Computer Info
Types of Computer Networks – LAN WAN MAN and Area Networks
A computer network is the practice of linking two or more computing devices together for the purpose of sharing data. Networks are built with a mix of computer hardware and computer software. This interconnected system will share services and interact through a communications link.
A computer network is very helpful in a business. Most of the time a business will have more than one computer set up and it often very beneficial to network all of the computers in the office. A local area network (LAN) will connect your company’s computers. This will allow them to share and exchange different types of information. If you haven’t considered networking your office computers, listen to these reasons.
There are several types of computer networks. A computer network can be very simple, such as only connecting two computers or a computer and a printer, or it can be very complex, connecting millions of computers and devices. Here is a list of different computer network types.
The smallest type of network is a Personal Area Network (PAN). This type of computer network connects a computer to a number of devices. These devices may include, but are not limited to, printers, PDAs, and telephones. Usually these are located very close to a computer. A Local Area Network (LAN) is used to network a small geographical area. An example of this type of computer network is a home network with two or more computers or computers that are connected in a workplace. A version of a LAN is a Wireless Local Area Network (WLAN).
A Campus Area Network (CAN) is ideal for a university but they are also found in industrial facilities. This type of computer network connects computers in a number of buildings. This is generally accomplished through bridging and routing. A Metropolitan Area Network (MAN) consists of any number of interconnected LANs and WANs but it will not extend certain boundaries, such as those of a town, city, or metropolitan area. Many of these are operated at public utilities and are used by businesses and individuals in the area.
A Wide Area Network (WAN) is a step up from a MAN. This type of computer network can cross metropolitan or even national boundaries. The best known WAN is the Internet. This computer network uses routers and public communication links to carry data. Many WANs are run by private companies and restricted, unlike the Internet. Although these are the MAN types of network that most users come across there are other computer networks ranging from as small as a Desktop Area Network (DAN) to a very large Global Area Network (GAN).
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Home Computer Repair – Do It Yourself?
about 1 day ago - No comments
Home computer repair is not brain surgery! Most computer repairs can be broken down into two specific areas, software and hardware. Now I do admit that in some people’s hand, a screwdriver can be a dangerous object. But if you can change a light bulb without shocking yourself, I’d bet you could swap out a computer part. Software gets a little trickier but is still within the grasp of most computer users.
I’ve been involved in computer repair in one way or another for over 25 years. The three major repairs I get called for on a weekly basis are:
Spyware/Malware Issues
Hardware failure (power supplies, hard drives, and ram usually)
Computer boot problems (lost password, toasted OS, hardware failure)
All of these can be quite a challenge depending on the value and risk of losing important data, which can be anything from tax records to photos. Any computer can be repaired; it just depends on time and budget. But not all data can be rescued. If a hard drive suffers a catastrophic hardware failure, data recovery is doubtful (unless you want spend 100’s if not 1000’s of dollars for special services).
So the best scenario in any home computer repair solution is have a good backup of your important data before you start any repair. I never work on anything for over an hour without immediately backing it up on another media (USB thumb drives are only about $30 for up to 5 gigs of storage and CD or DVD prices are under a buck). I learned the hard way very early in my computer using experience. It’s much easier to deal with any home computer repair if you don’t have to worry about important data. *Please, backup your data right after you finish this article and start doing it on regular basis.
When you have a secure backup, the home computer repair is a matter of a little investigative work (to determine the real issue – sometimes Windows will point you in the wrong direction) and coming up with a good solution. Let’s look at the best way to prevent each of the three most common computer repairs and if you already have the problem, some possible solutions.
Spyware/Malware – Two good preventive measures to eliminate Spyware and Malware is to keep your OS (normally Windows) up to date on security patches from your friends at Microsoft. This is pretty easy to do if you turn on Automatic Updating in your Security Center (go to Control Panel, click on Security Center, then check that Automatic Updates is turned on). The other is to make sure you have a good Anti-Virus software installed and it gets updated automatically. These two programs give you about a 93% solution.
Another 5% can be addressed with Anti-Spyware software such as Windows Defender (free from Microsoft, just do a search for it on your choice of Search Engine) or Spybot, a free program from www.spybot.info that does a good job too. Where’s the last 2%, well there is no 100% solution I’m sorry to say. Although common sense on where you surf, what email you open, and where you click can generally keep you safe.
What if you are already infected? Well, there are manual ways of removing Spyware/Malware programs but they aren’t pretty and involve a whole lot of searching around and rebooting in safe mode. If you search on the offender (normally most have a common problem) you can find a manual solution. If you would rather skip all that hassle, the most effective commercial program I’ve seen is SpySweeper. Last time I looked it was only $30 per year and could save you a lot of time and pain. You can find it here: www.webroot.com
Hardware Failure – OK, not a lot of prevention available for this home computer repair. Keep in mind that most modern computer components have a 3-5 year mean failure rate. Depending on how much you use or leave your computer on each day, this time period can expand. I have several testing computers that are very old (plus 7 years) that don’t get used often.
But one point I do want to make is that almost every customer I call on for a hardware failure issues had warning signs before the final crash. Strange noises, computer freezing up, frequent re-starts, etc. are causes for alarm. Don’t wait until the computer literally dies, if any of these events start occurring, go to the proactive mode and replace the power supply, hard drive, or ram. Which one? That’s a challenge, I’ve found that some diagnostic programs can be helpful, but a lot of the time it’s experience.
Basic rules of thumb; Freezing, rebooting can be both flaky power supply and RAM going bad. Power supplies slowly loose ability to supply enough wattage, so if you run fine for the first 30 minutes that’s another tip it could be the power supply. RAM just gets flaky due to constant heating and cooling. It will usually start dying slowly too. Both are cheap to replace but the power supply has anywhere from 8 to 10 plugs you get to keep an eye on when changing out. Any power supply above 250 watt will be fine for most computers, 300 watt is better. Match the power supply or RAM exactly or look up the motherboard requirements if you want to jump up in speed or wattage.
On hard drives, boot failure with the message “no operating system” or similar is almost always a controller or hard drive (some hard drives have controllers on them that go south too). When you go to save or copy files and get an error can also indicate a hard drive issue. Noises of any kind coming from your computer can only be the power supply fan or hard drive. Sometimes you can low level format a drive and bring it back but with the cost being so low on new hard drives, why take a chance.
Boot Up Problems – Number one offender is Windows of any flavor. All versions use a “registry” to manage all software, user, and hardware settings. This is just a fancy database of settings but can easily destroy itself. Open files don’t close properly when there’s a software problem and there goes the database integrity. When you go to reboot, the registry is not readable or flat gone. In Windows XP, there are several files involved in the “hive” (5 to be exact). Any one of these can toast itself, but I always replace all five since they are so interdependent on settings.
The easiest fix, if you can access the Recovery Console, is to find a usable set of back up files and copy them to the current area of access. This sounds pretty simple but the directory structure is fairly long and you have to unhide the backup locations. If you go to Microsoft’s knowledge base here you can read all about the Recovery Console and how to replace registry files: http://support.microsoft.com/search/?adv=1 .
You can run the Recovery Console from Windows XP if it is installed or from your install CD if not. But what if you don’t have an install CD (many computers manufacturers don’t provide one anymore)? You can always use a bootable CD with an NTFS write enabled OS (like Linux) and do the same copying of files recommended in the Recover Console information. If that sounds too scary, you can always borrow some friends Windows XP install CD of the same flavor (Home or Pro) to use Recovery Console. OK, no friends have an install CD and no access or desire to Linux CD, now what?
Well, plan B is to take your hard drive out of the computer, change the little connector on the back of the hard drive to slave (most hard drives have instructions right on the case to show how), and connect it to a working Windows XP computer. Now you have access to the drive with an NTFS write enabled OS. Go back to the instructions on Recovery Console fix and get after it.
If the hard drive won’t even light up or spin, well then you get to install a new one. Most of the new units have a CD that will handle all the details of adding the new hard drive. Then you get to use your Recovery CDs from the manufacturer to install the all the original software on the new hard drive. Don’t have the restore disks? Check with the computer manufacturer and they’ll sell you a set for under $20 usually. Make sure you give the exact model number to get the right software for your unit. Whenever I buy a new computer, if I don’t get a set of recovery CDs, I order them right then and there. That way I’m ready for what ever happens.
So, now you have the basics on home computer repair for the three most common problems. It’s not that hard for most people, just take it slow and read the instructions. Push comes to shove, find a friend who may have a little more experience to help. You buy the pizza and they provide a little experience and moral support.
Connected Via Computer Network
about 4 days ago - No comments
Most of us remain ignorant over how a computer works. We simply just turn on the computer and connect to the internet to access various websites. However, have you ever wondered how we can log on to the internet?
Basically, you are connected by a computer network which is divided into two major categories. They are the client/server network and peer-to-peer network. In the client/server network, there is a computer which plays the major role known as server whereby all the files, data in the form of web pages, documents or spread sheets files, videos, database and resources are kept. Other computers which get information and data from the server are therefore known as client. Hence the term client/server network whereas in the peer-to-peer network, all the computers play equal roles because no computer act as the centralized server.
In a computer network, there is something called a network topology which describes the structure or layout of a network. Some of the network topologies are described as the star, bus, ring and mesh structure. For example in the star topology, all the computers in the network are connected by a centralized device such as hub or switch which form a ‘star structure.’ However if one of the hubs fails to function, then the computers within the network will lose their connectivity and communication.
Using the same principle of language as a form of communication, computers too have their communication language known as protocol. For example, a form of protocol is known as the TCP/IP protocol which is also the most commonly used protocol and it consists of a few protocols. The data flow is regulated by seven logical layers called the OSI layers. They are the Application layer, Presentation layer, Session layer, Transport layer, Network layer, Data Link layer and Physical layer. The Data Link layer is unique because it can be divided into sub-categories which are the Media access control sub-layer and logical link sub-layer.
10 Top Reasons Why I Have to Upgrade My Computer
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The rate at which technology is improving is very fast and in the time you get comfortable with the computer hardware you have bought, several new and improved models appear in the market. While some people prefer to keep their computers state of the art, most of us have a ‘If it isn’t broken, don’t fix it’ attitude when it comes to upgrading or replacing our computers.
This is a strategy that could prove expensive in the long run. It is always better to upgrade your computer on a regular basis, especially if you have had it for over 2-3 years. Even if your computer has had a largely trouble-free existence, you really need to consider periodic upgrades and here are the reasons why you must dos so:
1. Increase in Processing Speed – This is one place where you really get to notice an improvement in performance. If you are upgrading from a Celeron 433MHz processor to a Pentium 4 1.6GHz, you would really notice the difference in performance!
2. Faster Memory Access – Improvements in CPU speed are usually accompanied by improvements in the speed at which data transfer occurs between the CPU and RAM. This is another area that provides an improvement in performance.
3. Size and Capacity improvements – Technology drives a reduction in component size coupled with an increase in storage capacity. This means that a RAM card or Hard disk of the similar size as the older ones in your computer could have double the capacity!
4. Software Compatibility – Many of the new software packages you may wish to use in order to improve your productivity or entertainment experience may not function well on you old computer. It is better to upgrade your computer to enjoy the benefits of new software fully.
5. Obsolescence of Hardware – As your hardware gets older; getting a replacement will get more difficult once manufacturers begin phasing out the production. With improvement in technology, the older hardware becomes cheaper initially and becomes expensive as supply dries up.
6. Technical Support Issues – Many manufacturers stop providing technical support for older components as they cease production. The older your computer gets, the harder it is to find help in fixing it when it malfunctions.
7. Development of New Hardware – New hardware products appear in the market frequently that revolutionize your computer experience and are based on newly developed technology. The chances of your old computer supporting new devices are very low.
8. Faster Devices – Your old computer may not be in a position to accommodate the speed at which the new devices communicate.
9. New, Fast Communication Protocols – You may not be able to implement newer or faster communication protocols in your old computer because the hardware is unable to support them.
10. Operating System and File Format – Your old hardware may not be able to run newer operating systems and some of the file formats may not be supported.
Types of Computer Networks
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There are different types of Computer Networking that you may need for your home or office. To begin with you have the option of a wired or wireless computer network. These types of networks differ. A wired computer network will have copper or fiber optic cabling running between computers while a wireless network uses radio waves and/or microwaves to maintain communication channels.
A client/server network works by using client devices, typically PCs with network software applications installed that request and receive information over the network. The server device will usually store files and databases and includes more complex applications like Web sites. These devices often feature high-powered central processors, more memory and larger disk drives than the client devices. Two examples of client-server systems include Web browsers and servers.
In addition to these types of networks there are also types of area networks. These are categorized by their scope or scale. Some area network types include:
• LAN – Local Area Network
• WAN – Wide Area Network
• WLAN – Wireless Local Area Network – a LAN based on WiFi wireless network technology
• MAN – Metropolitan Area Network – a network spanning a physical area larger than a LAN but smaller than a WAN, such as a city. A MAN is typically owned an operated by a single entity such as a government body or large corporation.
• CAN – Campus Area Network – a network spanning multiple LANs but smaller than a MAN, such as on a university or local business campus.
• Storage Area Network – connects servers to data storage devices through a technology like Fibre Channel.
• System Area Network – links high-performance computers with high-speed connections in a cluster configuration. Also known as Cluster Area Network.
These are just a few of the various types of area networks. LAN and WAN were the original categories of area networks but through the evolution of technology we have been forced to keep adding more and more types due to the ever-changing field.
A LAN network will connect devices over a relatively short distance. This may include a building, school, or home that will contain a single LAN. Sometimes one building will contain a few small LANs and on the other hand a LAN may span a group of nearby buildings. A WAN spans a large distance. The Internet is the largest WAN as it covers the Earth. A network device called a router will connect LANs to a WAN. These are typically not owned by any one organization like LANs but are under a distributed ownership and management system.
Computer Repair – Is It Hardware, Software Or Both?
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Computer repairs can involve hardware repair, software repair, a combination of both, and or probably some troubleshooting. It\’s not for the faint of heart; if you are pulling your hair out, you may want to consider doing something else about it like, call the Geek Squad. Basically what we are attempting to get our machine to load properly. When a PC starts up, first it tests all the connected hardware and then looks for the software that it needs to load in order to run properly. If the machine does not power up, or the machine powers up, but does not load, then we have a pretty good idea as to what the problem may be.
All of the parts of your computer that you can physically see and touch it is your hardware. It takes quite a bit of well engineering and design for all those components must work together well. Sometimes components can be damaged by external forces. To clarify external forces can mean a few things. Shock damage or the effect of being dropped can certainly cause damage to a component therefore rendering it inoperative. Also I would like to include a power surge, over voltage, over temperature, under temperature, water emersion, excessive moisture, acts of nature, etc external forces which can cause failure of a component.
Any code that the machine deals with in the form of data is the software. The operating system, the software, drivers, and all digital, is the code. Although code can be damaged by the result of external forces on a storage device, computer software code is susceptible to a whole different variety of potential means of damage. For instance if you install the wrong driver for the wrong component, the machine will not be able to communicate with the device correctly or at all. If in the case that the machine caught some type of virus, which damaged the code, or worse, compromised code that causes the hardware to have problems, It would be a great Idea to replace damaged code with correct code. Healthy software is crucial to the successful operation of a computer. Just to illustrate this fact, Let\’s format the hard drive and see what the computer does next.
The thing that you have to consider in computer repair is that if there is a change to some of the hardware, you are going to find that you will probably have to make some changes to the software which you have on it in order for it to work correctly. Type of changes that typically need to be made are installs and reinstalls. If there is some troubleshooting involved, I would start from the hardware and work through the software issues. When we start an IBM compatible machine, the unit does its POST. A POST is a Power On Self Test. The machine does this to check if all the components that are connected to the motherboard are functioning. If the machine fails this test, right off the bat you know you have a hardware problem. If this occurs, the machine usually beeps a couple of times and displays nothing on the screen.
Given that the machine successfully passes its POST, and it goes on to seek boot information from the hard drive, you are one step closer to a functioning machine. If in the case that the machine does not boot its operating system, there are a few questions that must be answered. Is there currently an operating system installed? Is the correct boot device called for in the BIOS screen? If you do have your operating system installed and it\’s not loading, Is your BIOS calling for the correct device to load the operating system software? Is there boot information on the drive? If there is no operating system, or if the operating system is not correctly installed, then you may want to consider possibly formatting the hard drive, doing a fresh clean install of the operating system and then trying again.
In order for a PC to load correctly, a few things must happen. First the computer must recognize all of the connected components. All the connected components must be compatible with the motherboard. When the computer does it\’s POST and passes to the next step, this signifies that all the components connected to the machine are compatible and in working condition for the most part. Secondly, the computer must have an operating system with all necessary drivers for all the components to be able to function at maximum potential capacity. When getting into a computer repair project, the main things to consider are, is this a hardware repair, software repair, or both.
Hardware Asset Management – Managing Your Computer Inventory
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To better manage your IT asset you need a tool that gives you instant IT Visibility — the detailed configuration you need of ALL of your computer assets. You should be able to easily view the updated configuration and physical location of each computer, server or laptop you have on your network. Tag each asset and assign it to users and technical owners. These hardware hardware properties includes CPU, BIOS, disks, sound cards and many others, and know exactly which software titles are installed and used on each of your computers.
When selecting an hardware asset management tool you should seek a tool that helps you track the hardware across your network, allowing you to know everything that happens on your network, with your computer assets and allowing you to easily maintain and access a full history of changes.
Corporations, small business, government agencies or educational institution, all require a comprehensive solution for managing software and hardware assets, controlling expenses, and automating license compliance. These are the key areas that you need to focus on when selecting a solution for your organization:
Inventory hardware assets, including computers, software, servers, laptops, and mobile devices that connect to your network. Get Instant IT visibility: View updated configuration and physical location of each computer, server or laptop. Search every hardware asset by CPU, by operating system, by vendor and many more. The Compliance Manager ensures IT compliance by tracking computers and software that are installed on your network.
Implementing an hardware asset management system will help you gain better visibility into your hardware assets and better control your IT infrastructure resulting with reduced IT costs.
Overview of Computer Networking
about 2 weeks ago - No comments
A group of interconnected devices sharing information and resources together is known as network. Or, sharing information and resources between devices is called computer networking.
Advantages of Computer Networking:
Connectivity and Communication: Networks can connect different computers and the users of those computers. This makes the transmission of business or non-business information easier, more efficient and less expensive than it would be without the network.
Data Sharing: One of the most major uses of computer networking is to share the data among multiple users. It enables thousands of users to share data much more easily and quickly.
Hardware Resource: In computer networking, you can also share hardware resources like printer, CD drive etc. Its true that one printer can be placed on the network to serve multiple employees.
Internet Access: The Internet is itself a kind of network, so when you surf the Internet, you are using a computer network.
Computer networking can be of various types as mentioned below:
Local Area Networks (LAN): Local area networks, generally called LANs, are privately-owned networks within a single building or campus of up to a few kilometers in size. They are widely used to connect personal computers and workstations in company offices and factories to share resources and information. LANs are restricted in size as distance varies from 1 to 10 km. Traditional LANs run at speeds of 10 Mbps to 100 Mbps. Newer LANs operate at up to 10 Gbps.
Wide Area Networks: It is a collection of more than two LANs. A WAN is any network that crosses metropolitan, regional, or national boundaries. A WAN as any networks that uses routers and public network links.
Metropolitan Area Networks: A MAN covers a city. The best known example of a MAN is the cable TV network available in many cities. A MAN is smaller than a WAN but bigger than a LAN.
SAN: Storage area network a SAN is a dedicated high-performance network used to move data between servers and storage resources.
How To Become A Successful Computer Networker
about 2 weeks ago - No comments
Job Responsibilities
As a significant part of the IT section in a company, a computer network technician has to see to it that everything from the Local Area Network (LAN) connections to the Wide Area Network
(WAN) connections run efficiently. Also referred to as a computer network engineer, such a specialist has to help plan the employer’s computer network and introduce new features to it, as and when required. Above everything else, a computer network technician requires to have precise knowledge about all the aspects of the company’s internal network since this is instrumental for information exchange. Apart from problem-solving skills, a computer network engineer needs to be adept at installation and configuration tasks.
Training and Education
Most companies search for certified computer network technicians. This means that one needs to have an advanced degree in computer networking to get through such a job. While most universities offer a Bachelor’s degree in computer networking, there are other certificate courses too that a student can make use of. In recent times, a host of online degrees have been launched to meet the educational requirements of students who seek to pursue this job profile.
IT majors like Hewlett Packard have computer networking courses that give students an in-depth idea about working on networks and keeping them up-to-date for the benefit of the employing company. However, online education would be the best option for you if you’re looking at comprehensive study of the subject.
Compensation
Computer network technicians are a class of well-paid professionals. In the United States, the median salary is about $60, 000. Computer networking salary naturally depends on factors like the size of the company, the seniority of the position offered and the responsibilities that come under the purview of the role.
According to some important official reports, the average computer networking salary stands at a little more than $58, 000 per annum. For a junior role like computer support, the salary is about $44, 500 per annum.
Computer Networking Services Florida
about 2 weeks ago - No comments
A computer network is the practice of linking two or more computing devices together for the purpose of sharing data. Networks are built with a mix of computer hardware and computer software. This interconnected system will share services and interact through a communications link. If data is being sent over the system then the individual computers must follow a set of common communication rules in order for the data to arrive at is correct destination. This is also vital for the systems to properly understand each other otherwise data will not be received. These rules are known as protocols.
So, in order for a computer network to be set up properly four things must be present: two or more systems, something to share (such as data), a communications link or physical pathway, and a set of rules for communication or protocols.
Wireless computer networking uses radio waves and/or microwaves to maintain open communication channels between computers. This version of computer networking is a more modern approach and is an alternative to wired networking. The advantages of wireless computer networking are that this involves mobility and the elimination of a copper or fiber optic cabling running between computers. However, a wireless computer network has the potential to have radio interference due to weather, other wireless devices or obstructions.
If you are unsure what type of computer network you would like you can have a trained professional come to your home, business, or other location and have them recommend what you need depending on what you are using your network for. You should always hire a trained computer specialist when setting up a computer network as there may be complications and it can be very difficult to learn how to set up a computer network by yourself.
Buy Quality Computer Hardware Online
about 2 weeks ago - No comments
Computer hardware means the physical part of a computer. No software or program can do anything without proper hardware. Moreover the success or performance of a software program depends completely on the computer hardware being used. So it becomes absolutely important that we buy quality computer hardware.
Now that you have decided to buy computer parts, the next big step is where to buy them from. One tends to always buy from a friendly neighborhood computer hardware dealer. But, with the advent of Internet, one has the convenience of going through literally hundreds of product catalogs and arriving at a purchasing decision.
The Internet is a popular place to check out computer hardware sales, but you must be sure that when you buy hardware (or any purchase) over the Internet, the site offers some kind of security to prevent information about you from being stolen.
Buying a computer part online is often cheaper than buying it from a dealer, as the overhead costs are reduced. This means that you pay less and get more. This is one advantage that has led people in increasing numbers to shop for parts online, especially from a wholesaler. Since the entire sales channel is literally cut in half, you do not pay for the extra margin, which you would have had you purchased the same from a retailer. There is also the convenience factor of shopping online.
In fact, cheap and discount computer hardware is very easy to find online. Whether it is notebook parts, input devices, printer, printer supplies you can find them extensively advertised and sold online.
One should always take care to ensure that the parts that one is buying are genuine. What this means is that one should always buy these computer hardware from a reputed online dealer.
Computer hardware UK offers quality computer hardware online