Most motherboards now come with sound, video, and even networking built-in. But a modem is not usually built-in to a motherboard. This is because modem technology has been changing very rapidly. It is preferable to have the modem on an expansion card.
Most modem manuals assume that Plug and Play will automatically install the modem correctly, but this is rarely the case. Use the four steps described below to properly install a modem.
Step 1. Download the latest driver from the manufacturer's Web site.
Most modems come with an Installation CD. The problem with this is that the CD contains drivers for eight different operating systems and it usually tries to install the wrong one. Even if it does install the correct driver, its usually not the latest version. Also, the CD usually comes with several non-essential programs (AOL etc.) that the modem company earns commission on when you install them.
I admit, its difficult to download a driver before you install the modem. You may be replacing an old modem, or you may have another computer, or a friend with a computer with access to the Web.
Preferably, do this before you purchase the new modem. That way you can see what kind of driver and technical support is available for the modem before you shell out the cash.
Step 2. If you are replacing a modem, remove the old modem. First physically open the case and remove the old modem. Then start the computer and remove the modem in Control Panel. If the system is Windows 2000 you will have to login as Administrator. Open the Modems utility, select the name of the modem on the General tab. Then click on the Remove button.
Step 3. Install the new modem.
First physically install the new modem. If the system is Windows 2000 you will have to login as Administrator. Plug and Play may install the new modem for you, that means it found an old driver on your system and used that to install the modem. Or it may start the "Add New Hardware Wizard". Click on the Cancel button.
The "Add New Hardware Wizard" is rarely able to find the proper driver for a modem, and when the Wizard appears as the computer starts, it blocks your access to Explorer, so you can't use Explorer to locate a driver. Just click on the Cancel button to close the Wizard.
After Windows starts you can open the "Add New Hardware Wizard". The Wizard will attempt to detect any new hardware. Then it will give you the option to “select the hardware from a list." Choose the option to select from a list, then click the Next button. In the list select "modem" and click on the Next button. Then it will give you the option to let windows "try to detect your modem" or "select the modem from a list."
PnP will not be able to detect your modem if it's a model developed after your Windows installation disc was mastered. Nor will it appear on the list. Just select the closest match from the list, then update the driver
afterwards.
If Plug and Play installs old drivers, open the Control Panel "System" utility. Click on the Device Manager tab and in the device type list, open the branch for "Modem". Select the name of the modem and click on the "properties" button. The modems "Properties" dialog box will open. Select the "Driver" tab and click on the "Update Driver..." button. The "Update Driver Wizard" appears. Use the Wizard to install the new modem driver.
Don't be surprised if the "Update Driver Wizard" updates the driver by removing the modem and adding it again (with the new driver).
The modem "driver" will most likely not be a single file. It might be a group of files with extensions like .vxd, .exe, .ini, .dll, etc. The list of files is contained in a text file with the extension .inf. So when you install the "driver" you are actually reading the files and other configuration from the .inf file.
Step 4. Don't forget to reconfigure your dial-up connection with the new modem. If you are a system
administrator, don't forget to see that everyone else's dial-up connection gets updated as well.
Using the four steps described above, you can work around Plug and Play to properly install a modem with the latest drivers.
Permission is granted for the below article to forward, reprint, distribute, use for ezine, newsletter, website, offer as free bonus or part of a product for sale as long as no changes are made and the byline, copyright, and the resource box below is included.
How to Really Install a Modem
System Restore: The Big Undo
System Restore is the ultimate band-aid fix for buggy Microsoft Windows. If you make a hardware or software change to your Windows Me or Windows XP system, and then it doesn't work right, System Restore acts like a giant "undo".
For System Restore to work, you need a "restore point" to go back to. A restore point saves a copy of the registry, drivers, and crucial operating system files. The files are saved as compressed .cab files in a folder named _RESTORE/ARCHIVE.
System Restore monitors all partitions on your computer (Windows XP lets you select which drives to monitor) and automatically creates restore points. The actual number of restore points saved depends on how much disk space has been allocated for System Restore. System Restore will not run if your system has less than 200 MB of free space.
= Types of Restore Points
- System Check Points: Scheduled restore points created by Windows. System Restore automatically creates a restore point every 10 hours (if your computer is on). Your computer must be idle for a few minutes before a restore point can be created.
- Manual Restore Points: Just before you make a hardware or software change to your system, you can maually create a restore point.
- Installation Restore Points: Restore points created by an installation program. Not all installation programs create a restore point.
= Make sure System Restore is enabled
1. Select Start Settings Control Panel and open System Utility.
2. On the Performance tab, click on the [File System] button. The "File System Properties" dialog box appears.
3. In the File System Properties" dialog box select the "Troubleshooting" tab.
4. On the "Troubleshooting" tab, make sure the "Disable System Restore" checkbox is not checked.
= To Create a Restore Point
1. Select Start Programs Accessories System Tools System Restore. The "Wecome to System Restore" window will appear.
2. In the "Welcome to System Restore" window, set the "Create Restore Point" radio button. Then click in the [Next] button. The "Create Restore Point" window will appear.
2. In the "Create Restore Point" window, enter a name for your restore point. For example, "Before Modem Upgrade". Then click on the [Next] button.
3. After a period of disk activity, the "Confirm New Restore Point" window will appear displaying the date and name of your restore point. Click on the [OK] button.
= Restoring Your System
You made a hardware or software change to your system, and now it doesn't work right. If Windows won't start, press the F8 key while your computer is starting. The "Startup Menu" should appear. In the Startup Menu select "Safe Mode". In safe mode, or if Windows does start, select
Start Programs Accessories System Tools System Restore
The "Welcome to System Restore" window will appear. Click on the [Next] button. On the "Choose a Restore Point" page, click on a restore point to highlight it. If there are no restore points listed, click on the [back arrow] button on the calendar until you find the most recent restore point. Then click on the [Next] button. System Restore restores your system to the state it was in at the restore point you selected
and then restarts your computer.
= Note: System Restore does not undo any changes that you made to files you created with your applications. If a restore doesn't work, you can undo it, and select a different restore point.
When Microsoft created this big band-aid fix called System Restore, they admitted that Windows is an unstable operating system. Now we should be able to get compensated for all the productivity we lost because of Windows crashing.
Learn How To Install A Sound Card Fast
Sound Card installation is indeed simple and rather straight forward,that is,when you know how to do it. Opening the system unit can be a scary task for some of us,especially if we have not performed this task before.
The key is to be calm,take your time,and make it fun. Look forward to looking inside the computer and see just how many components you can readily identify. PC Repair's cdrom one and the PC Test cdrom are filled with photos and video clips of these components. Remember to touch a doorknob or any grounded metal object to remove static electricity from your body.To install your new sound card,let's perform the following.
OPEN THE SYSTEM UNIT
Remove the system unit cover and locate an empty expansion bay.Note that the rear cover of the slot may have to be removed on most computers.Before touching anything,ground yourself to remove any buildup of elecrtical static charge from yourself. Touching the computer case or a boorknob will do the job.
With the cover removed from the system unit,lay the computer on its side.You may have to remove other connections or devices to have clear access to the empty card bay.
Take notes of any devices or connections that you make so that you can refer to them during installation of the new card.
New sound cards must be installed in the PCI slot. After removing the small rear cover,remove the new card from its protective wrap.This wrap is intended to keep the card away from electrical static charge.
INSTALLING THE SOUND CARD
Grasp the card and align it with the PCI slot. Slowly but firmly press the new card completely in the PCI slot.Check to be sure no part of the yellow
contacts can be seen when the card is pushed in. Secure the sound card to the system unit by using the screw that you removed when removing the rear cover.Use this screw to secure the card to the case. If you have on sound installed on the motherboard and you want to install another card,most systems will disable the motherboard integrated sound.If not, consult your computer manual to find the correct jumpers to disable the motherboard sound.
Now the cdrom audio cable must be connected. Insert one end of the audio cable for the cdrom or dvd drive into the CD-IN socket of the sound card. The other end is inserted into the audio-out socket of the cdrom or dvd drive.
Check and double check all connections before you replace the system unit cover.If all connections are good,replace the cover and reboot the system after all peripherals are reconnected.
REPLACE THE SYSTEM UNIT COVER
The computer should automatically detect the new card and attempt to install the device drivers needed to communicate with the card.Windows should prompt you to install the software needed to allow the card to communicate to the computer. The new card should have come with a cdrom with device drivers and other software for the card.Simply inserted the cdrom in the cdrom drive and select the cdrom installation when prompted.
Test the new sound card by re-booting the computer. You should hear the Windows startup sound if the card is operational.In some cases,the new card will be operational without rebooting your computer.
Installing or upgrading your sound card
is that easy.
Introduction to Dedicated Servers
A dedicated server is a single computer on a web-hosting network that is leased or rented, and dedicated to just one customer. A service provider monitors the computer’s hardware, network connectivity, and routing equipment, while the customer generally controls and maintains the server software. Dedicated servers are most often used by those who’ve outgrown typical hosting accounts and now require massive amounts of data space and bandwidth, those with mission critical web sites, web hosting companies, or those who have special needs. Dedicated servers are housed in data centers, where service providers can monitor them close-up and have hands-on access to them.
The primary advantage of using a dedicated server over a typical shared hosting account is the sheer amount of resources and control available to you, the customer. In many cases, the client is at liberty to install whatever software they desire, giving them greater flexibility and administrative options. Dedicated server clients do not share resources, as those with shared hosting plans do; but rather, are at liberty to use all the resources available to them.
Managed Servers vs. Unmanaged Servers
There are two types of dedicated servers available today: Managed Dedicated Servers and Unmanaged Dedicated Servers.
An Unmanaged Dedicated Server leaves nearly all the management duties of running a server in the purchaser’s control. The customer in this case, updates software on their own, applies necessary patches, performs kernel compiles and operating system restores, installs software, and monitors security. With this type of dedicated server, the consumer is solely responsible for day-to-day operations and maintenance. The service provider, in turn, monitors the network, repairs hardware problems, and troubleshoots connectivity issues. Additionally, some service providers offer partial management of services, such as network monitoring, software upgrades and other services, but leave the general upkeep of the server in the hands of the client. An unmanaged dedicated server is best for someone with server management experience.
A Managed Dedicated Server is generally more proactively monitored and maintained on the part of the service provider. When renting or leasing a managed server, the service provider or host carries out the responsibility of software updates and patches, putting security measures in place, performing hardware replacements, and also monitoring the network and its connection for trouble. In other words, when utilizing a managed dedicated server, the host provider will perform both hardware and software operations. A managed dedication server solution works well for the customer with limited server management experience or limited time in being able to perform the duties necessary to keep a server running and online.
Technical Aspects In Choosing A Server
When choosing a dedicated server, there are several things to consider: Operating System, Hardware options, Space and bandwidth.
The Operating System of a server is similar to that on your own personal computer; once installed, the operating system enables one to perform tasks more simply. There are a bevy of server operating systems available today including Linux-based and Windows-based software. The operating system you choose should be directly relational to what operations your server will be performing, which types of software you’ll need to install and also, what you’re more comfortable with.
Hardware Options are also something to consider when choosing a dedicated server. You’ll need to pick a
processor that’s up to the task, the amount of memory you wish installed, firewall options, and the size of the hard drive.
A certain amount of bandwidth is generally included when renting or leasing a dedicated server. Once you ascertained how much bandwidth you will require, you can adjust that limit with your service provider. The space you’ll be given is generally directly relational to the size of your hard drive. Some hosts also give clients the choice of uplink port speed (usually 10Mbps/100Mbps).
Protect Your PC from Viruses, Worms & Trojans
Each of the items in the checklist below is part of a broad and easy to implement security policy.
If you create a similar program, you can protect yourself and your PC from the numerous threats to your security and privacy.
1. Install all windows security patches for your operating system from the Microsoft Update site - it's free! All that's required to keep your operating system up to date is an Internet connection.
2. Install and configure a firewall - either a hardware or software based firewall is a must! If you are using a router, it probably has firewall capabilities included. Software firewalls are available at minimal cost; one of the best is free!
3. Install and configure antivirus software - the cost is minimal, there are even free versions available - the protection is priceless! Update it daily - scan your drives weekly - it can all be automated with most programs.
4. Create a backup - even the best plan can be circumvented - be prepared for the worst with a complete backup of your hard drive! If you already have a CD burner and software installed in your machine, you probably have
the tools to create a complete system backup - for only the cost of a few CD-R's!
Obviously, the costs to properly protect yourself from the worst threats to your security are almost nil. If you need help with any step above, simply use a Google search to find help - it's freely available.
Follow these four simple steps and you will have implemented comprehensive and complete protection for your PC. If you are unable to initiate your own plan, hire an expert to do the job. You won't be sorry!
-----------------
Mike Burstein has been helping the SOHO and Small Business community grow & prosper for over 20 years by solving start up problems, creating best practices, automating their offices, getting free publicity and dramatically increasing traffic and sales. http://www.sohowiz.com/
Caring for a Laptop
If you take a bit of care, you should never have to worry about returning the laptop in anything but pristine condition.
The Top 10 of Basic Computer Maintenance
1. Backup, backup backup! Backing up your data just means saving your files to a separate location (like a cd, floppy or zip disk) so in event of disaster you can easily copy your files back onto your computer. How often really depends on you. Just ask yourself, "If I only back up once every 3 months, would anything I saved on my hard drive since the last time I saved it on a backup be allright if I could NEVER get it back?" 2. Invest in an UPS (uninterruptible power source). A UPS is a wonderful device that works as a surge protector and a battery backup all in one! Not only does it keep your computer safe from electrical spikes that can be traveling through the lines, it also gives you time to save your work, and properly power down your computer in event of a power failure. You don't lose your work, and your computer gets to be shut down properly. 3. Never turn the computer off with the power switch. The one exception to this rule is when your computer locks up and your hard drive is not running (the hard drive light is not blinking). In this situation, you can turn the power off without harmful effects to the hard drive. As cutting the power can also result in lost data or Windows files, you should only do this when you have to. Doing this can help prevent permanent hard drive damage caused by the hard drive heads contacting the surface of the drive disc. This can prevent a host of Windows problems. Whenever possible, recover from crashes by pressing the Ctrl + Alt + Delete keys at the same time and going into your Task Manager. You can often find programs that are not responding in here, and chose to close them from this utility. Press Clt + Alt + Delete again to reboot your computer from this screen. 4. Scan disk and defrag once a month. These utilities help to keep your hard drive in optimal shape and error free. 5. Do not unplug peripheral devices while the power is turned on. Unplugging devices such as your mouse, keyboard, printer etc with the power on can short out the connector socket or even the motherboard itself. The only time you would unplug something while the power is on, is if the device is hot swappable/pluggable. If you are unsure if something is hot swappable or not, power down first to play it safe. 6. Remove programs from your startup. Often when you install a program, it will ask you whether it should load up as soon as Windows loads (or just decide to do so on its own). The more programs you have trying to start up at the same time, the slower your computer will start. Also, all those programs running in the background while you try to work will slow your computer's response time. In windows 98, ME, and XP, you can do this by going to your Start -> Run -> in the command box type in 'msconfig' and a small window will appear. Go to the tab marked "Startup" and you can chose what items to remove from there. In Windows 2000, you can do this by going to your Control Panel -> Administrative Services -> Services. 7. Run virus checks and adware/spyware scans regularly (at least once a week). There are so many types and variations of viruses, spyware and adware floating around that at times it may seem daunting to even have internet access on your computer. However, regular scans with your virus scanner, and adware scanners, can ensure your computer remains healthy. 8. Keep disks handy. If the worst thing happens, and you need to format your system for one reason or another, then it is a good idea to have all your driver disks, operating system disks, backup disks and so forth in a readily available place. Running around in a panic at the 11th hour because you cannot remember where the drivers are for your network card, is not a good place to be. 9. Keep your software updated. Software developers are always writing and releasing patches that update the software you have already bought from them. A lot of these patches fix problems you may be experiencing yourself with a particular program. Other patches plug security leaks. Still other patches update reference files for your virus/spy/adware scanners to make sure you are scanning for as many variants as possible. So make sure you regularly update/patch your operating system, virus scanners, and various other applications! 10. Develop a schedule of maintenance practices. All this advice is meaningless if you keep forgetting to do it, or only remember after something has gone wrong. Write yourself up a maintenance schedule, with a list of what tasks should be performed daily, weekly, and monthly. If you develop a routine and stick to it, then you should avoid the larger problems by always being on top of the smaller ones!
Keeping Old Computers Alive
There are many reasons to replace your computers before they could reasonably be called old. Big corporations may replace their computers every three years or less. I usually recommend that nonprofits replace their computers every four years. One reason to do this is so computers are replaced before they fail, so that down-time can be scheduled instead of being caused by unexpected failure. Productivity increases with newer computers, as people spend less time waiting for programs to open and respond to commands.
Newer computers have newer technology, which means improved security, stability, and new features. Or maybe there is a new software package you want to use -- and your old computer doesn't meet the system requirements.
But there are good reasons to keep old computers around. Maybe you just don't have the money to buy a new one. Or you may be in a part of the world where replacement computers are not only expensive -- they're hard to come by. Or maybe you want to wait as long as possible before sending the lead, mercury, and other toxic materials in your computer into the environment, and using more resources to build a new computer that you may not yet need.
For any of these reasons, you might want to keep your old computer running well, even if it is four, five, or six years old.
(If you're interested in keeping older Macs running, read "Resources for Older Computers" on TechSoup.)
Extending the Usable Life of a Computer
As computers get older, different things can go wrong. You may experience problems with the software, the operating system may respond sluggishly, or you may receive error messages. Maybe you can't open a program, or it crashes unexpectedly. You may also run into hardware problems: the CD-ROM drive won't open, your floppy drive won't reliably read disks, or your modem just stops working.
To extend the life span of a computer, consider what can go wrong, how to prevent and recover from those problems, and how to change the way you use your computer:
- What Can Go Wrong with Software?
- Preventing Problems with Software
- What Can Go Wrong with Hardware?
- Preventing Mechanical Hardware Problems
- Preventing Electrical Hardware Problems
- Upgrading Hardware
- Changing Hardware Roles
- Changing Operating Systems
- Changing Paradigms
What Can Go Wrong with Software?
Problem: Too Much Software
The biggest software problem on old computers is that there is too much of it. When a computer has been in an office for a long time, it tends to accumulate software like the junk drawer in your kitchen. Having too much software can cause a variety of problems.
Unnecessary software can take up too much room on the hard drive. If the hard drive is completely full or nearly full, the operating system won't run well. On a newer computer, having lots of software is less of a problem because new hard drives tend to be big. But on an old computer with a small hard drive, your system may respond sluggishly.
In addition, as programs are added to a computer, they may take up more of its memory. Some programs, particularly little ones downloaded from the Internet, stay active in your system's RAM even when you're not using them in order to open more quickly when you do want to use them. In Windows, these "memory resident" applications can often be seen in the system tray in the lower right-hand corner of the screen. In Mac OS 9, you might have extensions taking up memory that really aren't needed. On a newer computer with RAM to spare, lots of memory resident applications may not be a big deal. But on an old computer with little RAM, you should free up as much memory as possible.Solution: Remove Unnecessary Software
First, decide what software is necessary. Consider the difference between "need" and "want." Be ruthless. You may want iTunes so you can listen to streaming audio while you work, but do you need it? Old computers can't afford such luxuries; only keep what you really need to do your work.
In Windows, go to the Add/Remove Programs control panel. Determine for certain which software applications you don't need. If you're not sure, make certain that you have the original installation disks so you can reinstall if necessary. Then uninstall the software you don't need.
If software you do need shows up in the system tray, you may be able to disable its tendency to always stay open. For example, in Microsoft Windows you may see the icon for MSN Messenger in your system tray. In the options for the program you can set it not to launch automatically when the computer starts up. This will free up some memory for other purposes.
In Mac OS 9, open the Extensions Manager and disable extensions you don't need. If you don't know what you need and what you don't, consult with an expert.
Problem: New Software, Old Hardware
It's a sad fact, but you can't install just any software on any computer. For example, let's say you have a Pentium II with 128 MB of RAM running Windows 2000. If you use the right software, you won't have problems with this set-up. But if you install the latest version of Photoshop, it just won't work. I frequently find older computers with installed with software that just won't work well -- such as Mac OS X on an original bondi blue iMac. Even if you can install it, that doesn't mean it will run well.
Solution: Stay Within Your Limits
Before installing any new software, check the system requirements. Make sure that it is not more than your computer can handle. Make sure you have enough room on the hard drive and that it is compatible with the operating system you're running. If the software needs more than you're able to provide in terms of system resources, don't install it.
But what if you need to add software to your older computer? For example, let's say you want to add Microsoft Access to a computer in order to open a database. When you go to TechSoup Stock, you find that your nonprofit is eligible to order a donated copy of Microsoft Office Professional, which includes Microsoft Access. But wait -- they only offer Office 2003, which has high system requirements. What to do? You could upgrade your hardware to meet the system requirements (more on that later), or you could pick an earlier version of the software -- say, Office XP.
"But Office XP isn't available through TechSoup Stock!" you wail. I'll let you in on a little secret. When you obtain a software license for Microsoft products through TechSoup Stock, that license entitles you to use older versions of the software. I know this is a little confusing; the point is, eligible organizations can obtain older versions of Microsoft products through TechSoup Stock. (Read more about the process on TechSoup Stock -- although the instructions refer to Windows XP, it works for other Microsoft software, too.) If you're not eligible to order donated software through TechSoup Stock, you may be able to order discounted software from an Open Charity License reseller -- this principle applies to these licenses, too. You can buy Office 2003 and install Office XP.
This act of buying new software but installing older software is sometimes called "downgrading." The rules vary from vendor to vendor, so do some research before assuming you can downgrade.
Problem: Spyware
This is mostly a problem with Windows. Spyware, adware, and other junk software on your computer is always undesirable, regardless of the age of your computer. But again, on an old computer every bit of memory is precious. You cannot allow these invasive programs to steal your valuable system resources.Solution: Spyware Removal Tool
Use a spyware removal tool such as Spybot Search and Destroy or Ad Aware. A nice feature of Spybot is that it can "innoculate" your computer against future infections. Best of all, it's free. Read more about removing malware on TechSoup.
Problem: Viruses
As with spyware, this problem mostly affects Windows users. (There just aren't that many viruses for the Mac OS.) Viruses are a problem with computers new and old, but they are more likely to turn up on old computers. This is simply because an old computer has been around longer, so it has a greater chance of being infected with a virus. There's also a greater chance users have lapsed on upgrading anti-virus software.
Solution: Anti-Virus Software
If you're going to run an old computer, you have to keep it clean if you expect it to perform. That means having up-to-date anti-virus software.
Preventing Problems with Software
Performing regular maintenance will forestall problems with your operating system and other software. That means installing updates from the software vendor, defragmenting the hard drive, running Scandisk on Windows 98 or chkdsk on Windows 2000 or Windows XP. Be prudent about installing only what you need to do your work. Don't install software just for fun. Ultimately, you'll be a lot happier if your computer is running well.
What Can Go Wrong with Hardware?
There's basically only one thing that goes wrong with hardware: it breaks. If it's not broken, the problem isn't with the hardware. By "broken," I mean worn out, bent, burned up, cracked, smashed, or otherwise inoperable.
So what can break? Just about anything in your computer can break, but the parts that move are more likely to break:
- ventilation fans
- the fan in the power supply
- the fan on the processor
- the hard drive
- the CD-ROM drive
- the floppy drive
- moving parts in the printer
- moving parts on the mouse
If something appears to be broken, first determine whether it's actually broken. I won't go into detail here on troubleshooting hardware, but suffice to say that cracking open the mouse and cleaning the dust bunnies out of the rollers can make a "broken" mouse work like new.
Preventing Mechanical Hardware Problems
You can help keep moving parts running by using them gently and removing sources of friction. The biggest source of friction is dust, including hair and cigarette ashes.
Keeping your work area clean will prolong the life of your computer. Dust your desk regularly. Vaccuum the floor to reduce the amount of dirt there. Don't smoke in your office: you already know it's not good for you or your coworkers, and now you know it's not good for your computer. Once a year or so, open your computer's case and blow out any dust with a can of compressed air.
Preventing Electrical Hardware Problems
Power surges can break electronics. Test your electrical outlets to see if they are properly grounded, and use a good-quality surge protector to protect your equipment from voltage spikes. Dusting out computers also helps lower their temperature, which improves performance and prolongs the life of electrical components.
Upgrading Hardware
- RAM: To see the biggest increase in performance, increase the amount of RAM in an older computer. Put in as much as the computer will support. You can find what kind of RAM you need and how much your computer will support by looking at the documentation for the computer on the manufacturer's Web site. If you have a generic computer or can't find the information, consult with a expert to figure out what you need and where you can find it. Don't assume that just because it fits you can drop a 256MB RAM DIMM in your computer. Make sure that the computer supports the size and the type of the RAM you are installing.
- Video card: Replacing the video card with a newer one that has more memory can also improve performance. If your older computer has an AGP slot, replacing a PCI or onboard video adapter with an AGP video card can speed up the computer.
- Hard drive: An old hard drive is probably a slow hard drive. Replacing the hard drive in your old computer with a new one will give your machine an added boost. In an older machine with a slow (66 MHz) IDE controller, you should consider adding a PCI IDE 133 expansion card to match a new IDE 133 hard drive. Keep in mind that replacing the hard drive probably means reinstalling the operating system and all your programs, so don't plan on taking this step unless your time (or the environment) is more important to you than your money.
- Processor: It's usually more trouble than it's worth to replace the processor or the motherboard.
If you're upgrading on a budget, you may be able to get used parts for free or for cheap from a computer recycling organization.
Changing Hardware Roles
If a computer is too old to be servicable as a desktop computer for one purpose, you may yet find a use for it.
- Appropriate assignment: Does your receptionist need to do work with graphics or PowerPoint? Give him your newest computer. Does your intern really only answer e-mail and surf the Web on the computer? An older computer might fit the bill. When a computer is suited to the task at hand, its age doesn't matter as much.
- File or print server: An older computer can often make a perfectly adequate file or print server. Windows 98 also doesn't have the same 10-user limit that Windows 2000 imposes.
- Firewall or router: You could also put an old computer into service as a firewall or router using Coyote Linux. All you need is any old computer with a working motherboard, two network cards, and a floppy drive. No CD-ROM or hard drive are required.
Changing Operating Systems
One of the best ways to bring new life to an old PC is to erase it and start over with some version of Linux. Some Linux distributions such as Cobind are specifically intended for use on older hardware. Cobind Linux has many features of a modern operating system. Like all versions of Linux, it is unbelievably stable and highly secure. Cobind will run well on a Pentium II 300MHz processor with 64MB of RAM and a 2GB hard drive.
Changing Paradigms
Old computers can make excellent terminals in a thin-client network. In your standard small office environment, programs are run on separate computers: I might run an e-mail program on my computer, while you run a database on your computer. In a thin-client network, all programs are run on one computer, which is connected to many terminals so that multiple users can access that one computer system at once. So instead of replacing old computers with new ones, an organization could use a single higher powered machine as a terminal server, and use the old PCs as terminals. A terminal in a set-up like this doesn't need a hard drive, much of a processor, or memory. It doesn't do any processing at all -- it just provides a window onto the terminal server.
Depending on the applications that staff need to run, an organization could use the same old Pentium II PCs for years. The only reason to finally remove them from service would be hardware failure.
Basic Computer Maintenance
Basic Computer Maintenance
Keeping Software Up-to-date on Public Access Computers
These tips have been adopted from Aaron Schmidt’s “Smart Computing at Your Library” presentation at the Internet Librarian 2005 conference in Monterey, California on October 24. You can view Aaron’s original presentation at his web site.
These tips apply to public access computers (PAC) running any version of the Microsoft Windows operating system. The goal of these tips is to help you keep those PACs up-to-date with the latest critical software releases.
You should also note that any public access or shared computer security system, such as Centurion Guard, Deep Freeze, Fortres 101, or the Microsoft Shared Computer Toolkit, will probably need to be disabled or bypassed to perform these updates. How this will need to be done will depend on the particular security system. It could mean logging in as an administrator, unlocking via a password, or even using a physical key.
In some cases these tips recommend alternative software packages that differ from the default applications found on most Windows PACs. The following substitutions are specifically recommended:
· Use Mozilla Firefox as the default web browser in place of Internet Explorer.
· Replace the default version of RealPlayer with the spyware-free “BBC version.”
· Replace the Microsoft Virtual Machine (VM) with the Java Runtime Environment (JRE).
Beyond the obvious implications for computer security, keeping software applications up-to-date can prevent annoying update messages appearing while patrons are using the PACs. In most cases, patrons will not have the correct operating system permissions to take action on prompted updates, so if library staff take the time to perform these update tasks periodically, it will help to ensure “smooth sailing” for your PAC users.
Many of the resources in the last column of the table below lead to web pages from which you can download updated software versions. It’s a good idea to check what version of a particular product you are currently using before visiting the relevant download page – if you already have the latest version installed, there’s no need to download a new version. You can determine the version of any installed program by opening the program, and going to the Help / About (product name) menu option.
In general, it is recommended that you have library staff perform these tasks outside regular business hours, when the PACs are not in use by patrons. Performing these tasks regularly on a weekly, bi-weekly or monthly basis will keep help keep your PACs fully functional and (hopefully) trouble-free.
Multiple Programs
You can run two programs on the same line in Windows XP's Command Prompt window. To run two programs, you type in their names separated by an ampersand (&). For example, you'd type:
Program1 & Program2
and press Enter. In this example, Program2 starts as soon as Program1 finishes executing.
Put It on the Desktop
You can get to Windows Explorer much more easily if you put it on the desktop.
To place a shortcut to Windows Explorer on your desktop, run Windows Explorer and navigate to \Windows. Locate Explorer.exe and use the right mouse button to drag its icon to the desktop. When you release the mouse button, choose Create Shortcut(s) Here. Now you just double-click your new shortcut to open Windows Explorer.
Make it Wide Always
If you'd like to have your directory listings show up in wide format, try this. You need to change the DIRCMD. Click Start, Settings, Control Panel, and double-click the System icon. When the System Properties dialog box opens, click the Advanced tab. Next click the Environment Variables button. Then click the New button in the User Variables area. In the Vairable Name field, type
dircmd and press Tab to move to the Value entry box. In Value, type /w and click OK. Finally, click OK to close the dialog box and apply your new settings. From this point on, typing DIR at the Command Prompt produces the wide listing.
Custom Internet Shortcuts
You can create your own custom shortcuts to Internet sites using Notepad. Just run Notepad and enter the following as shown here.
[InternetShortcut]
URL=http://www.yoursite.com
Choose File--Save As and then click the arrow at the right side of the "Save as Type" list box and select All Files.Name your file Yoursite.url and select a folder for it. Click Save to save the file. Note that you can name a file whatever you wish, but you must use the URL extension.
Block Pop-up with Internet Explorer
Block Pop-up Windows with Internet Explorer
Many legitimate advertisers on the Internet use windows that pop up in the middle of your screen to display a message. They might also open when you click a link or button on a Web site, and they might open either over or under the window you wish to view. Some pop-ups are helpful. For example, if you click an image to see a larger version, it might open in a pop-up window. Unfortunately, some pop-up windows can contain inappropriate content or can be a way for you to accidentally download dangerous software (called spyware or adware) onto your computer.
With Windows XP Service Pack 2 (SP2) Internet Explorer allows you to prevent most pop-up windows from appearing over pages you want to view while you're using the Internet.
Using Pop-up Blocker
When you install SP2, Pop-up Blocker is turned on in Internet Explorer and set to the medium setting, which means it will block most automatic pop-ups. The default settings for the pop-up blocker allow you to see pop-ups that are opened when you click a link or button on a Web site. Pop-up Blocker will also play a sound and show the Information Bar when a pop-up is blocked. You can adjust these settings so that Pop-up Blocker works the way you want it to.
To change Pop-up Blocker settings
1. | Open Internet Explorer. |
2. | On the Tools menu, point to Pop-up Blocker, and then click Pop-up Blocker Settings. |
If you want to see pop-up windows from a specific Web site, type the address (or URL) of the site in the Address of Web site to allow box, and then click Add.
Tip To temporarily allow a site to display pop-ups, click the Information Bar when it notifies you that a pop-up has been blocked. Then click Temporarily Allow Pop-ups.
To block pop-ups even if they are launched when you click a link or button on a Web site
1. | Open Internet Explorer. |
2. | On the Tools menu, point to Pop-up Blocker, and then click Pop-up Blocker Settings. |
3. | Select the High setting in the box near the bottom of the dialog box. |
Note If you want to see pop-ups that are blocked when you have this setting turned on, hold down the CTRL key while the window opens.
Troubleshooting Pop-Up Blocker
If you've installed SP2 and you still see pop-ups in Internet Explorer, try the possible solutions below.
| • | Make sure Pop-up Blocker is turned on: Pop-up Blocker is turned on by default, but someone may have turned it off. |
To turn on Pop-up Blocker
1. | On the Tools menu, point to Pop-up Blocker. |
2. | Click Turn on Pop-up Blocker. |
| • | Rid your system of spyware: If you get similar pop-up windows no matter what sites you visit or even if you're not on the Web at all, you could have spyware, adware, or other software on your computer that's launching pop-ups. To stop these pop-ups, you will have to identify the software, then remove it or change its settings to stop it from launching pop-ups. To learn more about this read How to Protect Your Computer from Spyware and Adware. |
| • | Some windows are not blocked: Pop-up Blocker is smart enough to not block pop-up windows that you open deliberately by clicking a link—for example, if you were on a travel reservation site and you clicked a link to open a pop-up window containing your confirmation details, this pop-up window would not be blocked because you opened it intentionally. Also, Pop-up Blocker will not block some pop-ups with certain types of animated content or pop-ups from Web sites that are in two Web content zones: Local intranet or Trusted sites. To learn more about security zones, see Working with Internet Explorer 6 Security Settings. |
Introduction to TCP/IP
Introduction to TCP/IP
Summary: TCP and IP were developed by a Department of Defense (DOD) research project to connect a number different networks designed by different vendors into a network of networks (the "Internet"). It was initially successful because it delivered a few basic services that everyone needs (file transfer, electronic mail, remote logon) across a very large number of client and server systems. Several computers in a small department can use TCP/IP (along with other protocols) on a single LAN. The IP component provides routing from the department to the enterprise network, then to regional networks, and finally to the global Internet. On the battlefield a communications network will sustain damage, so the DOD designed TCP/IP to be robust and automatically recover from any node or phone line failure. This design allows the construction of very large networks with less central management. However, because of the automatic recovery, network problems can go undiagnosed and uncorrected for long periods of time.
As with all other communications protocol, TCP/IP is composed of layers:
- IP - is responsible for moving packet of data from node to node. IP forwards each packet based on a four byte destination address (the IP number). The Internet authorities assign ranges of numbers to different organizations. The organizations assign groups of their numbers to departments. IP operates on gateway machines that move data from department to organization to region and then around the world.
- TCP - is responsible for verifying the correct delivery of data from client to server. Data can be lost in the intermediate network. TCP adds support to detect errors or lost data and to trigger retransmission until the data is correctly and completely received.
- Sockets - is a name given to the package of subroutines that provide access to TCP/IP on most systems.
Network of Lowest Bidders
The Army puts out a bid on a computer and DEC wins the bid. The Air Force puts out a bid and IBM wins. The Navy bid is won by Unisys. Then the President decides to invade Grenada and the armed forces discover that their computers cannot talk to each other. The DOD must build a "network" out of systems each of which, by law, was delivered by the lowest bidder on a single contract.
The Internet Protocol was developed to create a Network of Networks (the "Internet"). Individual machines are first connected to a LAN (Ethernet or Token Ring). TCP/IP shares the LAN with other uses (a Novell file server, Windows for Workgroups peer systems). One device provides the TCP/IP connection between the LAN and the rest of the world.
To insure that all types of systems from all vendors can communicate, TCP/IP is absolutely standardized on the LAN. However, larger networks based on long distances and phone lines are more volatile. In the US, many large corporations would wish to reuse large internal networks based on IBM's SNA. In Europe, the national phone companies traditionally standardize on X.25. However, the sudden explosion of high speed microprocessors, fiber optics, and digital phone systems has created a burst of new options: ISDN, frame relay, FDDI, Asynchronous Transfer Mode (ATM). New technologies arise and become obsolete within a few years. With cable TV and phone companies competing to build the National Information Superhighway, no single standard can govern citywide, nationwide, or worldwide communications.
The original design of TCP/IP as a Network of Networks fits nicely within the current technological uncertainty. TCP/IP data can be sent across a LAN, or it can be carried within an internal corporate SNA network, or it can piggyback on the cable TV service. Furthermore, machines connected to any of these networks can communicate to any other network through gateways supplied by the network vendor.
Addresses
Each technology has its own convention for transmitting messages between two machines within the same network. On a LAN, messages are sent between machines by supplying the six byte unique identifier (the "MAC" address). In an SNA network, every machine has Logical Units with their own network address. DECNET, Appletalk, and Novell IPX all have a scheme for assigning numbers to each local network and to each workstation attached to the network.
On top of these local or vendor specific network addresses, TCP/IP assigns a unique number to every workstation in the world. This "IP number" is a four byte value that, by convention, is expressed by converting each byte into a decimal number (0 to 255) and separating the bytes with a period. For example, the PC Lube and Tune server is 130.132.59.234.
An organization begins by sending electronic mail to Hostmaster@INTERNIC.NET requesting assignment of a network number. It is still possible for almost anyone to get assignment of a number for a small "Class C" network in which the first three bytes identify the network and the last byte identifies the individual computer. The author followed this procedure and was assigned the numbers 192.35.91.* for a network of computers at his house. Larger organizations can get a "Class B" network where the first two bytes identify the network and the last two bytes identify each of up to 64 thousand individual workstations. Yale's Class B network is 130.132, so all computers with IP address 130.132.*.* are connected through Yale.
The organization then connects to the Internet through one of a dozen regional or specialized network suppliers. The network vendor is given the subscriber network number and adds it to the routing configuration in its own machines and those of the other major network suppliers.
There is no mathematical formula that translates the numbers 192.35.91 or 130.132 into "Yale University" or "New Haven, CT." The machines that manage large regional networks or the central Internet routers managed by the National Science Foundation can only locate these networks by looking each network number up in a table. There are potentially thousands of Class B networks, and millions of Class C networks, but computer memory costs are low, so the tables are reasonable. Customers that connect to the Internet, even customers as large as IBM, do not need to maintain any information on other networks. They send all external data to the regional carrier to which they subscribe, and the regional carrier maintains the tables and does the appropriate routing.
New Haven is in a border state, split 50-50 between the Yankees and the Red Sox. In this spirit, Yale recently switched its connection from the Middle Atlantic regional network to the New England carrier. When the switch occurred, tables in the other regional areas and in the national spine had to be updated, so that traffic for 130.132 was routed through Boston instead of New Jersey. The large network carriers handle the paperwork and can perform such a switch given sufficient notice. During a conversion period, the university was connected to both networks so that messages could arrive through either path.
Subnets
Although the individual subscribers do not need to tabulate network numbers or provide explicit routing, it is convenient for most Class B networks to be internally managed as a much smaller and simpler version of the larger network organizations. It is common to subdivide the two bytes available for internal assignment into a one byte department number and a one byte workstation ID.
The enterprise network is built using commercially available TCP/IP router boxes. Each router has small tables with 255 entries to translate the one byte department number into selection of a destination Ethernet connected to one of the routers. Messages to the PC Lube and Tune server (130.132.59.234) are sent through the national and New England regional networks based on the 130.132 part of the number. Arriving at Yale, the 59 department ID selects an Ethernet connector in the C& IS building. The 234 selects a particular workstation on that LAN. The Yale network must be updated as new Ethernets and departments are added, but it is not effected by changes outside the university or the movement of machines within the department.
A Uncertain Path
Every time a message arrives at an IP router, it makes an individual decision about where to send it next. There is concept of a session with a preselected path for all traffic. Consider a company with facilities in New York, Los Angeles, Chicago and Atlanta. It could build a network from four phone lines forming a loop (NY to Chicago to LA to Atlanta to NY). A message arriving at the NY router could go to LA via either Chicago or Atlanta. The reply could come back the other way.
How does the router make a decision between routes? There is no correct answer. Traffic could be routed by the "clockwise" algorithm (go NY to Atlanta, LA to Chicago). The routers could alternate, sending one message to Atlanta and the next to Chicago. More sophisticated routing measures traffic patterns and sends data through the least busy link.
If one phone line in this network breaks down, traffic can still reach its destination through a roundabout path. After losing the NY to Chicago line, data can be sent NY to Atlanta to LA to Chicago. This provides continued service though with degraded performance. This kind of recovery is the primary design feature of IP. The loss of the line is immediately detected by the routers in NY and Chicago, but somehow this information must be sent to the other nodes. Otherwise, LA could continue to send NY messages through Chicago, where they arrive at a "dead end." Each network adopts some Router Protocol which periodically updates the routing tables throughout the network with information about changes in route status.
If the size of the network grows, then the complexity of the routing updates will increase as will the cost of transmitting them. Building a single network that covers the entire US would be unreasonably complicated. Fortunately, the Internet is designed as a Network of Networks. This means that loops and redundancy are built into each regional carrier. The regional network handles its own problems and reroutes messages internally. Its Router Protocol updates the tables in its own routers, but no routing updates need to propagate from a regional carrier to the NSF spine or to the other regions (unless, of course, a subscriber switches permanently from one region to another).
Undiagnosed Problems
IBM designs its SNA networks to be centrally managed. If any error occurs, it is reported to the network authorities. By design, any error is a problem that should be corrected or repaired. IP networks, however, were designed to be robust. In battlefield conditions, the loss of a node or line is a normal circumstance. Casualties can be sorted out later on, but the network must stay up. So IP networks are robust. They automatically (and silently) reconfigure themselves when something goes wrong. If there is enough redundancy built into the system, then communication is maintained.
In 1975 when SNA was designed, such redundancy would be prohibitively expensive, or it might have been argued that only the Defense Department could afford it. Today, however, simple routers cost no more than a PC. However, the TCP/IP design that, "Errors are normal and can be largely ignored," produces problems of its own.
Data traffic is frequently organized around "hubs," much like airline traffic. One could imagine an IP router in Atlanta routing messages for smaller cities throughout the Southeast. The problem is that data arrives without a reservation. Airline companies experience the problem around major events, like the Super Bowl. Just before the game, everyone wants to fly into the city. After the game, everyone wants to fly out. Imbalance occurs on the network when something new gets advertised. Adam Curry announced the server at "mtv.com" and his regional carrier was swamped with traffic the next day. The problem is that messages come in from the entire world over high speed lines, but they go out to mtv.com over what was then a slow speed phone line.
Occasionally a snow storm cancels flights and airports fill up with stranded passengers. Many go off to hotels in town. When data arrives at a congested router, there is no place to send the overflow. Excess packets are simply discarded. It becomes the responsibility of the sender to retry the data a few seconds later and to persist until it finally gets through. This recovery is provided by the TCP component of the Internet protocol.
TCP was designed to recover from node or line failures where the network propagates routing table changes to all router nodes. Since the update takes some time, TCP is slow to initiate recovery. The TCP algorithms are not tuned to optimally handle packet loss due to traffic congestion. Instead, the traditional Internet response to traffic problems has been to increase the speed of lines and equipment in order to say ahead of growth in demand.
TCP treats the data as a stream of bytes. It logically assigns a sequence number to each byte. The TCP packet has a header that says, in effect, "This packet starts with byte 379642 and contains 200 bytes of data." The receiver can detect missing or incorrectly sequenced packets. TCP acknowledges data that has been received and retransmits data that has been lost. The TCP design means that error recovery is done end-to-end between the Client and Server machine. There is no formal standard for tracking problems in the middle of the network, though each network has adopted some ad hoc tools.
Need to Know
There are three levels of TCP/IP knowledge. Those who administer a regional or national network must design a system of long distance phone lines, dedicated routing devices, and very large configuration files. They must know the IP numbers and physical locations of thousands of subscriber networks. They must also have a formal network monitor strategy to detect problems and respond quickly.
Each large company or university that subscribes to the Internet must have an intermediate level of network organization and expertise. A half dozen routers might be configured to connect several dozen departmental LANs in several buildings. All traffic outside the organization would typically be routed to a single connection to a regional network provider.
However, the end user can install TCP/IP on a personal computer without any knowledge of either the corporate or regional network. Three pieces of information are required:
- The IP address assigned to this personal computer
- The part of the IP address (the subnet mask) that distinguishes other machines on the same LAN (messages can be sent to them directly) from machines in other departments or elsewhere in the world (which are sent to a router machine)
- The IP address of the router machine that connects this LAN to the rest of the world.
In the case of the PCLT server, the IP address is 130.132.59.234. Since the first three bytes designate this department, a "subnet mask" is defined as 255.255.255.0 (255 is the largest byte value and represents the number with all bits turned on). It is a Yale convention (which we recommend to everyone) that the router for each department have station number 1 within the department network. Thus the PCLT router is 130.132.59.1. Thus the PCLT server is configured with the values:
- My IP address: 130.132.59.234
- Subnet mask: 255.255.255.0
- Default router: 130.132.59.1
The subnet mask tells the server that any other machine with an IP address beginning 130.132.59.* is on the same department LAN, so messages are sent to it directly. Any IP address beginning with a different value is accessed indirectly by sending the message through the router at 130.132.59.1 (which is on the departmental LAN).
Keep computer up2date
How to keep your Windows computer up-to-date
Install high priority updates
Microsoft Update is the online extension of Windows that helps you keep your computer up-to-date. Microsoft Update includes updates from Windows Update and from Office Update, in addition to updates for other Microsoft products and for third-party device drivers. Use Microsoft Update to install updates for your computer’s operating system, software, and hardware.
New content is added to the site regularly so that you can obtain recent updates and fixes to help protect your computer and to keep it running smoothly. To use the Microsoft Update site to install all critical updates for your computer, follow these steps:
1. Connect to the Internet, and then start Windows Internet Explorer.
2. On the Tools menu, click Windows Update.
3. If Microsoft Update is not installed, click Microsoft Update. Otherwise, go to step 7.
4. On the Try Microsoft Update today Web page, click Start Now, and then click Continue on the Review the license agreement Web page.
5. In the Security Warning dialog box, click Install to install Microsoft Update.
6. On the Welcome to Microsoft update Web page, click Check for Updates
7. On the Keep your computer up to date Web page, click Express to install high priority updates.
8. On the Review and Install Updates Web page, click Install Updates, and then follow the instructions on the screen to complete the installation.
9. After you install the high priority updates, you can repeat these steps to install other updates. To do this, click Custom on the Keep your computer up to date Web page. Then, you can select updates from the sections that are listed on the navigation pane.
Automatic Updates feature
loadTOCNode(2, 'summary'); You can also use the Automatic Updates feature to install updates. By using Automatic Updates, you do not have to visit the Microsoft Update Web site to scan for updates. Instead, Windows automatically delivers them to your computer.
Automatic Updates recognizes when you are online, and searches for updates from the Windows Update Web site. An icon appears in the notification area at the far right of the taskbar every time that new updates are available. You can specify how and when you want Windows to update your computer. For example, you can configure Windows to automatically download and to install updates on a schedule that you specify. Or you can have Windows notify you when it finds updates that are available for your computer, and then download the updates in the background. This enables you to continue to work uninterrupted. After the download is completed, an icon appears in the notification area with a message that the updates are ready to be installed. When you click the icon or the message, you can install the new updates in a few steps. For more information about the Automatic Updates feature, click the following article number to view the article in the Microsoft Knowledge Base:
Download Windows updates
loadTOCNode(2, 'summary');Administrators can download updates from the Microsoft Download Center or the Windows Update Catalog to deploy to multiple computers. If you want to obtain updates to install later on one or more than one computer, use either the following Web sites.
Windows Update Catalog
loadTOCNode(3, 'summary');
For more information about how to download updates from the Windows Update Catalog, click the following article number to view the article in the Microsoft Knowledge Base:
Microsoft Download Center
loadTOCNode(3, 'summary');
For more information about how to download files from the Microsoft Download Center, click the following article number to view the article in the Microsoft Knowledge Base:
Install and run Microsoft Baseline Security Analyzer (MBSA)
loadTOCNode(2, 'summary');You can use Microsoft Baseline Security Analyzer (MBSA) to centrally scan Windows-based computers for common security misconfigurations and to generate individual security reports for each computer that it scans.
For more information about how to obtain and use MBSA, visit the following Web site:
Install multiple Windows updates or hotfixes with only one restart
loadTOCNode(2, 'summary');Administrators and IT professionals can install multiple Windows updates or hotfixes with only one restart. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
Programming languages
Programming languages
Programming languages provide various ways of specifying programs for computers to run. Unlike natural languages, programming languages are designed to permit no ambiguity and to be concise. They are purely written languages and are often difficult to read aloud. They are generally either translated into machine language by a compiler or an assembler before being run, or translated directly at run time by an interpreter. Sometimes programs are executed by a hybrid method of the two techniques. There are thousands of different programming languages—some intended to be general purpose, others useful only for highly specialized applications.
What's the Computer
What's computer?
A computer is a machine for manipulating data according to a list of instructions.
Computers take many physical forms. Early electronic computers were the size of a large room, consuming as much power as several hundred modern personal computers.[1] Today, computers can be made small enough to fit into a wrist watch and be powered from a watch battery. Society has come to recognize personal computers and their portable equivalent, the laptop computer, as icons of the information age; they are what most people think of as "a computer". However, the most common form of computer in use today is by far the embedded computer. Embedded computers are small, simple devices that are often used to control other devices—for example, they may be found in machines ranging from fighter aircraft to industrial robots, digital cameras, and even children's toys.
The ability to store and execute programs makes computers extremely versatile and distinguishes them from calculators. The Church–Turing thesis is a mathematical statement of this versatility: Any computer with a certain minimum capability is, in principle, capable of performing the same tasks that any other computer can perform. Therefore, computers with capability and complexity ranging from that of a personal digital assistant to a supercomputer are all able to perform the same computational tasks as long as time and storage capacity are not considerations.
Internet Services
Internet Services
Most of these Internet Services operate on the client/server model or concept. A computer is a client if it is receiving files, and is a server if it is sending files. Another way of putting it is you, your computer, and the corresponding software for each type of service are all clients. A server is a software that allows a computer to offer a service to another computer. The computer on which the server software runs is also called a server. To gain access to the Internet most people open an account with an Internet Service Provider (ISP) in their area. To connect they "dial-up" to their ISP's server and "log-in" with their account name and password. If you noticed, these services are loosely and interchangeably used as nouns and verbs, i.e. "please e-mail me."
Electronic Mail
E-mail, so far, is still the most popular service of the Internet. Most users get acquainted with the Internet using this service. It is better than "snail mail" by post because your message can be transmitted in seconds. It is better than telephones because the recipient doesn't have to be around to receive the message. A person also has the option to read and respond to the messages at one's convenience. Cheaper than long distance phone calls, some people are even able to send and receive e-mail wherever they go when they travel as long as they have access to a connected computer. Better than fax, through e-mail people can send forms, documents, colored pictures, etc. as attachments.
Mailing List
Listserv, a popular type of mailing list, is short for "list server" and is based on the e-mail protocol. As an electronic mailing list it is very convenient when somebody wants to send a message or newsletter, for example, to many people at once. There are thousands of listservs for every imaginable purpose, interest, service, and information like online newsletters, online sales or services, and class listservs. To join a listserv means to be included in the mailing list. You send an e-mail saying you want to subscribe and you will henceforth receive announcements, notices, and information through your e-mail inbox.
Newsgroups
This is the Internet equivalent of a discussion group or an electronic bulletin board. There are newsgroups for every conceivable topic and more, from educational technology and Brazil culture to stamp collecting and mountaineering. Those with specific hobbies or unusual interests are quiet happy to have this service in the Internet when there are so few people in their area to discuss their interests with. You can usually tell a newsgroup by its name. Computer newsgroups start with comp as in comp.apps.spreadsheets. while recreational newsgroups start with rec as in rec.arts.cinema. The others are alt for alternate, soc for social, sci for science, and news for news.
Some newsgroups are moderated, others are not. If it is moderated a human moderator screens all messages and decides if these are worth posting. Discussions can be "threaded." For example, in a newsgroup for beer (alt.beer), one member might ask about good beer pubs in England and another will start discussing how to keep a beer fresh. More than one threaded discussion can occur at the same time with different members posting their opinions and reactions to either one or more threads.
Chat
Another popular form of communication over the Internet. Unlike e-mail, listservs, and newsgroups, chat allows people to converse in "real time." People may actually see you type your questions and responses. Chats are also organized in chat channels and chat rooms according to different factors. There are chat rooms for "techies," cat lovers, singles, etc.
FTP
File Transfer Protocol is the standard method for transferring files, whether downloading or uploading, to and from your computer with another computer on the Internet. It is fairly simple to use and is the most popular way to download software and other files from the Internet. All the files in this web site -- the HTML, graphics, etc. -- were uploaded into the Web using WS_FTP95. There are private FTP sites that require you to log-in with your account or user name and password before you are allowed to enter. There are also anonymous FTP sites that allow you to enter using "anonymous" as your user name and your e-mail address as your password.
Telnet
Telnet is short for "terminal emulation." It is one amazing feature of the Internet that lets you use the resources of another computer in another part of the world. This is done by remotely logging to the distant computer which is called the host. Once you are connected you can operate a remote computer using your keyboard. Some systems require you to log in as a "guest" and others require your name and address, or user name and password. The telnet is most useful to access the databases of public services like library catalogs and government directories. Telnet also allows you to access your e-mail account if you can remotely log in to your ISP's server computer.
The World Wide Web
The World Wide Web is one the latest information service to arrive on the Internet but is arguably the technology that revolutionized the Internet. It is the fastest growing and most exciting feature. People who "surf" or "browse" are describing activities on the WWW. Other words pertaining to the Web are homepages, websites, URL, HTML, and HTTP. This section certainly deserves a page or two of its own so please click on the "Next" button to proceed.
Overview of the Internet
What is an Internet address?
As you have learned how messages are transmitted from one computer to another, every computer in the Internet must have a unique and specific address. An Internet or IP address, as it is sometimes called, consists of four numbers separated by periods. The smallest address would be 0.0.0.0 while the biggest would be 1234.5678.9101.1121. Don't worry, only computers are expected to remember all these numbers without getting confused. For humans, we use the Domain Name System (DNS).
What are domains?
Like IP addresses which are numerical, the alphabetical domain names are also separated by periods or dots. Thus, the U.S. Library of Congress will have an IP address of 140.147.248.7 and the domain name will be www.loc.gov.
Domain names have the format: hostname.subdomain.top-level-domain. My school's domain name, for example, is ocean.otr.usm.edu. This naming structure will give you clues about the address. Ocean is the name of the host computer, otr stands for "Office of Technology Resources" which manages the system, usm is the abbreviation for University of Southern Mississippi, the sub-domain, and edu signifies that this is an educational institution. The gov for the Library of Congress indicates it is a government institution.
Here are the existing top-level domains in the Internet:
- com - commercial
- .edu - educational
- .net - network
- .org - organization
- .gov - government
- .mil - military
Other countries sometimes add their codes at the end, such as .au for Australia, .ph for Philippines, and .fr for France, th for Thailand.
Spam mails
Spam
Spam is unsolited junk e-mail sent to large numbers of e-mail addresses. It is used to promote some product or service and many spam e-mails are pornographic in nature.
Spam Prevention
Unfortunately there are not very many good ways of preventing spam other than keeping your e-mail address secret. It should be kept at a level of security somewhere between your phone number and your social security number. You should be careful about who you give your email address to. Many companies will sell your email address to spam lists, thus making it available to spammers.
I currently use three email accounts as follows.
- The first account is the one I give to personal acquaintances.
- The second account I give to companies that have a privacy policy that I am fairly certain won't sell my e-mail address.
- The third account, I give to companies that I believe I cannot trust to sell my information. I don't worry if these companies can contact me.
I expect to change the third account pretty often, but hopefully the first two will last several years without much spam. The third account may be through a free internet email account service such as hotmail or yahoo.
Managing Spam
Besides keeping your e-mail address secret, the next best spam relief are programs that help you manage spam. Spam can be filtered at the mail server with some programs or they can be a program that plugs into your e-mail client program such as Outlook or Outlook Express. Basically these types of programs filter spam based on several characteristics such as:
- The subject line
- The address of the sender
- Some programs scan the message content and consider length or wording.
Unfortunately none of these scanning methods are 100% accurate although some claim to achieve success rates into the upper 90 percentile. What most of these programs do is to create folders for "friendly" mail or "unfriendly" mail. The friendly mail is put into one folder, unfriendly mail is put into a second folder and there may be a third folder for unknown mail. Unfriendly mail is automatically deleted after some period of time. The capabilities and handling of the mail will vary from program to program. Some that I have considered using include:
- Qurb
- I Hate Spam
- Spam Assassin
There are various opinions about what works when fighting spam. For more information and articles about how to fight spam you can find links to articles at Computer Technical Tutorials Spam .
Spam for Webmasters
If you are a webmaster, spammers will send spam to your domain by sending it to general possible accounts such as administration@yourdomain.com. One way to prevent this is to configure your account with your hosting provider not to respond to undeliverable emails and just automatically delete them. This is called a "::blackhole" setting. The only problem with this is that spammers will still use your bandwidth that you pay for to send you their junk, even though your server deletes them. As spam gets more excessive, it may increase bandwidth costs for webmasters thus discouraging some sites from operating.
Why Spam Should be Illegal
When you connect to the internet, you are paying for a specific service for your use. This service costs a specific amount of money and provides a certan connection speed to the internet. This connection speed indicates your bandwidth. The greater the connection speed, the higher the bandwidth. The higher speed connections cost more money. At this poiint you have paid for the privilege of surfing the internet with your web browser, sending and receiving e-mail, and other activities. The speed at which you can do this is limited by your bandwidth and how fast you can click pages or send or receive e-mail. Consider the Following diagram:
Each person has a connection to the internet. If the person on the right chooses to use their connection to send e-mail or junk e-mail (spam), that is their choice. They are paying for their connection and they are willing to use it in that manner.
If the person on the left does not want to receive spam, but wants to read personal e-mail and surf the internet, they are willing to receive only personal e-mail. If someone is sending them a lot of spam, they will need to wait for the junk e-mail to be delivered before they can read much of their personal e-mail. They are an unwilling participant regarding the unsolicited e-mail they are receiving. Not only is their connection being used by someone else, but it will take them additional time to sort the mix of e-mail out to get to the mail they want to read. If the receiver had willingly stated that they were interested in receiving the advertisements, it would be another matter.
Of course the sender of the spam is not using all the spam receiver's internet connection, but the spam receiver does not get the opportunity to use their connection in the way they fully intended even though they were the one paying for it. This is the same as stealing even though the effective amount may be small. Imagine, how rich you could be if you could only steal a fraction of a cent per day or week from everyone who uses the internet. That's why spam should be illegal.
Someone may argue that spam is the same as junk mail sent through the postal service so why would it be stealing. This is not true since the sender of mail through the postal service pays for the cost of both pickup and delivery. On the internet, the sender pays for the cost of pickup and the receiver pays for the cost of delivery.
The Real and Permanent Solution to Spam and Viruses
Unfortunately a permanent and good solution will take years to implement. A new mail protocol (method of sending e-mail) must be developed by the internet community and then e-mail servers must be modified to handle that protocol. The changing of the e-mail servers will take the most time.
I believe all e-mail should be digitally signed by the sender in order to be delivered. This way the sender cannot be faked and everyone must take responsibility for their own e-mails. However to get this to work right someone must find a way to keep viruses from being able to digitally sign your e-mails for you automatically. A bug in your e-mail client may allow a virus to digitally sign your e-mails causing this type of solution to be ineffective, however, in this case, there would be no doubt as to who has the virus.
Some Proposed Solutions that Won't Work
- Paying for each e-mail sent - This solution will not work because it forces people to pay for services that they have already paid for. Additionally it will not prevent spammers from using poorly configured servers to send spam illegally. It will most likely force victims (those who get viruses and administrators who have spammers illegally relay mail through their mail servers) to pay for the additional e-mail. On the brighter side, it may force more administrators to lock their systems down better and force computer users to be more careful about getting viruses. If this were done, I would think it would make the most sense to allow a limited amount of email to be send on a monthly basis for free.
- Reverse address to name lookup - Some ISP's want to use a check that looks at the address the mail came from and determine the name of the server. If the name does not match the name advertised by the sending mail server, then the e-mail is assumed to be spam and dropped with no notification to the sender. Not only does this violate the rules (protocol) governing the internet for sending e-mail, it will cut down or eliminate the ability for web based programs to automatically notifify users at some websites about events. For instance forum sites will notify when someone has posted an answer to a question. If the user's ISP uses reverse lookup, the user may never see the email from the forum website where they asked a question.
Template by Oriol Sanchez | blogger template by blog forum
