Rabu, 03 Oktober 2012

Definition Web server

A Web server  is a program that, using the client/server  model and the World Wide Web's Hypertext Transfer Protocol (HTTP), serves the files that form Web pages to Web users (whose computers contain HTTP clients that forward their requests). Every computer on the Internet that contains a Web site must have a Web server program. Two leading Web servers are Apahe , the most widely-installed Web server, and Microsoft's Internet Information Server ( IIS ). Other Web servers include Novell's Web Server for users of its NetWare operating system and IBM's family of Lotus Domino servers, primarily for IBM's OS/390 and  AS/400 customers.

The Ubuntu Installation Guide

I hope my guide makes installing Ubuntu an enjoyable, simple experience. By the end of the guide you should have a dual boot Windows / Ubuntu machine that happily plays music, video, and acts as a perfectly usable home office computer with Openoffice 3.0. For the really adventurous you could even run Windows XP inside Virtualbox, which is linked to later on in the guide.  The Ubuntu OS is unique and seriously cool, so, enjoy the trip.

1) Download the Ubuntu ISO from http://www.ubuntu.com/getubuntu/download and save to your desktop
2) Burn the ISO image to a blank CD using Roxio CD creator or similar:

















3) Run the CD from “My Computer” – the CD should ask permission to run at which point you’ll see this option screen:


















Install Ubuntu with Wubi

4) If you’d like to instal Ubuntu using Wubi , select “install inside Windows” and follow the instructions. Installing with WUBI is ideal for a first taste of Ubuntu as you can remove from add/remove programs in Windows later on. This install process is really easy but you don’t get the same performance as if Ubuntu had a separate partition running on its EXT3 file system. The following screens are all based on the Wubi installer process, so you can follow the rest of the instructions below.
If you’d like to install Ubuntu separately to Windows, then skip to point 7) below.
Here’s what you see next:


















If you’ve got the space on your hard drive, go for 30gb or more for the installation size.

5) Now configure your installation using the simple settings options. You can specify the location of the Ubuntu installation on your Windows partition, the size of the Ubuntu installation, the Ubuntu flavour (Ubuntu, Kubuntu, Xubuntu, etc), your preferred language, and a username and password for the Ubuntu system.
When you click install, you’ll see this screen:


















As soon as the files have finished downloading, you’ll see this:


















6) That’s it! Click reboot now, and select “Ubuntu” on the startup screen. You now have a fully functional dual boot Windows / Ubuntu machine.

Install Ubuntu on a single (EXT3) partition (separately to Windows)
7) Click “Demo and full installation” and your computer will restart and boot into Ubuntu.
It’s worth saying at this point that you’re about to install Ubuntu on an entirely separate drive partition. That means, you need to make sure you have enough space on your computers hard drive to accomodate the new setup. Keir Thomas found that a partition less than 4gb would lead Ubuntu to crash during install in his first look at Ubuntu 9.04 over at Lifehacker.
Here’s a guide on how to resize or shrink your Windows Vista partition. Follow those instructions before you reboot into the live version of Ubuntu and you’ll have a really easy time during the following steps. Maybe you’d like to install from a USB? Let’s have a quick look at the process of installing from a USB before we continue:

Here’s how to install Ubuntu on a USB drive from Windows Vista:

8) Format your USB stick with a FAT32 partition from Windows. You can get to the format dialogue by opening My Computer and right mouse clicking the removable drive icon. Click “Format” and follow the settings in the image below. You need a minimum 2gb USB stick.






















9) Download UnetBooting . UNetbootin allows for the installation of various Linux/Ubuntu distributions to a partition or USB drive, so it’s no different from a standard install, only it doesn’t need a CD. The coolest thing about the application is that it’s a “portable” app. You don’t need to install it into Windows meaning UNetbootin will run on your Windows PC without “admin” privileges.


















The new version of Ubuntu isn’t in the Distribution list supplied with UNetbootin yet, so use the downloaded Ubuntu ISO from earlier on. Add the ISO using the “Diskimage”, make sure your USB drive is selected below and click OK.
The ISO transfers to the USB pretty quickly, so soon after you click OK you’ll see this screen:

















10) That’s it – when the installation process is complete, restart your computer and make sure it’s set up to boot from USB. On my HP Laptop, pressing F9 on the boot screen shows a boot order menu. Selecting “USB Hard Drive” follows a black screen, an Ubuntu logo, and finally, your new Ubuntu desktop appears.

Completing your Ubuntu installation, step by step

Installing Ubuntu is so easy that it requires very little effort past this point. If you’ve managed to repartition your hard drive and restart your computer you’ll sail through the next few steps:
11) Click “install” on the live desktop (top left)















12) Choose your language in the welcome screen

















13) Choose your location

















14) Choose your keyboard layout

















15) Set up your disk partition. This is probably the most “technical” part of the installation. When I shrunk my Windows Vista drive volume , I never formatted the new partition, which means the “use the largest continuous free space” option works nicely:






















16) Choose your username and password:

















17) Migrate your Windows documents and settings

















 18) You’re now ready to install your new Ubuntu installation

















19) When the installation has finished, restart your computer (you’ll be instructed to remove your cd rom or USB drive). You’re now ready to begin using Ubuntu!

Useful tips and resources for Ubuntu    (^_^)

Antivirus Software

All security software is not created equal. Like all consumer products, antivirus software has the good, the bad and the mediocre. The choices for antivirus protection are many and varied. We feature the best antivirus software available today from a number of providers and compare them. When it really comes down to it, effectiveness and usability can either make or break antivirus software. Our top-ranked antivirus software combine optimal security with user-friendly features and tools.
Below are the criteria TopTenREVIEWS uses to evaluate and compare antivirus software:
Scope of Protection
While most security solutions tout multi-layered protection and 360-degree defense, some are more thorough than others. The best antivirus solutions will include traditional protection from viruses, worms, Trojans and spyware, but should also include defense from keyloggers, phishing scams, email-borne threats and rootkits. While antivirus programs are by no means full-blown internet security suites, they should protect from as many threats on as many fronts as they can.
Effectiveness
Antivirus is specifically designed to protect your computer, so if it doesn’t do that well, what good is it? All the features, bells and whistles and sleek interfaces can’t make up for poor performance. We look at results from the industry-standard security software testers and professional security organizations to find the most effective software available.
Ease of Installation and Setup
Security software shouldn’t be a chore to install and should have you protected as soon as possible. From download to install, to the first scan, implementing antivirus software should be quick and easy.
Ease of Use
Antivirus software is complex stuff, but shouldn’t require a degree in computer security. The best security programs have all the features security experts want, but are just as easiy for a beginner. Everyday computer users want a security solution that they can install and forget about; software that doesn’t require constant maintenance or have annoying interruptions. The best antivirus software is flexible enough to do exactly what you want to (even if that means running by itself).
Features
A well-rounded feature set takes a security solution from good to great. More than bells and whistles, added features provide security, usability and performance benefits.
Updates
Security software is only as good as its latest update. Viruses are being identified and added to signature databases all the time. So it’s important that your virus definition list updates accordingly. Modern antivirus software are equipped with automatic updates that perform regularly enough that you get faster updates that don’t slow down your system. The best security providers push updates to you as soon as they’re available.
Help & Support
The best software doesn’t require reading an in-depth manual to use, but still has one available. For specific questions, troubleshooting and additional help, the best antivirus manufacturers provide superior product support online and off. Additional support for software may come in the form of assistance over the phone, email, live chat or through a number of additional resources (knowledgebase, FAQs, tutorials).
A well-balanced antivirus solution is effective, efficient and easy to use. Combining all the right features with a usable interface, our top antivirus software choices deliver the best security and usability without a serious investment in time, money or system resources.

9 Best Free Antivirus Programs

1.AVG Anti-Virus Free

 Anti-Virus Free from AVG is the best free antivirus software available. AVG Anti-Virus Free is a full-fledged antivirus and antispyware tool, includes an email scanner, link scanner, scheduled scanning options, automatic updates, and more. There is no need to pay for an antivirus program when the best free antivirus software in the world is just a download away.
AVG Anti-Virus Free works on Windows 7, Windows Vista, Windows XP and Windows 2000.
The huge number of premium features, frequency of updating, and install-it-and-forget-it aspect of AVG's Anti-Virus Free really do make it the best of the best free antivirus programs available today

2. Avast! Free Antivirus

AVAST Software's avast! Free Antivirus most certainly deserves to be on any list of the best free antivirus programs. avast! Free Antivirus has fully functioning antivirus and antispyware engines protecting your PC from threats from the Internet, your files, emails, and even instant messages.
avast! Free Antivirus supports Windows 7, Windows Vista, Windows XP and Windows 2000.
One big reason I included avast! Free Antivirus as a best free antivirus program is because of its "heuristics engine" which can detect previously unknown viruses and other malware. I also like the fact that AVAST has been making this antivirus product since 1988 and is often cited as the most installed antivirus product.
Tip: During the avast! installation, you're asked to install the free Google Chrome browser. It's not required so if you're not interested just uncheck the box. Also, you are required to register avast! to use it more than 30 days but registration is free and pretty simple. You'll also have to reregister once per year - again, for free.

3. Microsoft Security Essentials 


threats: if the icon next to y
Security Essentials from Microsoft is definitely one of the best free antivirus programs available right now. Microsoft is relatively new to the antivirus game but don't let that scare you - Security Essentials is a fantastic antivirus program that protects you from all sorts of malware, updates automatically, and is incredibly easy to use.
Microsoft Security Essentials supports Windows 7, Windows Vista and Windows XP.
Two of the biggest reasons I added Microsoft Security Essentials to this list of the best free antivirus software is because it's directly from Microsoft and also because it's very easy to see if you're computer is secure from our clock is green, you're in good; if it's red, something is wrong.

4. Comodo Antivirus

Comodo Antivirus from Comodo Security Solutions is another excellent program, easily one of the best free antivirus options out there. As of this writing, Comodo Antivirus bills itself as the "Best Antivirus on the Market. Guaranteed." due to its proprietary Defense+ technology. Comodo Antivirus also protects you from several threat sources, just as most of the other best free antivirus programs on this list do.
Comodo Antivirus works on Windows 7, Windows Vista and Windows XP.
Comodo Antivirus is easily one of the best free antivirus solutions solely because of its Defense+ technology that, by default, assumes unknown files are threats instead of safe. That sounds like it might cause problems but Comodo Antivirus utilizes some other technologies to make the whole process silent but still very effective.

5. Avira Antivir Personal 

Avira AntiVir Personal protects you from viruses, Trojans, worms, spyware, adware, and various other kinds of malware, making it a fully functional antimalware tool and certainly one of the best free antivirus programs.
Avira AntiVir Personal works on Windows 7, Windows Vista, Windows XP and Windows 2000. Avira also makes a version of AntiVir Personal for UNIX.
The scope of malware that Avira AntiVir Personal can keep you safe from is alone enough to make it one of the best free antivirus software programs but the heuristics and ease of use add to its value too. The only things I didn't like about Avira AntiVir Personal was the configuration you have to complete after installation which might be difficult if you're a computer novice.
Tip: You're asked to register during the Avira AntiVir Personal installation but it's optional. Just uncheck the box and continue with the install.

6. Panda Cloud Antivirus

Panda Cloud Antivirus protects you from several kinds of malware threats - viruses, worms, Trojans, adware, and more - just like all the other free antivirus programs in this list.
What makes Panda Cloud Antivirus one of the best free antivirus programs is that it does its job from "the cloud" meaning the hard antivirus work that typically slows down a computer is done on computers elsewhere on the Internet, freeing up your computer to work like it should and protecting you from malware even better.
Panda Cloud Antivirus supports Windows 7, Windows Vista and Windows XP.
Tip: Panda Cloud Antivirus tries to install a toolbar and set Yahoo! as your browser's home page during the installation process so uncheck the boxes before continuing if you don't want them. Neither are required to use Panda Cloud Antivirus.

7. Immunet Protect FREE 

Immunet Protect FREE is a unique, cloud-based antivirus program, much like Panda Cloud Antivirus. Immunet Protect FREE protects your computer from bots, worms, viruses, Trojans, keyloggers, and spyware.
Immunet Protect FREE works on Windows 7, Windows Vista and Windows XP. You must also be connected to the Internet at all times.
I think Protect FREE from Immunet is one of the best free antivirus programs for several reasons: you never have to update it, it has completely free telephone based support, and it can be run alongside some of the other best free antivirus tools like AVG Anti-Virus Free, Microsoft Security Essentials, and avast! Free Antivirus, increasing your overall protection!

8.  Digital-defender Antivirus

digital-defender Antivirus isn't a popular antivirus program but it should be. It's certainly one of the best free antivirus software programs you'll find. It's a full antivirus and antispyware program and updates on a daily basis.
digital-defender Antivirus supports Windows 7, Windows Vista and Windows XP.
The relatively small installation size, daily virus definition updates, and full antispyware features make digital-defender Antivirus one of the better tools in my collection of the best free antivirus programs.

9. PC Tools Antivirus Free 

PC Tools AntiVirus Free offers basic protection against viruses and other malware. While not my favorite, AntiVirus Free is still one of the best free antivirus programs you'll find.
PC Tools AntiVirus Free works on Windows 7, Windows Vista and Windows XP.
The biggest problems I have with PC Tools AntiVirus Free are the reminders throughout the program that there's a not-so-free version that you should upgrade to. To be fair, you probably won't notice it since the program runs silently in the background to protect you from viruses. I probably find it annoying because most of the features available in the upgrade are included for free in some of the higher rated best free antivirus programs above.

Types of computer virus
















There are all types of computer viruses but what is a computer virus? A computer virus has been defined as a set of computer instructions that reproduces itself and it may attach to other executable code. Usually this code is a short program that may either embed in other code or stand on it's own. In essence, this computer program is designed to infect some aspect of the host computer and then copy itself as much and as often as it has the chance.

It was estimated that a virus by the name of mydoom infected well over a quarter a million computers in one day back in 2004. There are tens of thousands of worms and viruses now being spread via the internet with new ones being discovered each and every day. It is often through quite innocuous and normal internet activities like the exchange of files like music, photos and others that many people are infected with these unwanted and sometimes dangerous programs.

The nomenclature that is now used to describe viruses has changed considerably over the last few years as more, if not most, computers are now on the internet. This has ushered in a change in the types of computer viruses toward a worm/virus hybrid and has caused the distinction between them to vanish.

There are a whole group of people that spend a tremendous amount of time looking for what have been termed backdoors into your computer so they can find ways to inject their code into your computer and use it for their own intentions.
How Does A Virus Spread

One of the intents of all types of computer viruses that gets installed on your computer will be to spread itself. This happens in a fashion that is not all that different from what happens with a virus in the human population. It is through exposure that the virus spreads when the computers defenses are down or non existent. Also like their biological counterpart the computer virus can be spread rapidly and are not very easy to get rid of.

Because the way a virus operates is to be stealthy, coupled with the rapid communications that happen between today’s computers, it is easy to dramatically increase the speed at which a virus that is targeting a newly discovered vulnerability can move around the web and around the world.

A virus that targets a network of computers can even more easily spread since so many computers are connected and most likely will have the same vulnerability and easy access to one another. Often viruses will spread via shared folders, email or over other media that is often exposed to other computers via removable media like cds and flash drives.

Because there are so many types of computer viruses, a virus can infect another computer unintentionally anytime that program is run and the virus is activated. Something like opening a email attachment or downloading a file off the internet or giving or receiving a copy of a program or file from a co-workers thumb drive can expose you and others to a computer virus.

Literally the gamut of these types of computer viruses can expose you whenever you have a downloaded file or a external drive attached to your pc. The most common way they spread is via email attachments or with the use or transfer of files via instant messaging.

The Types Of Computer Viruses

There are six broad categories or types of computer viruses:
1. Boot Sector Virus
2. File Infection Virus
3. Multipartite Virus
4. Network Virus
5. E-mail Virus
6. Macro Virus

Boot Sector Viruses

Viruses that aim at the boot sector of a hard drive are infecting a very crucial component of the boot process. The boot sector holds critical information that controls the hard drive and also the part of the operating program that is in charge of the whole boot process. These types of computer viruses go a long way toward the assurance they will be successful in their mission by absolutely loading into the system memory while the boot cycle is starting.

Unlike other viruses the boot virus does not affect files, instead it goes after the drive itself on which the virus is saved and this is part of the reason that it is no longer as big a threat as it used to be. Since the advent of cds and dvds and the drives that carry them it is not possible to infect the programs that they carry. In the days of floppy drives the virus could spread quite quickly from computer to computer via the disks but since it is not possible to infect a cd or dvd this virus has become almost a non threat. Another reason this types of computer viruses have become less common is that now operating systems stand guard over the boot sector and that makes it very hard for the virus to have any effect.

File Virus

File viruses are coded so that they will attach themselves to exe files, compressed files like zip files and driver files. The can be set into actions when the program they are attached to is started. Then after the virus is set into motion it will attach itself to other programs and system files and start along it's intended path for which it was written. So you see it is a two prong approach. First depending on the types of computer viruses it will duplicate and then go about its intended mission. The virus will search through the programs in the system and find places to infect with the code and then it will activate when that program is run next time. It will continue to duplicate until it is all over the computer and probably any computer that is attached to the original system.

Often these viruses will harbor special code that causes them to be activated when certain events take place. The event often is a date or some other trigger event that is easily defined on any computer system you may have.

Multipartite Viruses

That which has been termed the multipartite virus are the types of computer viruses that are both a file virus and a boot sector virus. They enter the computer via various sorts of media and then embed themselves in the system memory. They then go into the hard drive and infect the boot sector. Once installed in the boot sector these types of computer viruses infect executable files and spread themselves in the system.

This is another virus that has past its prime for various reasons but in times past these types of computer viruses were responsible for many infections because they combined characteristics of two different viruses into one.

Network Viruses

A virus that is especially made for networks is uniquely created to quickly spread throughout the local area network and generally across the internet as well. Most of the time is moves within shared resources like drives and folders. Once it finds entry into a system it will search for vulnerable computers in the network and likewise infect that system and do the same again and again always on the hunt for new vulnerable systems.

E-Mail Viruses

Most of the time a e-mail virus is one of those types of computer viruses that is generally a macro virus and it will multiply itself by seeking out the other contacts in a e-mail address book and then send itself to those addresses in hopes that they will activate the virus too. Thus it spreads over and over again exponentially. There are even times an email virus can spread by only previewing it in the mail client. One that was very successful in spreading worldwide was the ILOVEYOU virus and it was destructive too.

Macro Viruses

Macro viruses as the name implies, will infect files of programs that use macros in the program itself. The most common of these are the Microsoft Office files created in Excel spreadsheets, Word documents, Access databases, Powerpoint presentations and these type of files from AmiPro and Corel Draw and others.

One should always be on the lookout for these types of computer viruses and should take every precaution to avoid them. Be ever watchful of every file you open or else you may be looking for my next hub on how to remove these types of computer viruses.

RouterOS

MikroTik RouterOS is the operating system of MikroTik
RouterBOARD hardware.
It can also be installed on a PC and will turn it into a router
with all the necessary features - routing, firewall, bandwidth
management, wireless access point, backhaul link, hotspot
gateway, VPN server and more.
RouterOS is a stand-alone operating system based on
the Linux v2.6 kernel, and our goal here at MikroTik is
to provide all these features with a quick and simple
installation and an easy to use interface.
You can try RouterOS today, go to www.mikrotik.com and
download the installation CD image. The free trial provides
all of the features with no limitations.
In the following pages you will find examples of some of the
most important RouterOS features.