to do many things in there with our friends. However, while we are enjoying the fun times with friends, we really don’t want someone hack into our account and ruin it. As a matter of fact, Face Book does aware all the internet security risks, and there are actually things that you can do to protect yourself.

The 5 secret tips will help you and I to solve this problem – make sure you follow it:

1. Make your profile ‘PRIVATE”. You could do under the “Privacy setting tap” in your Facebook. When the “Private” option is on, only your friends that you are accepted will be able to see your photos and walls. This is a way that you could protect from people you don’t know to look at your information.

2. Block people that you don’t want to show your information to. You can simply go to their photograph and there should be a block option for you to choose. When this is activated, this person no longer to be able to see anything that related to your account and this a great options to avoid people that is bothering you.

3. When you block a person, there will be a window pops up and ask you for the reason. You must REPORT them if they have cyber stalking or harassment. It is important to REPORT if this is really happening, because people will not stop if no one reports.

4. Only add people that you really know and this is the best internet security in any ways. By building your list to 1000 of people doesn’t mean you really have a big group of friends. Think what is your purpose for using this Face Book, if you just want to keep on adding people, I am so sure you will not put any personal or photos in here, however, if you are use this as for your friends, then you should stop adding people you don’t know for security reasons.

5. Do not buy anything through Facebook. I know there are lots of applications that you need to pay for, but try to ignore it and use the “FREE” things they offers. It is not clever to give out your financial information to 3rd party just because you want to send a picture of a birthday cake to your friends.

Warning: Do not neglect the above tips!! Be sure to take this advice seriously if you want to protect your own information in Face Book.

On computer problem, many people would say, “I am so familiar with that because my computer always provides me the chance to learn how to fix it all the time!” From slow running speed; pops-up that always ask you to buy certain program; to blue screen some of the time, no one can stand these problems forever! How to fix such computer will be tough for many people since not every one is good at computer. So I would like to provide you some useful tips for solving these problems and sincerely hope they can do you a favor in this way. 

Reduce the quantity of programs while booting computer. Some people do not take it for serious because they think it is not a big deal of setting this. Actually, more programs add to booting list, the slower you computer will operate. To some extent, your computer will be easier to get blue screen because of too many booting programs. It is indeed quite important for maintain your computer. Use an excellent and professional anti-virus program to protect your computer security. This is one of the most effective and easiest ways to keep your computer far away from the malware and other malicious programs. Although there are many anti-virus programs in the software market, you should choose the one which fits your PC the best. For example, you can try Spyware Cease, Avast and so on. Do remember to update the program and scan your system periodically. Delete the unnecessary files in your computer, especially C Disk. For those documents that you seldom use or never use, pick them up and get them out of your PC immediately! This is for saving memory of your computer.

There are also many other useful ways to maintain your computer. You can simply follow the above instructions and keep your computer safe with ease. Or you can visit http://www.spywarecease.com/ and have your computer check now!

There are many hundreds of ways that children may be exploited online by unscrupulous individuals and organized groups. Deep concerns recently are that certain websites use a system of ‘typosquatting’, which is a method of targeting words that are misspelled to capture searches toward a particular direction. Children represent a large target group and many are directed toward pornographic content and websites that deliver  violent and x-rated content.

Language used on inappropriate websites for children deliberately directs in a way that will patronize a child’s street jargon and familiar playground slang. The child’s search may then be picked up and conveyed to a ghastly world of sleaze and unsuitability. Added to these concerns is the real threat posed by the children themselves, who are likely to surf the net in search of material they know to be out of bounds because hey, that is what kids do!

Without parental control of the internet it is possible for children to become involved in web based communities whose sole purpose is to corrupt and coerce children into unsuitable activities. If your child uses a webcam, there is an even greater danger that a close relationship may be developed with an undesirable entity online.

When computers were first introduced into the classroom and the home, the World was delighted to find that children developed an early affinity with the computer screen, soaking up information like sponges and retaining new systems and programs at twice the rate of their adult supervisors. That delight has turned to worry as we begin to appreciate the real dangers posed by unsupervised internet access for our children.

Parents who are genuinely concerned about their child’s well being and who actively seek a way to prevent their child being abused through internet corruption will invest in reliable parental control programs to guarantee their child’s security. Parental control on the internet guarantees that a child has access only to those sites that can do no harm and weeds out the nasty influences that no parent would wish their child to be exposed to.

By using a parental control filter you may effectively block websites that offer products and services of an unsuitable genre and also control the amount of time your child spends browsing the internet through a parental control timer. This will ensure your child is not over exposed to the computer which can lead to a reliance on online social interaction. Material examined may be monitored via a parental control monitor, giving tight parental control and guaranteeing security for your family.


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A wireless home network brings many benefits – all the family can access the Internet simultaneously, you can use a laptop anywhere within the radius of the wireless network, freeing you from physical constraints, you don’t have to string Cat-5 cabling throughout your house (no holes in the wall either!) – but a wi-fi network also brings it’s own set of security problems. The following recommendations itemise the steps which should be taken to improve your wi-fi network’s security.

1. Put the access point in a central position

Wi-Fi signals radiate from the router or access point, so positioning the access device as centrally as possible achieves two objectives. Firstly it ensures that the wi-fi signal will reach all areas in your house, and secondly it will minimize the amount of signal leakage beyond your property. This is important to minimize the chance of drive-by access to your system. If your signal can be accessed by someone in the street, it may be detected and exploited by unscrupulous people, and if your network security is not sufficient, they may even be able to access your confidential information.

2. Enable an Encryption Scheme for devices on your network

All Wi-Fi equipment supports some form of encryption which makes messages sent over a wireless network less likely to be read by an external entity. Available encryption schemes vary, with WEP being the weakest (and oldest) and WPA -  and now WPA2 -  being stronger and better. You can’t mix and match, though, as all wi-fi devices on your network must use the same encryption scheme. WEP may be not as good as the WPA settings, but remember that it’s far better than no encryption at all.

3. Choose new default Usernames and Administrator Passwords

An Access Point or Router is the heart of a home wi-fi network. These come from the factory with default administrator usernames and passwords. Manufacturers set both the account username and password at the factory. The admin account allows a user to enter network addresses and account information. The username is often simply the word admin or administrator. The password is typically blank or consists of the words “admin”, “public” or “password”. Hackers are well aware of these defaults and if you don’t change them, there is a grave danger of leaving your network open to access by a baddie. As soon as you set up your access point or router, change the admin username and password and it’s a good idea to change them on a regular basis, say every 30 to 60 days.

4. Change the default SSID name

Manufacturers of wi-fi access points and routers normally ship their products with a default network name (the SSID). SSID stands for Service Set Identifier, which is a 32-character sequence that uniquely identifies a wireless LAN. In other words, the SSID is the name of the wireless network. In order for a wireless device to connect to a wireless network it must know the SSID of the wireless network in question. If you plug your wireless router or access point in and leave the default SSID, it won’t take long for an attacker to determine what the SSID is. As soon as you configure your access point or router, change the SSID to a unique name that will be difficult to guess.

5. Disable SSID Broadcasting

SSID broadcasting by your access point or router occurs every few seconds and is intended to allow users to find, identify and connect to wi-fi networks. If you have a wireless device, this feature allows you to discover which networks are within range, and what their names are. It’s the first step to connecting to a wi-fi network. This feature is not necessary in a home network, however, and is undesirable since it allows external entities to discover your network’s SSID. It is strongly advised that home network users disable this feature in order to improve the security of your wi-fi network.

6. Enable MAC Address filtering

The functionality known as Media Access Control (MAC) address filtering uses a computer’s physical hardware. Each computer has its own unique MAC address. MAC address filtering allows the network administrator to enter a list of MAC addresses that are allowed to communicate on the network. It also allows the network administrator to deny access to any MAC address not specifically allowed onto the network. This method is very secure, but if you buy a new computer or if visitors to your home want to use your network, you’ll need to add the new machine’s MAC address to the list of approved addresses.

7. Assign Static IP Addresses to Devices

Static IP address assignment (sometimes also called fixed addressing) is an alternative to dynamic addressing (called DHCP) on Internet Protocol networks. Dynamic Host Configuration Protocol (DHCP) is an Internet protocol for automating the configuration of computers that use TCP/IP. DHCP can be used to automatically assign IP addresses to devices connected to your wi-fi network.. Dynamic addressing is convenient. It also allows mobile computers to more easily move between different networks. Unfortunately, this can work to the advantage of hackers, who can get valid IP addresses from your network’s DHCP pool. To avoid this possibility, turn off DHCP on your access point or router and assign a fixed IP address to each device on the network.

8. Enable hardware and software Firewalls on your network

Most routers these days contain built-in hardware firewall capabilities, but it’s also recommended that each computer (PC or laptop) connected to your wi-fi network should have its own personal software firewall installed. A software firewall will protect your computer from intrusion by scanning incoming messages and blocking suspicious traffic from entering your system. It will also prevent unauthorized outgoing messages which may prevent Trojans on your system from sending your valuable information to a hacker.

9. Disable automatic connection to open Wi-Fi networks

If your wi-fi enabled device detects an open (i.e. unsecured) wi-fi network, such as a free wireless hotspot or even a neighbors unsecured network, it may connect automatically without informing you. For example, on Windows XP computers having Wi-Fi connections managed by the operating system, the setting is called “Automatically connect to non-preferred networks.” Once connected, you could be exposing your system to a security risk. Disable all automatic connections, or at least only allow connection once you have been informed and have approved the connection.

10. Shut down your network when you’re not using it

If your wi-fi network isn’t turned on, hackers can’t get to it. This is possibly the very best way to avoid security problems. Of course, if it’s turned off, you can’t use it either… However, consider turning off your wireless system during periods of non-use, such as vacations, if you are away from home on business, or any other periods when you know you won’t be using it.