NETWORKING SECURITY :)

Network security consists of the provisions and policies adopted by a network administrator to prevent and monitor unauthorized access, misuse, modification, or denial of a computer network and network-accessible resources. Network security involves the authorization of access to data in a network, which is controlled by the network administrator. Users choose or are assigned an ID and password or other authenticating information that allows them access to information and programs within their authority. Network security covers a variety of computer networks, both public and private, that are used in everyday jobs conducting transactions and communications among businesses, government agencies and individuals. Networks can be private, such as within a company, and others which might be open to public access. Network security is involved in organizations, enterprises, and other types of institutions. It does as its title explains: It secures the network, as well as protecting and overseeing operations being done. The most common and simple way of protecting a network resource is by assigning it a unique name and a corresponding password.

virus :

A computer virus is a computer program that can replicate itself and spread from one computer to another. The term "virus" is also commonly, but erroneously used, to refer to other types of malware, including but not limited to adware and spyware programs that do not have a reproductive ability.
Viruses can increase their chances of spreading to other computers by infecting files on a network file system or a file system that is accessed by other computers. This is some example of computer virus :

• Adware
• Malware
• Spam
• Spyware
• Computer Worms
• Trojan

                      


cyber crime :

Cyber crime encompasses any criminal act dealing with computers and networks (called hacking). Additionally, cyber crime also includes traditional crimes conducted through the Internet. For example; hate crimes, telemarketing and Internet fraud, identity theft, and credit card account thefts are considered to be cyber crimes when the illegal activities are committed through the use of a computer and the Internet. Type of cyber crime is :

• THEFT OF TELECOMMUNICATIONS SERVICES
• COMMUNICATIONS IN FURTHERANCE OF CRIMINAL CONSPIRACIES
• TELECOMMUNICATIONS PIRACY
• DISSEMINATION OF OFFENSIVE MATERIALS
• ELECTRONIC MONEY LAUNDERING AND TAX EVASION
• ELECTRONIC VANDALISM, TERRORISM AND EXTORTION
• SALES AND INVESTMENT FRAUD
• ILLEGAL INTERCEPTION OF TELECOMMUNICATIONS
• ELECTRONIC FUNDS TRANSFER FRAUD

Hacking :

finding out weaknesses in an established system and exploiting them. A computer hacker is a person who finds out weaknesses in the computer and exploits them. Hackers may be motivated by a multitude of
reasons, such as profit, protest, or challenge. The subculture that has evolved around hackers is often referred to as the computer underground but it is now an open community. While other uses of the word hacker exist that are not related to computer security, they are rarely used in mainstream context. They are subject to the long standing hacker definition controversy about the true meaning of the term hacker. In this controversy, the term hacker is reclaimed by computer programmers who argue that someone breaking into computers is better called a cracker, not making a difference between computer criminals (black hats) and computer security experts (white hats). Some white hat hackers claim that they also deserve the title hacker, and that only black hats should be called crackers. The type of hacker is :

• White hat
• Black hat
• Grey hat
• Elite hacker
• Script kiddie
• Neophyte
• Blue hat
• Hacktivist
• Nation state
• Bots

             

HOW TO PROTECT YOUR COMPUTER ?

- Keep Your Firewall Turned On:

A firewall helps protect your computer from hackers who might try to gain access to crash it, delete information, or even steal passwords or other sensitive information. Software firewalls are widely recommended for single computers. The software is prepackaged on some operating systems or can be purchased for individual computers. For multiple networked computers, hardware routers typically provide firewall protection.

- Install or Update Your Antivirus Software:

Antivirus software is designed to prevent malicious software programs from embedding on your computer. If it detects malicious code, like a virus or a worm, it works to disarm or remove it. Viruses can infect computers without users' knowledge. Most types of antivirus software can be set up to update automatically.

- Install or Update Your Antispyware Technology:

Spyware is just what it sounds like software that is surreptitiously installed on your computer to let others peer into your activities on the computer. Some spyware collects information about you without your consent or produces unwanted pop-up ads on your web browser. Some operating systems offer free spyware protection, and inexpensive software is readily available for download on the Internet or at your local computer store. Be wary of ads on the Internet offering downloadable antispyware in some cases these products may be fake and may actually contain spyware or other malicious code. It's like buying groceries shop where you trust.

- Keep Your Operating System Up to Date:

Computer operating systems are periodically updated to stay in tune with technology requirements and to fix security holes. Be sure to install the updates to ensure your computer has the latest protection.

- Be Careful What You Download:

Carelessly downloading e-mail attachments can circumvent even the most vigilant anti-virus software. Never open an e-mail attachment from someone you don't know, and be wary of forwarded attachments from people you do know. They may have unwittingly advanced malicious code.

- Turn Off Your Computer:

With the growth of high-speed Internet connections, many opt to leave their computers on and ready for action. The downside is that being "always on" renders computers more susceptible. Beyond firewall protection, which is designed to fend off unwanted attacks, turning the computer off effectively severs an attacker's connection be it spyware or a botnet that employs your computer's resources to reach out to other unwitting users.

- Use Strong Passwords :

Setting a strong password on ALL your accounts makes it more difficult for an attacker to gain access to your computer or resources. See Georgetown University's password guidelines for more information about selecting a strong password.

This is 3 type of topology of LAN with advantages and disadvantages. I hope can give some information about this to you all ! ;)

What is a Topology?

The physical topology of a network refers to the configuration of cables, computers, and other peripherals. Physical topology should not be confused with logical topology which is the method used to pass information between workstations. Logical topology was discussed in the Protocol chapter.

Main Types of Physical Topologies :

1. Linear Bus :)

A linear bus topology consists of a main run of cable with a terminator at each end. All nodes (file server, workstations, and peripherals) are connected to the linear cable.

Linear Bus topology

Advantages of a Linear Bus Topology :

• Easy to connect a computer or peripheral to a linear bus.
• Requires less cable length than a star topology.

Disadvantages of a Linear Bus Topology : 

• Entire network shuts down if there is a break in the main cable.
• Terminators are required at both ends of the backbone cable.
• Difficult to identify the problem if the entire network shuts down.
• Not meant to be used as a stand-alone solution in a large building.

2. Star :)

A star topology is designed with each node (file server, workstations, and peripherals) connected directly to a central network hub, switch, or concentrator .Data on a star network passes through the hub, switch, or concentrator before continuing to its destination. The hub, switch, or concentrator manages and controls all functions of the network. It also acts as a repeater for the data flow. This configuration is common with twisted pair cable; however, it can also be used with coaxial cable or fiber optic cable.

Star topology

Advantages of a Star Topology : 

• Easy to install and wire.
• No disruptions to the network when connecting or removing devices.
• Easy to detect faults and to remove parts.

Disadvantages of a Star Topology : 

• Requires more cable length than a linear topology.
• If the hub, switch, or concentrator fails, nodes attached are disabled.
• More expensive than linear bus topologies because of the cost of the hubs.

3. Ring :)

The ring topology connects computers on a single circle of cable. Unlike the bus topology, there are no terminated ends. The signals travel around the loop in one direction and pass through each computer, which can act as a repeater to boost the signal and send it on to the next computer. This shows a typical ring topology with one server and four workstations. The failure of one computer can have an impact on the entire network.A network's physical topology is the wire itself. A network's logical topology is the way it carries signals on the wire

Advantages of Ring Topology : 

1. High performance delivered
2. Token ring technology reduces the need of server or central hub to manage the workstations
3. All nodes have equal opportunity to transmit the data

Disadvantages of Bus Topology :

1. If one node is disrupted then the whole network goes down
2. It becomes difficult to add/remove nodes
3. If more than one token is generated then it may cause ambiguity in the sending of both kinds.

hai ;)
minggu ni nak cite pulakk pasal antivirus software. enjoyy :D

antivirus software :)

   Antivirus or anti-virus software is used to prevent, detect, and remove malware, including but not limited to computer viruses, computer worm, trojan horses, spyware and adware. Computer security, including protection from social engineering techniques, is commonly offered in products and services of antivirus software companies.

   In order to be an effective defense, your antivirus software needs to run in the background at all times, and should be kept updated so it recognizes new versions of malicious software.

example of antivirus :)

1.  Kaspersky Anti-Virus

2.  NOD32 AntiVirus

3.  Clam AntiVirus

4.  McAfee AntiVirus plus

5.  NANO AntiVirus

6.  nProtect

7.  TrustPort AntiVirus

8.  Rising AntiVirus

9.  AVIRA AntiVirus

10.  Norton Antivirus

11.  PANDA Antivirus

12.  AVAST Antivirus

13.  Norman Antivirus

Input Devices

An input device is any hardware device that sends data to the computer, without any input devices, a computer would only be a display device and not allow users to interact with it, much like a TV. In the picture to the right, is a Logitech trackball mouse and an example of an input device. Below is a complete listing of all the different computer input devices that can be used on a computer.Input devices are things we use to put information INTO a computer.

Here are some examples of input devices.

                    Note:  An APPLICATION is a type of computer program.             Some applications are word processing, spreadsheets, databases, and games.

Here are some examples of input devices :

1 . Camera - most cameras like this are used during live conversations.  The camera transmits a picture from one computer to another, or can be used to record a short video.




2. Compact Disc (CD) - CDs store information.  The CD can then be put into another computer, and the information can be opened and added or used on the second computer.
Note:  A CD-R or CD-RW can also be used as an OUTPUT device.

3. Keyboard - The keyboard is a way to input letters or numbers into different applications or programs.  A keyboard also has special keys that help operate the computer.

4. Mouse - The mouse is used to open and close files, navigate web sites, and click on a lot of commands (to tell the computer what to do) when using different applications.

5. Digital Camera - A digital camera can be used to take pictures.  It can be hooked up to a computer to transfer the pictures from the camera to the computer.  Some digital cameras hold a floppy disk, and the floppy disk can be taken out of the camera and put directly into the computer.

6. Drawing Tablet - A drawing tablet is similar to a white board, except you use a special pen to write on it and it's connected to the computer.  Then the word or image you draw can be saved on the computer.

7. Microphone - A microphone is used to record sound.  The sound is then saved as a sound file on the computer.

8. Scanner - A scanner is used to copy pictures or other things and save them as files on the computer. 

9. Disk Drive - A disk drive can hold a CD or a floppy disk.  It reads the information on the disk so that the computer can use it.

10. Joystick - A joystick is used to move the cursor from place to place, and to click on various items in programs.  A joystick is used mostly for computer games.

11. Touch Screen - A touch screen is a computer screen or other screen that you can touch with your finger to enter information.  Examples of touch screens include a smart board, a microwave, a dishwasher, or an ATM at a bank.

12. Bar Code Scanner - A bar code scanner scans a little label that has a bar code on it.  The information is then saved on the computer.  Bar code scanners are used in libraries a lot.

thursday_02/02/12

assalammualaikum ;)

hye all , today aku nak story about advantages and disadvantages of internet kat korang..okey , as we know the Internet is a global system of interconnected computer network that use the standard Internet protocol suite to serve billions of users worldwide..It is a network of networks that consists of millions of private, public, academic, business, and government networks, of local to global scope, that are linked by a broad array of electronic, wireless and optical networking technologies..The Internet carries an extensive range of information resources and services, such as the inter-linked hypertext documents of the World Wide Web (WWW) and the infrastructure to support email..

Antara ADVANTAGES  of internet ni ialah..

information :
Information The biggest benefit offered by the Internet is information. It functions as a valuable resource of information. You can find any type of information on any subject with the help of the search engines like yahoo and google :)

email :
It is very important when you want to send something..Of course you can send not only texts..You can email whatever you want, movies, photos, songs, computer programs..Sending an email is much cheaper then phoning, or sending normal letters :)

shopping :
Along with getting information on the Internet, you can also shop online. There are many online stores and sites that can be used to look for products as well as buy them using your credit card. You do not need to leave your house and can do all your shopping from the convenience of your home :)

online chat :
There are many ‘chat rooms’ on the web that can be accessed to meet new people, make new friends, as well as to stay in touch with old friends :)

downloading software :
This is one of the most happening and fun things to do via the Internet. You can download innumerable, games, music, videos, movies, and a host of other entertainment software from the Internet, most of which are free :)

DISADVANTAGES of internet :

personal information :
If you use the Internet, your personal information such as your name, address, etc. can be accessed by other people. If you use a credit card to shop online, then your credit card information can also be ‘stolen’ which could be akin to giving someone a blank check :)

pornography :
This is a very serious issue concerning the Internet, especially when it comes to young children. There are thousands of pornographic sites on the Internet that can be easily found and can be a detriment to letting children use the Internet :)

spamming :
This refers to sending unsolicited e-mails in bulk, which serve no purpose and unnecessarily clog up the entire system :)

so , that's all je lahh yang aku nak bagi tahu kat korang..hope info yang aku bagi kat korang ni berguna lah yee..ni pon copy from internet je..tapi dah di edit okey :P
wassalamm.. ;)