Anonymity
I can see you hiding in the shadows over there and so can the logs of all the web sites, FTP servers and other nooks and crannies you visit on the web. The sort of information gathered by these logs and which is available to the webmasters of the sites you visit include the address of the previous site you visited, your IP address, your computer's ID name, your physical location and the name of your ISP along with less personal details such as the operating system you're using and your screen resolution. If someone was snooping through your dustbin to gather information on consumer trends or tracking your every move to see where it is you go everyday you wouldn't be too chuffed would you. Well the web is no different, it's still an invasion of privacy and a threat to security and you don't have to put up with it.
Proxy servers:
Every time you visit a web site, detailed information about your system is automatically provided to the webmaster. This information can be used by hackers to exploit your computer or can be forwarded to the market research departments of consumer corporations who by tracking your activities on the internet are better equipped to direct more relevant spam at you. Your best defence against this is to use what is known as a proxy server, which will hide revealing information from the web sites you visit, allowing you to surf the web anonymously. These work by altering the way in which your browser retrieves web pages or connects to remote servers. With a proxy server set up, whenever you 'ask' IE or Netscape to look at a web page, the request is first sent through an external server which is completely independent of your ISP's servers. This third party server then does the requesting on your behalf so that it appears that the request came from them rather than you and your real IP address is never disclosed to the sites you visit. There is nothing to download and the whole process takes less than a minute.
There are two different ways to use proxy servers and both have their advantages and disadvantages. The first method is to use a web based service. What this involves is visiting the proxy's home page each time you want to browse a web site anonymously. The core component of such a system is the dialog box where you enter the address of the web site you want to visit. Each time you enter the URL of the site you want to browse via the proxy into this box, your personal information, IP address and so on is first encrypted before being sent to the site allowing you to maintain your anonymity. Two of the best examples of this type of web based proxy service are Code:
hxxp://www.rewebber.com/
and hxxp://www.anonymizer.com/.
Obviously one disadvantage of using a web based service like Rewebber or Anonymizer, however, is that you have to visit the proxies home page each time you want to surf anonymously. You could choose to select this page as your default home page, but it's still quite awkward if you're forever site hopping at the speed of light. The second main 'con' is that you often have to put up with extra adverts on the pages you visit. These are automatically inserted into the pages by the proxy - they have to pay for service somehow. More sophisticated and convenient solutions are also on offer yet they come with a price tag.
The second method you can use to protect your privacy via a proxy server involves adjusting the settings of your web browser so that you can surf anonymously without having to visit the home page of your proxy each time. To do this you will first need to know the name of your proxy server and the port number it uses. This information can be gleaned from either a public proxy server list or the FAQ referring to a private subscription based service. Once you have the name of the proxy server you wish to use, select 'Internet Options' from the 'Tools' menu of your browser. Now select 'Connections' followed by 'Settings' and tick the 'use a proxy server' check box. To finish the job all you have to do now is enter the name of the server in the 'address' box, the port which it uses in the 'port' box and go forth and surf anonymously.
Free, manual proxy servers as advertised on anonymity sites, if you can find one at all, are likely to be highly oversubscribed, and as a result the speed at which they retrieve web pages can deteriorate. In which case you can go in pursuit of a public proxy server list and select an alternative from it, which can then be set up manually. To locate such a list you can investigate sites such as Code:
hxxp://www.proxys4all.com/
however, this method isn't problem free either, so before you get too carried away and go jumping on the anonymity bandwagon there are a few things you should be aware of. It's very easy to use proxies to protect your privacy, but often the disadvantages of using them far out weigh the benefits. You see, the problem is that, like the proxy servers provided Rewebber et al, free, public proxies are nearly all over subscribed and so they can slow down web browsing considerably. Digging out fast reliable proxy servers is an art form in itself and is a skill which takes considerable practice. You could find a list of public proxy servers and then experiment with each one until you find one that runs at a reasonable speed, but this can be very time consuming and frustrating. Instead, your search would be much more efficient if you got a dedicated program to carry out this task for you. There are literally dozens of proxy seeking programs around which can do just that, and many of them are available as freeware. What these do is scan the internet for public proxy servers. These servers are then tested for speed and anonymity (not all of them are truly anonymous, even if they claim to be!) and once you find one which suits your requirements you can select it as your default proxy with the click of a button.
One of the most significant advantages of using an automated tool to locate proxy servers is that you do not have to keep editing your proxy settings manually each time you wish to try out a new one. Instead, what you do is enter 'localhost' or '127.0.0.1' into the 'address' box and '8088' into the 'port' box of your browser's proxy settings menu and then forget about it. All future proxy switching is then orchestrated from within your proxy seeking software, which subsequently relays the information to your browser or whatever type of application you are attempting to make anonymous. For those of you who are curious 'localhost' and the IP address '127.0.0.1' are the names by which every computer on the internet refers to itself.
Here's a good selection of links, which should help you to get started - Code:
hxxp://www.a4proxy.com/ Anonymity 4 Proxy
hxxp://www.helgasoft.com/hiproxy/ Hi Proxy
hxxp://www.proxy-verifier.com/ Proxy Verifier
hxxp://www.photono-software.de/ Stealther.
You may find that even when using these programs you have difficulty finding good proxy servers. It is for this reason that many people choose only to use proxy servers temporarily whilst doing something which may land them in trouble with their ISP, or in a worst case scenario with the law. The most obvious example of a situation in which you would want to cover your tracks is when scanning for public FTP servers and subsequently uploading to them. Most other net activities are unlikely to incur serious consequences so under these circumstances you can safely surf the web without a proxy. If you're really serious about protecting your privacy, however, your best bet is probably to invest in a dedicated, stable proxy such as the ones offered by Code:
hxxp://www.ultimate-anonymity.com/ Ultimate Anonymity
These aren't free, but may be worth the expense if you aren't keen on continuously switching proxy servers.
Before splashing out though it may be worth checking if your current ISP has a proxy server of its own which you can use. These aren't there to help you to commit cyber crimes and get away with it, they actually have a legitimate purpose as well - otherwise they wouldn't exist. You see, proxy servers were originally designed to help speed up web page loading times. Proxy servers contain a cache of all the web pages which have been requested via the browsers of the people using the proxy. When someone surfs the web using a proxy, the proxy first checks to see if it already has a copy of the web page stored in its cache. If this version of the page is bang up to date, it is sent to your computer and appears in your browser. If the page found in the cache of the proxy server is older than the one stored on the server hosting the page, a new request to the web server is made and the page is updated in the cache of the proxy before being sent to you. Because these servers use very fast internet connections they can retrieve web pages at much greater speeds than you can via your modest home setup. If these servers are located physically nearer to your home than the web host servers you wish to retrieve web pages from, the speed at which you browse the web will be accelerated.
Anonymity - Cookies
One last important point you need to be aware of before jumping in with both feet is that different programs have to be setup in different ways before being able to make external connections via a proxy server. For example, you can surf the web anonymously by modifying the settings in Internet Explorer or Netscape Navigator as explained earlier in this tutorial, but this will only affect your browser. If you then used Flash FXP to copy a batch of 0-day releases from one FTP server to another, this isn't going to protect you in the slightest. What you have to do is enter the name of the proxy server into each application you wish to make anonymous before making any external connections. This can usually be done by browsing through the preferences of your program to see if there is a 'use proxy server' option available. If there is, make sure you use it!
Cookies:
You have little to fear from the edible variety, but the digital ones can be a major threat to your security and privacy. A cookie is a tiny text file (usually less than 1kb in size), which is created and stored on your hard drive whenever you visit a dynamic (or an interactive if you like) web site. These are used to log your personal details so that you can access members only areas of web sites without having to type in a password every time, or to retain your customised settings so that they are available the next time you visit. If you're using a shared computer, anyone who visits the same site that you have previously logged in to can access your accounts. This is particularly worrying if you have entered your credit card details into a form on an e-commerce site. If your browser is set to automatically fill in these details whenever you
return to a previously visited site, this information could be clearly visible - you don't need me to explain the problems this could entail.
The solution to this problem is to delete any cookies which contain sensitive data once you have completed your transactions. Your cookies will be stored in a different place depending on which operating system you are using so you will have to use your detective skills to find them. As an example, in Windows XP they are located in your 'c:\Documents and Settings\Kylie Minogue\Cookies' directory (that is if your name is Kylie Minogue. Mine isn't in case you're wondering!). If you look in this directory, in some cases it is easy to identify which cookie is associated with which web site, but in other cases it's not so obvious. The cookie which was created when you visited Yahoo.com to check your email may be called kylie minogue@yahoo.txt for example. Unfortunately some cookies refer to the IP address of the site you visited and so look more like kylie minogue@145.147.25.21. These cookies can be selectively deleted one at a time if it's obvious which ones are causing a threat to your security, or you can just wipe out the whole lot in one fell swoop and have them recreated as and when they are required. However, if
you're really struggling to find your cookie jar, you could delete your cookies via your browser's tool bar instead. In Internet Explorer this can be done through the 'Tools' > 'Internet Options' menu items.
If all this sounds like too much hassle, you can always find a labour saving program which will be happy to take the job off your hands. These 'cookie crunching' programs allow you to be more selective when editing, viewing and deleting cookies from your system, and some of them will even prevent cookies from being created in the first place. Yes, I know you're hungry for links so I won't deprive you. Have a look here - Code:
hxxp://www.rbaworld.com/Programs/CookieCruncher/ Cookie
Cruncher
hxxp://www.thelimitsoft.com/ Cookie Crusher
hxxp://www.angove.com/ Cookie Killer
hxxp://www.kburra.com/ Cookie Pal
and
hxxp://www.cookiecentral.com/ Cookie Web Kit.
Wednesday, April 2, 2008
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Anonymity |
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10 reasons why PCs crash U must Know |
10 reasons why PCs crash U must Know
Fatal error: the system has become unstable or is busy," it says. "Enter to return to Windows or press Control-Alt-Delete to restart your computer. If you do this you will lose any unsaved information in all open applications."
You have just been struck by the Blue Screen of Death. Anyone who uses Mcft Windows will be familiar with this. What can you do? More importantly, how can you prevent it happening?
1 Hardware conflict
The number one reason why Windows crashes is hardware conflict. Each hardware device communicates to other devices through an interrupt request channel (IRQ). These are supposed to be unique for each device.
For example, a printer usually connects internally on IRQ 7. The keyboard usually uses IRQ 1 and the floppy disk drive IRQ 6. Each device will try to hog a single IRQ for itself.
If there are a lot of devices, or if they are not installed properly, two of them may end up sharing the same IRQ number. When the user tries to use both devices at the same time, a crash can happen. The way to check if your computer has a hardware conflict is through the following route:
* Start-Settings-Control Panel-System-Device Manager.
Often if a device has a problem a yellow '!' appears next to its description in the Device Manager. Highlight Computer (in the Device Manager) and press Properties to see the IRQ numbers used by your computer. If the IRQ number appears twice, two devices may be using it.
Sometimes a device might share an IRQ with something described as 'IRQ holder for PCI steering'. This can be ignored. The best way to fix this problem is to remove the problem device and reinstall it.
Sometimes you may have to find more recent drivers on the internet to make the device function properly. A good resource is www.driverguide.com. If the device is a soundcard, or a modem, it can often be fixed by moving it to a different slot on the motherboard (be careful about opening your computer, as you may void the warranty).
When working inside a computer you should switch it off, unplug the mains lead and touch an unpainted metal surface to discharge any static electricity.
To be fair to Mcft, the problem with IRQ numbers is not of its making. It is a legacy problem going back to the first PC designs using the IBM 8086 chip. Initially there were only eight IRQs. Today there are 16 IRQs in a PC. It is easy to run out of them. There are plans to increase the number of IRQs in future designs.
2 Bad Ram
Ram (random-access memory) problems might bring on the blue screen of death with a message saying Fatal Exception Error. A fatal error indicates a serious hardware problem. Sometimes it may mean a part is damaged and will need replacing.
But a fatal error caused by Ram might be caused by a mismatch of chips. For example, mixing 70-nanosecond (70ns) Ram with 60ns Ram will usually force the computer to run all the Ram at the slower speed. This will often crash the machine if the Ram is overworked.
One way around this problem is to enter the BIOS settings and increase the wait state of the Ram. This can make it more stable. Another way to troubleshoot a suspected Ram problem is to rearrange the Ram chips on the motherboard, or take some of them out. Then try to repeat the circumstances that caused the crash. When handling Ram try not to touch the gold connections, as they can be easily damaged.
Parity error messages also refer to Ram. Modern Ram chips are either parity (ECC) or non parity (non-ECC). It is best not to mix the two types, as this can be a cause of trouble.
EMM386 error messages refer to memory problems but may not be connected to bad Ram. This may be due to free memory problems often linked to old Dos-based programmes.
3 BIOS settings
Every motherboard is supplied with a range of chipset settings that are decided in the factory. A common way to access these settings is to press the F2 or delete button during the first few seconds of a boot-up.
Once inside the BIOS, great care should be taken. It is a good idea to write down on a piece of paper all the settings that appear on the screen. That way, if you change something and the computer becomes more unstable, you will know what settings to revert to.
A common BIOS error concerns the CAS latency. This refers to the Ram. Older EDO (extended data out) Ram has a CAS latency of 3. Newer SDRam has a CAS latency of 2. Setting the wrong figure can cause the Ram to lock up and freeze the computer's display.
Mcft Windows is better at allocating IRQ numbers than any BIOS. If possible set the IRQ numbers to Auto in the BIOS. This will allow Windows to allocate the IRQ numbers (make sure the BIOS setting for Plug and Play OS is switched to 'yes' to allow Windows to do this.).
4 Hard disk drives
After a few weeks, the information on a hard disk drive starts to become piecemeal or fragmented. It is a good idea to defragment the hard disk every week or so, to prevent the disk from causing a screen freeze. Go to
* Start-Programs-Accessories-System Tools-Disk Defragmenter
This will start the procedure. You will be unable to write data to the hard drive (to save it) while the disk is defragmenting, so it is a good idea to schedule the procedure for a period of inactivity using the Task Scheduler.
The Task Scheduler should be one of the small icons on the bottom right of the Windows opening page (the desktop).
Some lockups and screen freezes caused by hard disk problems can be solved by reducing the read-ahead optimisation. This can be adjusted by going to
* Start-Settings-Control Panel-System Icon-Performance-File System-Hard Disk.
Hard disks will slow down and crash if they are too full. Do some housekeeping on your hard drive every few months and free some space on it. Open the Windows folder on the C drive and find the Temporary Internet Files folder. Deleting the contents (not the folder) can free a lot of space.
Empty the Recycle Bin every week to free more space. Hard disk drives should be scanned every week for errors or bad sectors. Go to
* Start-Programs-Accessories-System Tools-ScanDisk
Otherwise assign the Task Scheduler to perform this operation at night when the computer is not in use.
5 Fatal OE exceptions and VXD errors
Fatal OE exception errors and VXD errors are often caused by video card problems.
These can often be resolved easily by reducing the resolution of the video display. Go to
* Start-Settings-Control Panel-Display-Settings
Here you should slide the screen area bar to the left. Take a look at the colour settings on the left of that window. For most desktops, high colour 16-bit depth is adequate.
If the screen freezes or you experience system lockups it might be due to the video card. Make sure it does not have a hardware conflict. Go to
* Start-Settings-Control Panel-System-Device Manager
Here, select the + beside Display Adapter. A line of text describing your video card should appear. Select it (make it blue) and press properties. Then select Resources and select each line in the window. Look for a message that says No Conflicts.
If you have video card hardware conflict, you will see it here. Be careful at this point and make a note of everything you do in case you make things worse.
The way to resolve a hardware conflict is to uncheck the Use Automatic Settings box and hit the Change Settings button. You are searching for a setting that will display a No Conflicts message.
Another useful way to resolve video problems is to go to
* Start-Settings-Control Panel-System-Performance-Graphics
Here you should move the Hardware Acceleration slider to the left. As ever, the most common cause of problems relating to graphics cards is old or faulty drivers (a driver is a small piece of software used by a computer to communicate with a device).
Look up your video card's manufacturer on the internet and search for the most recent drivers for it.
6 Viruses
Often the first sign of a virus infection is instability. Some viruses erase the boot sector of a hard drive, making it impossible to start. This is why it is a good idea to create a Windows start-up disk. Go to
* Start-Settings-Control Panel-Add/Remove Programs
Here, look for the Start Up Disk tab. Virus protection requires constant vigilance.
A virus scanner requires a list of virus signatures in order to be able to identify viruses. These signatures are stored in a DAT file. DAT files should be updated weekly from the website of your antivirus software manufacturer.
An excellent antivirus programme is McAfee VirusScan by Network Associates ( www.nai.com). Another is Norton AntiVirus 2000, made by Symantec ( www.symantec.com).
7 Printers
The action of sending a document to print creates a bigger file, often called a postscript file.
Printers have only a small amount of memory, called a buffer. This can be easily overloaded. Printing a document also uses a considerable amount of CPU power. This will also slow down the computer's performance.
If the printer is trying to print unusual characters, these might not be recognised, and can crash the computer. Sometimes printers will not recover from a crash because of confusion in the buffer. A good way to clear the buffer is to unplug the printer for ten seconds. Booting up from a powerless state, also called a cold boot, will restore the printer's default settings and you may be able to carry on.
8 Software
A common cause of computer crash is faulty or badly-installed software. Often the problem can be cured by uninstalling the software and then reinstalling it. Use Norton Uninstall or Uninstall Shield to remove an application from your system properly. This will also remove references to the programme in the System Registry and leaves the way clear for a completely fresh copy.
The System Registry can be corrupted by old references to obsolete software that you thought was uninstalled. Use Reg Cleaner by Jouni Vuorio to clean up the System Registry and remove obsolete entries. It works on Windows 95, Windows 98, Windows 98 SE (Second Edition), Windows Millennium Edition (ME), NT4 and Windows 2000.
Read the instructions and use it carefully so you don't do permanent damage to the Registry. If the Registry is damaged you will have to reinstall your operating system. Reg Cleaner can be obtained from www.jv16.org
Often a Windows problem can be resolved by entering Safe Mode. This can be done during start-up. When you see the message "Starting Windows" press F4. This should take you into Safe Mode.
Safe Mode loads a minimum of drivers. It allows you to find and fix problems that prevent Windows from loading properly.
Sometimes installing Windows is difficult because of unsuitable BIOS settings. If you keep getting SUWIN error messages (Windows setup) during the Windows installation, then try entering the BIOS and disabling the CPU internal cache. Try to disable the Level 2 (L2) cache if that doesn't work.
Remember to restore all the BIOS settings back to their former settings following installation.
9 Overheating
Central processing units (CPUs) are usually equipped with fans to keep them cool. If the fan fails or if the CPU gets old it may start to overheat and generate a particular kind of error called a kernel error. This is a common problem in chips that have been overclocked to operate at higher speeds than they are supposed to.
One remedy is to get a bigger better fan and install it on top of the CPU. Specialist cooling fans/heatsinks are available from www.computernerd.com or www.coolit.com
CPU problems can often be fixed by disabling the CPU internal cache in the BIOS. This will make the machine run more slowly, but it should also be more stable.
10 Power supply problems
With all the new construction going on around the country the steady supply of electricity has become disrupted. A power surge or spike can crash a computer as easily as a power cut.
If this has become a nuisance for you then consider buying a uninterrupted power supply (UPS). This will give you a clean power supply when there is electricity, and it will give you a few minutes to perform a controlled shutdown in case of a power cut.
It is a good investment if your data are critical, because a power cut will cause any unsaved data to be lost.