Run Linux in Windows

Many users of Windows XP and Vista will want to try Linux at some point, often just to see what all the fuss is about. There are many different Linux distributions and it isn’t convenient for a non-technical user to set up dual booting alongside an existing Windows install. Thankfully, there are tools available which mean you can play with a full Linux install inside the familiar surroundings of Microsoft Windows.

There are several pieces of software that let you run a virtual PC within Windows, allowing you to install virtually any operating system in an emulated PC environment. There are two main solutions available, firstly the free Microsoft Virtual PC 2007, which is reasonably good and easy to install. The second choice is also a free piece of software and is called VMware Player, and features several more advanced features. For this article we will be using the MS Virtual PC virtualisation software as it provides more flexibility in the free version.

Step 1 - Install the Microsoft Virtual PC Software

This is a very straight forward installation, and the download is around 30-60MB (depending on components) at the time of this article:

http://www.microsoft.com/windows/products/winfamily/virtualpc/overview.mspx

Step 2 – Locate and download a Linux Distribution

Once Virtual PC is installed, you need to download a Linux distribution. Some popular choices are:

Ubuntu : http://www.ubuntu.com/
Fedora : http://fedoraproject.org/
Mandriva : http://www.mandriva.com/

Proceed to the download section of whichever distribution you choose, and if you are given plenty of options of types to download then look for a 32bit i386 ISO file.

This article will use Ubunutu, and the download URL at the time was:

http://mirror.ox.ac.uk/sites/releases.ubuntu.com/releases/hardy/ubuntu-8.04-desktop-i386.iso

Once you have found the file, download it to your PC.

Step 3 – Setup a Virtual PC

Load MS Virtual PC 2007 from the start menu and begin the wizard to create a new virtual machine, the screenshots below illustrate this process using recommended settings. Click Next to begin the setup process:

Select “Create a new virtual machine”:

Call this virtual machine whatever you like, for example “Linux” or “Ubuntu”:

Select “Other” from the OS dropdown menu to customise the virtual PC:

Choose how much system RAM you wish to allocate to the virtual PC, if you can spare it, 512MB would be recommended. It does appear to allocate the whole amount of memory to the software, even if you are only using a small portion of it within the Virtual PC. 512MB should be fine for users with 2GB+ of Ram, but those with 1GB may struggle to run much else in the background.

Select create “A new virtual hard disk”:

Choose a location to save this virtual drive and assign a size (dependant on how much disk space you have left). You can make up to 3 virtual hard drives, but if you wanted more drives you can always partition them to as many drive letters as required.

Click finish to create the Virtual PC:

Step 4 – Install Linux

Select the Virtual PC listed under the name assigned during setup, and then click start:

This will start to boot up the Virtual PC, although there is no operating system installed at present. To install Linux, click CD > Capture ISO Image and then open the saved Linux ISO from Step 2. If you find that your mouse pointer is stuck within the Virtual PC window, press right-ALT to release it:

Once this is done, click Action > Reset to reboot the Virtual PC and start the Linux Install. During boot, the Linux install will automatically load and the onscreen installation steps must be followed. These steps will differ slightly for each Linux distribution, but it should be a straight forward process. If you use Ubuntu, select the “Install Ubuntu” option rather than running the Live CD:

This will start the graphical installer where you can customise your install options. This article will not cover each installation step, as it will vary for each install. However, in most cases it is just a case of filling in basic information and clicking “next” as there is only 1 possible installation drive. Unless you are an advanced user, allow Linux to automatically partition your virtual drive:

Once the installation is complete the Virtual PC will restart, at which point you should unmount the ISO file by clicking CD > Release CD. Once the restart is complete, you should now be at the Linux login screen:

Congratulations, you now have a working Linux install from within Windows! To boot in to Linux again simply load Virtual PC 2007 from the start menu and double click on the Linux name (as in the first stage of Step 4).

Author: Ian Cunningham
Published on: 29-06-2008

Hard Drive Data Recovery

One of the most important points for any computer user to remember is to always back up your data. As much as personal computing has advanced over the past 20 years, hard drives still fail. Hard Drives are an amazing piece of mechanical engineering, as then spin (sometimes continuously) at around 120 times per second (7200 rpm). These spinning platters are spinning at such high speeds that a small interference whilst in usage can damage the disk in a certain area. There are now fail safe mechanisms in place to prevent critical failures when there is a small amount of physical damage done to the drive, but accidents do happen.

When some areas of the disk fail, the hard drive is effectively useless. Cases like this usually require specialists to come and recover any data that might be left. If you have made routine backups of your important data, this would be a great inconvenience to restore and install all the applications and data once more, but still recoverable. If you were unfortunate enough not have any backups (or not recent ones), then you are in trouble. Data Recovery is a very time consuming process, and often quite expensive. Fortunately, there are some data recovery procedures that you can try before having to resort to professionals.

Sometimes a hard drive can be partitioned in to several drives that appear on the computer, and in some cases a single partition from several partitions can fail on one physical drive. This means that all is most likely not lost, and it will probably be recoverable with a little work. Many people simply give up and purchase a new drive, loosing all data, when they could easily recover the data first.

If your hard drive makes ill-sounding mechanical failure noises (loud clicking, rattling, scratching), then back up your data as fast as possible and buy a new hard drive. If you fail to recover the data when the drive is on the brink of no return, you will often have to pay for a specialist data recovery company to recover the data from the physically damaged drive.

Understanding

Understanding how Hard Drives store data

You can check the status of your partitions and file systems by running the Computer Management application that comes with Windows XP (Right click 'My Computer', then 'Manage', then 'Disk Management'). The example below shows a single 30GB drive which has one primary FAT32 partition.

Every hard drive runs a type of File System, a method by which the operating system installed can organise data and free space in a way that it can be written to and read from. Each physical disk can be split up into many partitions, each partition can in turn appear as a logical drive (addressed C:, D:, E: etc...). This guide will only deal with the 2 primary partition types used for Windows Operating Systems - FAT16/32 and NTFS.

NTFS (NT File System) is now the most common File System, and it is used by Windows NT/XP. FAT-32 is used by Windows 98 and upwards, where as FAT-16 was used by DOS/3.1/95. The most recent operating systems are backwards compatible with older file systems, and can read/write to secondary disks based on the older file system.

Both file systems organise the way the data is stored by using a Master Boot Record (MBR) and a Partition Table. These are found in the first sector of the drive, and determine how the disk structure is organised and instructs the computer which partition to boot from.

Author: Ian Cunningham

Spyware and Adware Removal

Spyware and Adware are two of the major annoyances for many computer users, slowing down PCs and obtaining information - all done covertly. Most computers connected to the internet will in fact be infected with some form of spyware, with users being blissfully unaware (apart from maybe a few strange occurrences whilst browsing). There are some forms of adware that will actually cost user dearly, which will be covered later on in the article.

Companies and individuals that create spyware applications often make huge sums of money, and yet claim to offer a valuable "free service" to innocent surfers. Spyware and Adware are essentially applications which can be bundled with "free" software or are installed in a sneaky manor, that serve to make someone a lot of money without the user knowing.

Most of these applications will run silently on a PC, causing a variety of nasty effects:

• Adding affiliate links to many large stores, causing the software creator to earn around 5-15% commission for almost every item you purchase online.
• Adds extra advertising on webpages, or even replaces existing advertising.
• Monitoring browsing habits for commercial purposes.
• Gain access to passwords and credit card numbers
• Slow PCs down by using up system resources.
• In some cases, they can dial premium rate numbers to earn the company money.
• Changing homepages and extra bookmarks
• Strange icons and new software on the desktop

As you can see, there are plenty of problems caused by spyware and adware, and could even end up costing dearly in sever circumstances. Most users will suffer from slow computers, laden with extra adverting and lack of privacy. Although, credit card details and passwords could be obtained in some circumstances.

Luckily, there are plenty of free software applications that will remove these troublesome leeches. There is no "one size fits all" solution to the growing adware / spyware problem, but the following guide will give you a comprehensive tutorial to securing your system from this comon problem.

How it got there?

How did the spyware/adware get installed originally?

Spyware and Adware are obviously never advertised as such, and have many modes of infection. The most common modes are (but not confined to):

ActiveX Installation:

Windows has a very useful tool for installing applications over the internet, called ActiveX. This allows developers to create applications that can run from within a webpage. Many sites including Windows Update and Shockwave use this tool to install the necessary files on the users computer.

Many pornography, illegal or questionable sites often have pop-up windows claiming to install some "free" component, often suggesting that it is the only way to view the site. These ActiveX applications can often contain dialer programs, which dial premium rate numbers and mount up phone bill costs.

It is true that these dialog boxes must have the "yes" clicked to install the ActiveX program, but there are many sneaky ways to get the user to click this button accidentally. The dialog box always contains the text "Do you wish to install and run".... followed by the product title. Spyware/Adware is sneaky and makes the title of their application suit the flow of text by changing it to something like "Do you wish to install and run a free application that will let you download the latest MP3s and Ringtones?". Many users will fall for this "great, free application"... if only they knew!

Luckily, Windows XP SP2 includes a feature that will not allow an ActiveX control to be installed with the user being 100% sure of it. A bar will pop-up in the Internet Explorer browser window, which must be accepted before the Installation box will even pop up. Many other browsers contain similar features now. If you do not have SP2 installed, visit the Windows Update site now to download it.

Piggybacking:

As the name suggests, the spyware/adware can act as a parasite and hide itself in other supposedly free software. Software such as "gator" or "bonsai buddy" is simply a method of concealing spyware which monitors your browsing habits and adds extra advertising to your PC. Many P2P applications come with these applications as part of the install package, as do some other freeware software packages. These companies will be paid a small amount of money for each person that subsequently has the spyware installed on their PC.

Always be careful when using any software that could install a few nasty surprises when using it. These applications are also able to download and install another other software they want once running.

Security Flaws / Viruses :

Although this method of transfer is far less than the other methods, it is the most dangerous of all. Even with SP2 and all of the latest updates, there are plenty of ways to run a file on a remote computer, all without the knowledge of the user. Viruses are one way to spread spyware/adware, but security holes in software can also run some spyware installers.

Author: Ian Cunningham
Published on: 27-09-2004

Better Browsing With Service Pack 2

Before Service Pack 2, Internet Explorer posed one of the biggest security risks in Windows XP. Critical update patches were frequently being released to fix it, but internet Explorer simply had too many security holes. Now Service Pack 2 (SP2) brings a new level of security to internet Explorer, as well as dealing with those irritating pop-up windows and advertisments. In this step-by-step guide you'll learn about Internet Explorer’s new security features, the Pop-up blocker, the all-important Add-on Manager and updated file-download feature.

Pop-up windows are undeniably annoying. SP2 improves Internet Explorer (IE) to such an extent that the chance of you becoming frustrated by the appearance of unwanted windows is all but eliminated. In this example I’ve directed my web browser to a special web site designed to test the effectiveness of pop-up-blocking applications. You can try it out for yourself at Pop-up Tester

It may not be immediately obvious, but the yellow banner at the top of IE’s window is a new feature provided by SP2. Called the Information Bar, it alerts you to warnings regarding the likes of pop-ups, activex controls and file downloads. As you’ll see from visiting popuptest.com, the Information Bar has appeared stating that a pop-up was blocked. Note also that the information about a particular notification "Pop-up blocked. To see this pop-up or additional options click here…"

If you click on the Information Bar, you’ll be presented with a list of options relating to the action that IE has taken. The first option is to temporarily allow the pop-up, and is rather useful, as some sites, such as the BBC, which uses pop-up windows to present extra information. By selecting this, all pop-ups will be permitted on this page, but when you try to reload it again they will be blocked. If you suspect that previously blocked pop-ups may contain something of interest, this option allows you to confirm quickly.

The second option, as you might have already guessed, allows you to tell IE to always allow a particular website to display pop-ups. This means that the site’s address will be added to a “safe list” and IE’s pop-up blocker will be deactivated every time you visit that site. I’ll talk about how to manage your ‘safe list’ in a moment.

To alter the pop-up settings, click on the Tools menu in IE and select Internet Options. Now click on the Privacy tab and look at the bottom of the dialogue box, where you’ll notice the Pop-up Blocker section. You can completely disable the blocker here by clicking once to remove the tick from the Block pop-ups checkbox.

With the Internet Options dialogue box still displayed, click on the Settings button. This launches the Pop-up Blocker Settings window, which you’ll see is split into two sections. The first section is titled Exceptions and allows you to create a list of sites that are permitted to display pop-ups. To add a site, type the web address into the appropriate entry box and click on the Add button. As you do, the website’s address will appear in the allowed sites area below.

The second section lets you alter what happens when a pop-up is blocked and what filter level to select. There are three filter levels to choose from, ‘High’ will block all pop-ups, ‘Medium’ will block most, while the ‘Low’ setting will allow pop-ups from all secure internet sites, such as banking or shopping pages. If you hold down the Crtl button on your computer’s keyboard while loading a website, IE will temporarily suspend its pop-up-blocking facility.

The Add-On Manager is another major feature that SP2 brings to IE. It gives you greater control over add-ons and allows you to disable them if you suspect some are causing problems with the running of IE. To open the Add-on Manager, open the Tools menu and select Manage Add-ons option.

The Add-on Manager has a basic-looking interface. When you first open it you’ll see a list of add-ons that are currently being used by IE. If you’re experiencing problems in IE, it’s worth checking out whether any of the currently loaded ad-ons are to blame. Click on the drop-down list next to the Show label and you’ll see that you can view add-ons that are not only currently being used, but those that have been used in the past. This gives you a complete overview of all add-ons that are available to IE.

It’s a simple task to disable any individual add-on. All you have to do is highlight the add-on in question and, from the Settings section in the bottom-left corner of the window, click on the Disable option. However, as a warning message that appears explains, you will need to restart IE for the changes to take effect, so click on OK and do just that. If you are having problems in IE, try disabling add-ons on a trial and error basis.

Some of the add-ons listed might be ActiveX controls. These provide extra features that are not available as standard in the HTML code that is the common language of the web. Many AxtiveX controls are frequently updated. If you want to check for updates, select an ActiveX control in the list and hit the Update ActiveX button. You may have to wait while your PC downloads the updated control.

Internet Explorer’s File-Downloading system has also been given a revamp with the release of SP2. Whenever a website attempts to download a file to your computer, the Information Bar will appear to inform you that a download is about to take place. If you’re tiring of the regular interruptions by the Information Bar’s pop-up box, place a tick in the “Do not show this message again” checkbox and click OK.

Click on the Information Bar and you’ll be presented with three options. Rather obviously, choosing "Download File…" will indicate your acceptance of the download. The second option, "What’s the Risk?" will present an explanation of the potential harm posed by any given file type, while the final option provides help on the Information Bar itself.

If you accept the download, you’ll be presented with a new-style download dialogue box. The usual options of being able to run the file directly after download or save it to the hard drive are still available, but a new warning level, based on the nature of the download, will also appear. IE warns that files with an .EXE extension can harm a PC, and so advises caution.

Author: muckshifter
Published on: 10-10-2004

What is a Firewall..?

A personal firewall is a software application which filters traffic entering or leaving your computer. When you're connected to the Internet, information is flowing to and from your PC in a near-constant stream through your PC's "ports". There are thousands of "ports" and they are like little gates that let information in and out.

Some of the information moving through the ports is obvious to you. For example, when you :

• Send and receive emails
• Access a website
• Fill in and submit a form on a website
• Download software like MailWasher Pro or Benign

However, a lot of information flows to and from your PC without you knowing about it. This can include:

• Your copy of Windows talking to the Microsoft website to check for security updates
• Software applications talking to their own companies' websites to check for new versions
• Anti-virus software checking for the latest virus updates.

Most of this invisible information flow is good. However, some of it poses a grave threat to your PC and your privacy.

Your email isn't the only way bad things can get into your computer. They can come in through your PC's open ports without you even knowing about them. The "Blaster" worm of August 2003 was the most widespread example of this. In case you don't remember, that was the one that caused your PC to shut down about a minute after you'd started it up!

If you leave your PC's ports open and don't monitor them, you're at extreme risk of the following nasties:

VIRUSES: Programs or pieces of code that "infect" one or more of the programs on your PC. Basically, your programs "get sick" and start performing in weird ways, which sometimes can lead to a system crash.

WORMS: Malicious programs that propagate over a network, reproducing as they go. Worms cause the same effects as viruses but they are more dangerous since they spread by themselves.

PORT SCANNING: Hackers scan the open ports on your PC to figure out if they are open or exist at all. If your computer reports an open port, a hacker can send a worm and virus to it. They can even use an open port to take control of your PC.

COOKIES: Small data files placed on your PC by a website that you've visited. A cookie can store your personal information after you enter it online. For example, if you type in your log-in details, a cookie might store it till you come back next time. This is not a bad idea - most shopping sites use cookies completely legitimately so you don't need to keep entering your personal details. But problems can occur when other people decide to use your personal details too!

TROJANS: Programs that appear legitimate but do something illicit when run. Just like the wooden horse the Greeks gave Troy as a "gift", users mistake the Trojan for a useful or interesting program that they choose to download. Once installed and run, Trojans can secretly open remote access channels to hackers, relay passwords and credit card data or destroy user files. It's similar to a virus but generally does not replicate itself.

DENIAL OF SERVICE (DOS) ATTACKS: This kind of attack happens when a hacker finds a responding port on your PC and sends a huge amount of data to it. The port is just unable to accept all of the data, the system resources exhaust, and the system crashes and denies service.

SPYWARE: These are programs secretly placed on your PC that gather information about you (such as your surfing habits, what other software you have on your PC, etc.) without your knowledge or consent. Spyware is mostly used by on-line or software companies for marketing purposes.

So how does a firewall help to stop all of these bad things from happening?

As mentioned at the start, a firewall controls communications to and from your PC. It permits or denies communications based on a Security Policy.

According to the security policy you set for it, a firewall can ...

• Make your PC invisible on the Internet. Your ports don't just appear closed; they don't even appear at all. This is very good!
• Automatically block suspicious incoming traffic.
• Alert you every time a program on your PC tries to send information to another computer. This stops spyware and Trojans from sending hackers your confidential information, such as credit card details and passwords.
• Do a lot more things too, but these are the most basic and important functions it carries out.

So in short, if you don't have a firewall installed, then as soon as you connect to the Web (before you even start your browser or e-mail client) you are open to attack - because some or all of your ports are open and unmonitored. A firewall is especially important if you have a high-speed Internet connection. Hackers love to take over broadband machines because then they can use them to spread spam even faster!

Now you're probably wondering where to get one of these firewalls, aren't you? There are plenty of good firewalls around, some free and many paid. Zone Alarm has a free and more extensive paid version.

Author: muckshifter
Published on: 12-09-2004

Computer Network Installation

Computer network installation has become an essential prerequisite for any efficient modern-day business as it allows employees to truly work as a team by sharing information, accessing the same database and staying in touch constantly. For a computer network to give the best results, a lot of detailed planning and foresight is required before installation. Firstly, an organisation needs to clearly define its requirements – how many people would use the network, how many would use it locally (within the office) and how many might require remote access (from a different location), how many computers and other devices (servers, printers, scanners) would be connected to the network, what are the needs of the various departments and who would be in charge of running/managing the network. It also helps if one can anticipate the direction the company would take in the near future so potential growth can be factored in during computer network installation. The technology issues should also be ironed out in advance – hardware, software, servers, switches, back-up devices, cables and network operating systems. Make sure you have the required licenses to run the software on all your machines before installing a computer network. Alongside computer network installation should proceed the building of a dedicated technical support staff, either within your own organisation or outside consultants. Delegate responsibility clearly for network management. Before installing the network, you also need to choose the security mechanism to protect corporate data and keep viruses at bay. The transition to a new or upgraded computer network can bring some teething problems. To minimise chances of confusion, the company might need to train its staff to make them familiar with the new system. Careful planning will to a large extent prevent crises like system downtime and network crashes. If you are planning to install a computer network or upgrade and existing one, contact Viper System at sales@vipersystems.co.uk for help. About Author :Adrian Griffiths

Computer Network Designing

Computer network designing takes into account different aspects and topics. An ideal computer network design will be based on the layout, capacity planning, and security plans.
Computer network design requires a good understanding of the topologies such as a bus, ring, star, so on. Designing a network has to follow certain rules. The set of rules governing the setup of a network is called its topology. Ethernet, today, is the most popular topology in use. It consists of computers and peripherals cabled together in specific ways. Ethernet is relatively cheaper, easy to set up and use, and faster. There are two types of Ethernet – Standard and Fast Ethernet.
To talk of the cables, you can use the twisted-pair (also known as 10BaseT) or the thin coax (also known as 10Base2) for your network cable. The choice, however, will depend on the type of network you’re setting. You can use both the types together. Twisted pair cabling is cheaper, flexible, and ideal for cabling short distances. You can use thin coax for larger networks.
A network interface card (NIC) connects the network computer to the network cabling. While some NICs are installed inside the computer others may need PCI slots. A network adapter is needed when the network is supposed to support very high speed data transfer.
The final piece you need to get through the network design is a hub. It is used to gather groups of PCs together at a central location. The type of your network and data transfer support required will again decide the type of hub the network requires.
Understanding the roles of these bits of hardware and the nature of network to be built takes you a long way in deigning the ideal computer network.
Understanding the implementation of network protocol and services design also contributes to a good computer network design. You can use other area networks besides LANs and WANs. A good knowledge about the different forms of area networks and their roles in network designing throws up better ideas for the framework.
However, the two significant elements influencing network designing are the bandwidth and latency supported by a network.
Bandwidth in computer networking means the rate at which data can travel through a network connection or interface. It is usually expressed in bytes per second (bps). Bandwidth, however, is just one element that dictates the speed of a network. Latency, the other important element of speed refers to the delays in processing different types of network data. Usually, tools such as ping and trace-route assess latency by determining the time taken by a network packet to travel from source to destination and back.
Once you have planned the budget and the various factors influencing a network design, you can think about the various template designs. You can think of a symmetric computer network, where all devices can transmit and receive data at equal rates, or an asymmetric one which can supports different proportion of data or bandwidth in different direction.
About Author :Adrian Griffiths, write article and provide consultancy to Viper Systems