Sunday, February 14, 2016

Factors to Consider When Selecting Network Topology

A topology refers to the characteristic of communication network, that concern both the physical configuration of the cabling used to interconnect communicating systems and the logical way in which system view the structure of the network which is either physical or logical arrangement of Computers

Below are factors to consider
Cost: Whatever transmission medium is chosen for a LAN it has to be physically installed in the building, this maybe a lengthy process involving the installation of cables and other devices through raceway. For a Network to be cause effective, one would strive to minimize installation cost. This may be achieved by using the proper hardware linking the cables, proper communication devices between the buildings, proper servers and minimizing the distance involved. All these devices will cost you money hence your budget will largely determined what type of Computer topology to adopt

Network Flexibility
One of the main benefits of a Local Area Network is its ability to have the data processing and peripheral nodes distributed around a given area; this means that the Computers, power and equipment can be located close to the ultimate users. Because the arrangement of furniture, internal walls etc in the office is often subject to change. Any topology should allow for easy reconfiguration and these involving moving existing devices including computers, servers etc and easy of adding new system. So flexibility will determine which type to go for



Reliability
The topology chosen can help by allowing the location of the fault to be detected and provide some means of isolating fault. A system with easy of error detection and isolation will be much better than a topology that proves difficult to locate problems in the entire system

Networking Equipment
Topologies might slight differ from one another due to the installation equipment they will need, this is a factor that will influence what type of network topology to go for based on the availability of these items

Network Growth
A topology that have the ability for future  expansion will be necessary while consider the type of to adopt, future growth means more users within an organization leading to additional expansion of the topology, the easier to expand the chosen one the lesser cost will be incurred. So go for one that will help reduces cost during expansion and implementation

Factors to Consider when selecting magnetic tape backup software

There are so many factors to consider when selecting magnetic tape backup software. Below are some of the questions that you need to ask yourself when selecting software.


  • Does this software provide support for the drive I have? 
  • Can the software manage my tape inventory for me? 
  • What type of compression does the software provide to reduce my tape usage? 
  • Can the software create bootable CDs or disks to allow me to completely reinstall as system in case of an emergency? 
  • How easy is it for me to manage the backups? 
  • Can a nontechnical person use this software to complete backups? 

Good backup software will perform the following functions

Multiple platform support
Good software will be able to support other platform ranging from window based platform to non windows operating system. Many software are designed to support window based clients hence going for one that only support windows OS would be limiting when upgrading to a non window based server i.e. Unix, Sun, or AS/400 server computers among others.

Backup and recovery options
You may need a package with a recovery option as this will aid your work and save time while backing up your data, all this depend with your organizational requirements.

How to Choose an Appropriate Digital Camera with a High Quality Camera Lenses

A Digital Camera as the name suggest is capable of capturing, recording and storing images in a digital format. Other than storing digital images new models have Wi-Fi functionality enabled which allows users to transfer images wireless on their preferred social networking sites. If you are a photographer then digital camera with good lenses is all you need, this will help you save already taken photographs on your online photo album for sharing with friends, family members anywhere and anytime around the global

For a digital Camera to be of great value to a photographer it must a have Camera Lenses with the following attributes.

Focal Length: This defines the Camera’s Lens’s angle of observation. There are various types of Lenses available in the market namely fixed focal span lenses which are not zoom-able and sometime referred to as primes, having  a single number  and the zoom lenses with two numbers indicating the extremes of the range. 

The other component of a Digital Camera is the Aperture which describe amount of light gathers by the lens, normally expressed in many different ways including f4, f/4, 1:4 which offer the similar meaning. 

A digital Camera with a smaller number indicates that the lens has a larger maximum aperture which enables it to gather more light. Having a lens with a larger aperture will allow a photographer to capture images in a lower light environment. With a Digital Camera having these lenses you are capable of taking photos indoor with no flash. As you go for a Camera Lens with larger apertures you need to note that their bigger sizes reduce the depth of the field.

The other important feature of a Camera lens is the Image Stabilization(IS) which different manufacturers having different implementation method. Below are some references uses by various manufactures when describing Image Stabilization:-

IS known as Image Stabilization is used by the Canon Company, OIS which refers to Optical Image Stabilization is used by three giant Companies namely Panasonic, Samsung and Fujifilm, VR known as Vibration Reduction is deployed by Nikon, OS which stand for Optical Stabilization and not Operating System is associated by Sigma Company. 

The Optical Steady Shot (OSS) is used by the Sony Company while Tamron uses Vibration Control (VC) to describe the Image Stabilization. The other two features to be considered when choosing a Camera Lenses are the Format and the Lens mount. The Format is the sensor size designed for a lens to use while the mount is used to determine whether your lens will physically fit your digital Camera.

Questions to ask yourself before buying Digital Camera and Camera Lenses
Does the Digital Camera automatically select the most appropriate shooting settings for optimal output based on the environment? Does it have the ability to automatically and smartly select aperture speed based on the shooting surroundings, how much does it bring the subject into focus, how does the Camera react in a low and high light situation. Does the Camera have the capability to allow you select a colour and replace with the best colour for your circumstances? 


Monday, February 8, 2016

Factors to Consider when Selecting a WLAN technology

There are so many factors to consider when selecting a Wireless Local Area Network (WLAN) technology as we are going to discuss below. Before selecting a WLAN on has to consider the technology you support and based on that go through the following check list.

  • What type of standard do you support, there are 3 WLAN standard in the market that you can go for with each having different features as discussed earlier, the standards are the IEEE 802.11a, IEEE 802.11B and the IEEE 802.11g
  • Check on the maximum data rates that each standard support, here is the data rate for each standard the 802.11a support up to 54Mbps, 802.11b support up to 11Mbps, 802.11g support up to 54Mbps
  • Check on the speed of the WNLAN standard, 802.11a has speed of 5GHz, 802.11b has a speed of 2.4GHz and the 802.11g functions at 2.4GHz  
  • Consider the number of channels that each standard will give you as most support from three to 11 channels with 8.02.11a supporting eight to eleven channels
  • Consider the amount of interference each WLAN standard would experience
  • Bandwidth capacity that each standard can support
  • Consider number of access points your network will support
  • Type of security that the selected standard is going to offer most of them support both the WEP and WPA
  • Vendors support for multiple standards into their wireless products. This will give you room to freely test other products on the same platform without interference at all
  • The type of WLAN devices available in the market has to be considered this enables clients to implement networks with readily available equipment
  • Consider the speed of these WLAN devices
  • The cost of devices would also be taken into consideration as you can only use the device you can afford to buy
  • Buying network adapters that support multiple protocols, and this could cost you additional money
  • Support for migration and competing standards problems
  • Consider networks degradation speed as you moves further from an access point, this help to know how weak is the signal of this particular standard compared to the others
  • Type of protocol will influence the type of standard for your WLAN since protocols specifies a variety of speeds at which it can operate
  • Site survey  
  • Security implementations  
  • Future technologies
  • Value-add to the power user

Those are some of the few factors to consider when selecting WLAN technology, check other factors from already established clients near and find out there experience with the technology they are using, consult your wireless network technician on the available types of technologies that you can implement after doing a site survey and remember it’s very crucial for a site survey to be done in order to implement a more satisfying WLAN
 



Factors to Consider When Choosing Magnetic Tape Backup Disk

There are so many factors to consider when selecting the type of magnetic backup, they may directly or indirectly depend on the users and expertise you have in your organization. You will consider factors such the speed, the higher the speed the better and this will reduce time wasting and writing of data will be achieved faster. Other factors organization should consider are

Multiple server backups
Although this would cost you more money to purchase but as an organization you may decide to source for backup agent software, these software increase or aid the speed at which data is being processed and as a result they reduce time taken to save the entire network data
You may need to consider backup agent software to allow a backup to complete in a timely fashion over a network.
 
Database server: You will most certainly need to find a backup agent to manage the database files so your backup can store this critical data.
 
Nontechnical personnel: You may need to document and set a simple rotation schedule so someone onsite can follow instructions on tape management. You can also use an auto loader that only needs to be swapped once per week with new tapes.
 
Large amounts of data: You may need to select an auto loader to provide the appropriate capacity to manage full backups. You may also need to evaluate the connectivity of the backup system to provide the backup function in a timely manner. Full backup over a network from a large capacity file server may exceed the time available for performing the backup.
 
Long-term data storage: Some industries require the storage of data for a long period of time. In this case, you may want to select a rotation strategy such as Grandfather, Father, Son or Tower of Hanoi. These provide for much longer rotation schedules.
 
Small work group: In the case where your small office has no designated server, you'll only be backing up data across the network for the office to a single workstation with an attached tape drive. You may want to consider a simple rotation with full backups every night, assuming the tape media has the capacity to do so. You may also want to run a Round-Robin rotation over two or more weeks. This will provide adequate data protection over a mid-range length of time. Consider doing a monthly backup to store data for longer term.

Factors to consider Before Upgrading Your Computer (PC) Processor

Processor Upgrading
Computers processors sometimes may be upgraded to improve the performance of your computer, which includes the increase in the computer speed and faster accessibility of files and programs. When upgrading your computer processors are some factors to consider before proceeding with the upgrade

Socket CompatibilityWhen buying a processor ensure that it is compatible with the motherboard sockets, otherwise your processor amy not function if they are not inline with each other. Check the computer motherboard insertion slot before buying your processor
 

Processor Speed and Bus SpeedWhen upgrading your computer processor ensure that you buy the right processor with the right speed supported by the bus speed otherwise your processor may not function
Processor external data bus has to be compatible with your current motherboard and without compatible you will have difficult time upgrading the processor


When upgrading the processor one has to consider the Bios Support, if your processor is not supported by the Bios then you will not upgrade the processor which means it has to be supported by the computer Bios. Other factors to consider include computer voltage and the cache type which is supported by the processor you want to upgrade
 

Cost of the processorYou will have to shop around to look for the best deal when buying your computer processor for upgrade. The costly the processor the higher it will cost you to upgrade your computer hence shop around to find a suitable price for a quality processor

Factors Affecting the Performance of Computer Processors

There are so many factors that affect the performance of your processors, these factors will either slow down or increases your processor speed. When the speed is reduced the rate at which data and information processing will be negatively affected and this will result into time wasting. Below are ways that your computer performance would be affected

Math Co-Processor
The Co-processor is used to increase the processors number crunching speed but it does not however increases the speed of simple additions and subtraction. The Math Co-processor increases the speed of calculations involving floating decimal point operation i.e. Algebra and statistics. The negative effect could also be noticed if the Co processor is faulty and can’t process these functions

Clock speed
The frequency with which the processor execute instructions, the higher the clock speed (measured in MHz), the faster the processor. In aging Computers one would realized how slow they can be sometimes, this would result as the slow clock speed experienced by these Computers. If the clock is affected the speed also has to reduce and the overall performance of your machine will be either badly affected or greatly improved. New machines processed data and information much faster because they have brand new clock with high speed
 
Internal Cache
This is a storage area for frequently used data and instructions. The processor contains an internal cache controller that integrates the cache with the Central Processing Unit (C.P.U), the controller stores frequently accessed Random Access Memory (RAM) locations to provide faster execution of data and instructions and therefore a larger cache leads to the perception of a faster CPU.



The Bus
This refers to the system board underlying circuitry. A Bus is defined as an electronic pathway along which signals are sent from one part of the Computer to the other. The processor’s ability to communicate with the rest of the system’s components relies on the supporting circuitry

Below are factors to help increase the processor speed
•    Increase data bus width
•    Perfecting technique
•    Pipelining technique
•    Use of two alternative Arithmetic Logic Units (A.L.U)
•    Use of Floating Point Unit (FPU) the math coprocessor
•    Clock multiplying
•    Memory caching systems

Factors Affecting Computer Networks Growth

There are so many factors that have contributed either directly or indirectly to the growth, among them the emerging better networking technologies have forced organizations to either replace or improve the existing structure. The rapid expansions can be attributed to the following factors

Organization and Downsizing
Many organizations are downsizing their Computing from mini and mainframe to Micro Computers based networks. Downsizing refers to a process that enables organization to replace their traditional mini and mainframe operation with micro and modern technological equipment

Below are some reasons for downsizing 
Cost: organization can save millions of money by replacing large mainframe with a micro Computers based network that is micro hardware and software are cheaper than the older generation requirement
Range of Software: They have a wider range of software than mini or main frame computers. Theses software includes both application and programming software that help both the users and the programmers. The software’s are easy to learn compare to the earlier application.
Speed of processing: Ability to allow decentralized processing which enables Local Area Networks (L.A.N) to be faster than older generation. People within a connected system are able to share data and files within the shortest time possible hence also save time of movement of people from one building to the other
Large storage: In this type of setup both the file server and the stations have storage capabilities; this means that they can both be used for storage purposes. There are also evolving storage equipments for newer generation Computers among them are external storage devices like hard disk, storage tapes etc.
Access to database and electrical mail
The ability to access database of information and for people to communicate electronically oversea distances have also led to growth examples of information database available online are; online news, weather updates, research works, shopping portals among others

Resources SharingThis is the ability to share resources. People on the network are able to share application software and can also share hardware devices to reduce the cost of equipment and software devices acquisitions. The resources can be placed on one centralized place that any person in need of these resources will have easy access to them.

Evolution of Communication StandardsThis is the movement towards networking standards. These standards enable communication between different types of Computers. As the standards evolve communication becomes much simpler, error detection and elimination is done much faster and end users are able to get right data. The new standard also helps increase network performance speeds hence saving time on standard communication


 

  

How to Choose a Dell Laptop Battery

A laptop battery can simply be defined as a Computer component that collect, store and provide power internally to the laptop, its gives the laptop the ability to work without external power source. There are so many factors to consider when selecting a Dell Laptop battery, before buying any of the Dell Inspiration considers the following features.

Compatibility
Is the battery being replaced have the capability of working together with the Dell Inspiron 1501 or any other version that replacement battery is being sorted without any user adjustment of the laptop. Buying incompatible system will only mean that you go extra mile in adjusting and modifying the current system settings and features to be able to work fully. This will require extra cost hiring a technician to modify the settings, incompatible settings may lead to malfunction on the Dell Inspiron 1501 replacement battery and can lead to Laptop damage.

Power Consumption
When buying one of the Dell 1501 Inspiron battery check from the documentation how long it does conserve power when the main power supply is off. Battery made of Ion is known to consume a lot of energy when charging.

DurabilityHow durable is the battery being purchased, how long it will last before buying another battery. Genuine battery can only be bought from Dell authorized dealers, this will guarantee quality and long lasting battery as opposed to buying from unauthorized dealers selling at a lower price but offering substandard Laptop battery. Many people may prefer a cheaper place but this will not solve your battery issues. Spend more on quality products and get a genuine long lasting and money saving product.



Dell Inspiron 1501 adapterYou may be having a good battery but if the Dell adaptor is substandard then your battery shall not last for a long period of time, in fact it may end up destroying your newly bought battery. Check the adapter quality and ensure its support your Laptop. A faulty 1501 Adapter will over heat all the time making it uncomfortable to work with the Laptop. Ensure you get the right adapter for the laptop from any authorized sell dealer. Don’t use incompatible power adapter as this shall cause unforeseen damage to your system.

Those are some of the factors to consider when buying Dell Inspiron 1501 battery, once bought your adapter will and battery will need at most care to last for a good period of time. Avoid replacing your battery very now and then; don’t share your Dell battery with other people as this may cause incompatibility and other related fault issues. When your battery is fully charged, remove the adapter from external power source and utilized the battery power. This will help to prolong the shell life of both your Inspiron 1501 adapter, battery and the laptop. Buying any of the Laptop accessories from authorized dealers where there warrant is given and can be replaced at any time within the warrant period.
 

What are the Uses of Computers Today

Main Computer Uses
Computers perform many uses in our society today and almost all functions both private and public organization uses computer for one reason or the other. Initially tasks were performed manually but with the adventure of computing systems, tasks are being managed and accomplished much faster that ever imagined. Uses ranges from hospitality industry, security institutions, government institutions with household amounting to the larges uses of computers. Today they are being use in many places for different activities as described below.

Business and Financial Records
Payroll records, accounts, inventory format commonly used to display the data in columns e.g. ledger and balance sheet known as spreadsheet. To perform the following tasks
  1. To calculate, check and display their financial data which are easy to read
  2. To experiment with alternative business strategies e.g. affect of wholesale change margins would be on your profits, thus very simple to evaluate the financial impact of such a change
Writing and Editing
Word processing software gives solution to erase making changes to content of materials, making duplicate copies for business and personal correspondence. Word processing is alternative to typewriting but here words appear on screen this can correct mistakes by inserting, moving words down and up as well as spell checking and eventually printing when you are satisfied with your work

Desktop PublishingDesktop publishing uses a more advanced word processing. Allows for more creative writing and page design and also enable achievement of results look professional. Through desktop publish companies are able to produce newsletters, adverts, small books etc. equipped Computer print documents in several different sizes with different typefaces and styles i.e. italics, bold face or superscript. Can reproduce photographs. One can compose, edit and modify each page as much as one wishes


Storage and RetrievalThey are used for storage of information for future use. Good memory can retain information in enormous quantities known as database. You can use database to sort information in whatever form. They stores data in different technologies including CD/DVD, Magnetic tapes backups, off line server among others 

Drafting and Drawing: 
Uses of small Computers with aided design or CAD, software for drawing with architecture to help them with their daily activities. Before drawing were done manually but with the coming of new technologies, things have changed and more work is being done within a short time

Sunday, February 7, 2016

Computer programming languages and generations

Computer programming languages and generations
Programming languages are use to write application programs which are used by end users. The programming languages are generally used only by professional programmers to write programs. The development of programming languages has improved considerably with the ease and ability of programmers to write powerful applications programs that can solve any task in the world today.
Each computer programming language has its own distinctive grammars and syntax and its own manner of expressing ideas. In principle most computational task could be accomplish by any of the languages but the programs would look very different moreover, writing a program for a particular task could be easier with some languages than the others. The various generations of computer programming languages are discussed below.

1st generation languages
The first generation computer language was machine language, all the machine used machine code which consisted of 0s and 1s. Machine language is highly efficient and allows direct control of each operation; however programmers had to write computer programs using 0 and 1. Some of the drawbacks of the first generations languages were
• Programs were difficult to write and debug
• Programming process was tedious
• Programming was time confusing
• Programs were error prone

 2nd generation languages
These were developed in the early 1950s with the ability to use acronyms to speed programming and coding of programs. They were known generational languages were called assembly languages. They had the capability to performs operation such like add, sum. Like machine languages, assembly languages were designed for specific machine and microprocessor, this implies that the program cannot be move from one computer architecture without writing the code which means learning another language where you are to transfer the programs.

3rd generation languages
These were introduced between 1956 and 1963 which saw a major breakthrough in computing history with the development of high level computer languages popularly known as 3rd(3GLS). Example of the 3rd generation languages includes the following
FORTRAN – Formula Translation
FORTRAN was developed in 1956 to provide easier way for scientific and engineering application and these were especially useful for processing Numeric data.

COBOL – Common Business Oriented Languages
COBOL came into use in the early 1960. It was designed with business administration in mind for processing large data types with alphanumeric characters which were mixture of alphabet and data and does repetitive tasks like payroll. The other language was BASIC. These were the early computer programming languages in the early history of computers, since then there has been improvement and this will be discuss later.

Learn More about Computer Communication and Networking

Simple Definition about Computer networking and communications

Network - refers to interconnection of system/computer with a view of sharing resources/communication purposes

Why share resources?
1. Saving of cost Interconnected computers enable limited resources to be access by many people within a work place or globally. This save on equipment cost, example if you have 10 employees and want to purchase a printer for each of them, you interconnect the employees and buy 1 printer and connect to the 10 computers in the network.
2. Timely data retrieval. Networking help to bring resources at more centralized place which are easily accessible, resources are placed at one centralized place which any one who wants can reach
3. Security/Integrity of data. In secure interconnected computers it safer to transfer data across networking to avoids the tendency of your devices getting stolen
4. Research Research has become very easy with the reach of information available over the internet. This help to save time of undertaking a research that also into saving money and doing a timely report
5. Entertainment Entertainment has become a click of the mouse, you don't have to visit movie cinema as all this movies are available over the internet
6. Business/Trade It has become more lucrative to do business online because millions and millions use the internet daily as compared to shopping supermarkets and shop. Buying a car from one continent to another has become a click of the mouse without having to travel to that continent.
7. Consultancy Expertise is offering their knowledge over the internet for money. Working has become internet commuting that you only need to have internet connection and market your resume globally

We are going to discuss the common types of network we have
a) L.A.N (local area network)
b) W.A.N ( Wide area network)
c) M.A.N (Metropolitant Network)
d) Peer to Peer Network e) Client server Networks


Characteristics of L.A.N
•    Refers to inter connectivity of computers within a given radius of 25 to 30 miles.
•    They are always within a building
•    Characterized by same transmission medium e.g. broadband
•    Characterized by same operating system example running on a window platform of same version.
•    They run on a special cables e.g. Fibre, optic cables
•    Uses same transmission techniques could be digital (0&1)broad band analogue(waves)

Advantages
•    Fast transmission of data
•    Low cost of establishment compare to other types of network
•    More Secure because it's not connected to the public
•    Easy to set up since media of same characteristic are needed Disadvantages
•    Doesn't support many users since it's within a radius or a building.
•    Is limited to resources

Characteristics of W.A.N
•    Connect computers to a large geographical area normally within a town or a country
•    Support many users
•    Transmission of data is slow
•    Security is compromised since its for public access
•    Needs high specialized people to run it
•    Need high cost of establishment
•    Sharing of resources is unlimited

Characteristics of M.A.N
•    Share the same characteristics of a L.A.N
•    Might be public or private

Peer to peer Networks
•    Refers to computers interconnectivity with no dedicated server to perform any routine work
•    Has got less than ten computers
•    Can exist in all topology
•    Sharing of resources dependent on the users themselves
•    Chaotic network - no centralized management of resources
•    No administrator to run the network
•    All the computers are equal and known as servers
•    Normally each computer function as a client or a server

Characteristics of peer to peer network
a) Cost - the peer to peer network is relatively simply because computer functions as both a client and a server and no need for a powerful central server.
b) Size - It has got no more than ten computers
Factors to consider before designing a Peer to Peer network
1. where there are ten or less ten users of the network
2. where security can be compromised
3. where users are in the same L.A.N
4. If the growth of an organization network is not anticipated in the near future
5. Training - since all computers in the network can both be server and client , users will have to be trained before they are able to function properly as both users and administrators in that computer
6. Security - security consist of setting a password on resources such as directory that is shared on the network because all peer to peer users set their own security and share any existing computers.
3. Server requirement - all computer works as either server or client
4. Sharing resources - where all resources will be accessing by all user
5. Administrators if you intend not to have administrator
Learn about Computer and related information here


Computer Network Devices Adavantages and Disadvantages of Networking Devices

Computer Networking Devices

To create a flexible enterprise internetwork, it is necessary to interconnect individual local area network data link and wide area networking facilities, there are a number of different types of devices that can be used to accomplish this.

Each has its own unique uses and it is appropriate for different form of network interconnection. The type of device that is available for network interconnection can be divided into the following general categories
  1. Bridges
  2. Repeaters
  3. Routers
  4. Switches
  5. Connectors
 RepeatersThe repeaters is the simplest facility used for network interconnection whose major function is to receive a signal from one LAN cable segments and to re transmitting, regenerate the signal at its original strength over one or more other cable segment. A repeater operates in OSI model physical layer and its transparent to all the protocols operating in the layers above the physical layer.

A specific LAN implementation usually places a limit on the physical size of a simple cable segments. The limit is based on the physical medium and transmission technique used
Repeaters allow network to be constructed to exit the size limit of a single, physical cable segment. The number of repeaters that can be used in tandem is generally limited by a particular LAN implementation. Using a repeater between two or more LAN cable segment requires that the same physical layer protocol be used to send signal over all the cable segment




Example Two LAN cable segment is an Ethernet LAN that both used baseband transmission could be connected with a repeater. Different types of physical transmission medium can also be connected using a properly designed repeater as long as the they all handle similar type of signal.

Advantage of a repeater: It is simple in term of implementation cost
Disadvantages: Repeaters provide no method for isolating the traffic generated on one cable segment from  traffic generated by the other cable segment. When a repeater is used to connect cable segment A to segment B, whether or not there is s station on segment B that is the destination of the signal.






Internetworking Bridges The bridge is used to connect an extended Local Area Network and Bridges are more intelligent compare to repeaters. Bridges interconnect separate LAN data link rather than first cable segment. Some bridges learn the address of the stations that can be reached over each data link. They bridge (Isolate traffic) so they can selectively relay only traffic that need flows across each bridge. It operates in media Access Control. It is transparent to the protocol operating in the layers above the data link layer. A bridge interconnect network that use different transmission technique or Media Access Control Method. There are two types of bridges namely Spanning tree and source routing

Spanning Tree Bridges
They are used to form tree structure in which analogue active path connects any two stations in the extended LAN. The spanning tree bridges are transparent to ordinary station on the interconnected LANs. A spanning tree bridge learns appropriate route for friends by observing transmission that take place on the data links to which the bridge is connected. It then forwards frame over the appropriate data link when required.
 

Source Routing BridgesThey are typically used with token ring LAN, more than one path through source routing bridges can interconnect to any LAN station. The only difference is that each station is expected to know the route over which to send its frame. If a station does not know the route or if a previously known route is no longer active the station broadcast route discovery frames over the extended LAN and then determines from the responses the appropriate route to use



Routers
Computer routers provide the ability to route messages from one system to another where these may be multiple path between them. A router performs its function in OSI model network layer. Router can be use for traffic isolation, routing function, create subnets

Switches
in addition to repeaters, bridges and routers a variety of different types of switching facility can be use in constructing internet. The main purpose of interconnecting LAN data link segment is to allow a greater degree of sharing of common communication medium. Network interconnection devices allow a larger number of different network devices to be attached to the same LAN. All system attached to a LAN or extended LAN created using repeaters and bridges share the same physical transmission. Switching devices are devices designed for the opposite purpose of repeaters and bridges. In some cases when the number of devices attached to the same common transmission medium get too large, the transmission capacity can be exceeded especially when system are transmitting large quantity of data between them. One of the ideas of routers is to allow network segment to be interconnected also isolate one physical group of system from another


 

Did You Know that Technology is Causing Repetitive Stress Injury

Technology has become part and parcel of our lives be it at work or home, it’s a tool to achieve certain tasks and as a result it’s being sued repetitively. As a routine we do develop either good habits or bad habits when using technological gadget whether good or bad we’re are still faced with unknown health challenges.

What is Repetitive Stress Injury
Can be defined as a disorder or a health challenge caused by exerting too much stress or pressure on our joints, in most cases RSI will vary in type and severity so scratching your airtime card everyday may put pressure on your ankle unknowingly. Now that we have a clue of what a RSI is let’s look at some of the technological causes:-

Addiction to video games
Video gaming has become a big industry with majority of user being the youths; they spend much of their time playing game s regardless of the health challenges poses by their sitting posture, Desktop Computer monitors among others. Sitting posture is one of the major causes of RSI and may lead to further health complication. Use of keyboards in a posture that causes press on our ankle will lead to Repetitive Stress Injury. To avoid RSI while playing videos we are advice to use appropriate designed Computer chairs, use mouse pad and if you can’t afford then improvised one







Other habits that can causes RSI
Many users may not realized that while using a Computer in front of you and looking at the screen sideway you are increasing changes of developing RSI, it’s advisable to look straight into the screen with your head in a stable posture, other habits that may contribute to viewing the Computer screen from the sideways are Laptop usage while sleeping on the floor or the bed.
Texting messages may seem to be a simple task but done repeatedly in the same posture may cause RSI, playing musical instruments may also lead to RSI and all depend on how you’re sitting or standing position is.

Now that you have a clue to what RSI, it’s upon you to ensure that you take the necessary precaution while using technological gadgets not to develop RSI, and always monitor how your Kids use Computers, sitting posture and time interval spend on Computer playing games or while typing. It’s look simple but could cause a major complication to your body, it can cause swelling on the lump among other parts of the joints.  

Thursday, February 4, 2016

Computer history and generations

History of computer
Computer definition - Is a programmable machine which responds to a specific set of instructions and pre – records list of instructions which are known as programmes?

Computer History and Generations
Abacus computers - These were the first computers cable of only doing addition and subtraction
Pascaline - This was a mathematical calculator which performs addition and subtraction

G.W Leinbiz - Stepped up performance and uses punch card for storage of information, they had got additional function besides addition and subtraction, and also performs square root functionality
Charles Babbage - Uses engine and could compute data and store data and information. They were analytical machine which works as the present computers

First Generation Computers
Computer 1st generation was in the 1940s and since then a service of radical break -through of electronic design has occurred with each major break-through of computer based upon the older form of electronic design being replaced by a new form and this is called computer generations. The 1st generation of computer was these computers whose architecture was based on massive electronic valve (vacuum tube). e.g. electronically digital vacuum computers, universal vacuum computer UNVAC
Other characteristics of 1st generation Computers 1946 - 1959
•    These computers uses vacuum tube for data processing and storage
•    They had a memory size of 20bytes speed of 5mbps
•    They produced a lot of heat
•    These computers were unreliable and could not work fast with a lot of data.
•    They uses punch card for data storage
•    The programmer were machine dependent
•    First generation consume a lot of power

Second Generation of Computer -
2nd Generation computers were more reliable and faster in performance (read and write operations) than the 1st generation which was massive, instead of valves simple transistors were used in design e.g. ATLAS computers
Characteristics of 2nd generation computers 1959-1964
•    Were capable of translating, process and store data
•    Had got memory size of 32bytes speed of 10mbps
•    Were reliable compared to first generation computers
•    Produced less heat compared to first generation computers
•    They uses punch card for data storage
•    Consumed less energy compared to first generation computers

Third generation Computers
Were more powerful, reliable and more compatible in which simple integrated circuits were introduced. They emerged in early 1960s, and examples are IBM 360 Series
Other characteristics of third generation 1965 - 1975
•    They used integrated circuit(i.c.) to store data
•    The integrated circuit consisted of many transistors
•    Uses storage disk for data storage e.g. magnetic disks, tapes
•    Third generation computers were more reliable compared to other previous generations
•    They produced less heat

Fourth Generation Computers
These are computers in use today; they use sophisticated micro-electronic devices
•    These computers uses micro processors to process data
•    The micro processors are single chip which perform computer operation
•    Programs are machine independent
•    Were more reliable

Examples includes personal computers

Fifth generation computers
These are predictions that by early 21st century computers will have developed that will be able to converse with people, human communication. With the fifth generation there will be artificial intelligent computers. For more resources on Computer click Computer Resources

Classification of Computer Networks

1.    Peer to Peer and
2.    Client Server Based

Peer to Peer Networks

Has go the following characteristics
•    
They have no dedicated server to perform any routine work
•    No network operating system that uses a server or client
•    They comprise of less than 10 computers as many provide poor data sharing mode
•    Sharing of resources is not centrally controlled and depends on the users themselves
•    Can also be described as chaotic as there is no central management of resources and administrator
•    Each Computer in a peer to peer has enough resources to be shared in the network
•    There is no dedicated server or hierarchy among all the desktops
•    All the nodes are equal and known as servers
•    Normally each computer functions as a client or a server
•    They are very cheap to established, since they are relatively simple because each functions as both a client and a server and therefore there is no need for a powerful central server

Where to Established Peer to Peer Networks
•    The peer to peer is appropriate where there are ten or less users available
•    Where security is not an issue
•    Where users are located in the same Local Area Network
•    Where the organization will have limited growth within the foreseeable future

Factors to consider when implementing Peer to Peer
1.    Administration
The administration has the following tasks;
•    Managing users and security
•    Setting of resource sharing policies
•    Managing application and data and also sharing of resources
•    Installing and upgrading application
1.    Sharing of resources:  In a Peer to Peer Network users share their resources in any manner they
2.    Server requirement: Each computer must use a large percentage of resources to support the local users and use additional resources to support each remote user accessing his resources
3.    Security: Security consists of users setting a password on a resource such as a dictionary that is shared on the network.  All peer to peer users set their own security and share can exist on any node or system rather than the central server
4.    Training: Because any computer is a peer to peer environment can act as both a client and a server, users will have to be trained before they are able to perform these functions properly as both users and administrators

 

Characteristics of Computer



We have so many machines in the market with different characteristics. Computers Characteristics vary and may depend on their functions and types. There are so many factors to consider while basing your features; some may be based on manufacture design among others. They are broadly characterized by following features. 

Speed
Speed is one of the characteristics/feature that one has to look at. A powerful and high performing desktop or any other brand is capable of performing about 3 to 4 million simple arithmetic operations per second. Unit of speed is measured in nanosecond (109) and even in picoseconds (102). Speed of processing data varies and depends on various components including processor speed, memory capacity to handle data

Accuracy
The accuracy should be consistently high and the degree of accuracy of a particular Computer depends upon its design. Accuracy may depend on both application and programming software. Other than accuracy on programs, Users also play a great role to ensure that what they feed into the Computer is not junk. As in application software name Microsoft Word, the acronym called (WYSIWYG) What You See Is What You Get, depend on whatever you key in your  program, and they will never correct any mistake or error done by Human beings





Versatility
It is capable of performing almost any task provided that the task can be reduced to a series of logical steps. There are some Computers that will require additional aid to perform these tasks while others would be able to perform these tasks without additional help

Storage capacity
Different Computers comes with different storage capacity, ranging from 20GB to many hundreds GB, the bigger the storage space the more data it will handle. Having a larger storage space also help increase the speed of programs installed

Memory Size
The bigger the size the higher the speed, some programs will require high memory capacity to perform faster, with others slowing the speed if the memory capacity is too small. There are so many characteristics that you can check including the design, casing and the type of motherboard these Computers are using

Wednesday, February 3, 2016

Characteristics of Computer motherboards Form Factors

Computer Motherboard Form Factors There are many different types of Computer motherboards system that one needs to know. Below are some types of Computer motherboard form factors and their characteristics Computer Motherboard form factor: 8080 This motherboard form factors has got the following characteristics that you need to know • It is a 8 bit data bus width • This motherboard factor is a 8 bit address bus with • The computer motherboard system has a speed of 2MHZ • The computer mother has 6000 transistors • The motherboard form factors is used only in the appliances Computer Motherboard 8086 • The motherboard is a 16 data bus width • The 8086 motherboard form factor is a 20 bits address bus width • The speed of the motherboard form factor is 5-10MHz • The motherboard form factor has 29000 transistors • The internal bus ran at 8 bits Computer motherboard 80286 • It is a 16 bit data bus motherboard • The form factor is a 25 bit address bus • The motherboard has a speed of 8.12MHz • This is the first computer motherboard to use PGA • The motherboard has 134000 transistors Computer 80386DDC motherboard form factor • This is a 32 bit data bus • The form factor is a 32 bit address bus • Has got a speed of 16-33MHz • The motherboard has got 257,000 Transistors 80388SX Motherboard form factor • This is a 32 bit data bus • It is a 24 bit address bus • Has got a speed of 16-20MHz • With up to 270, transistors Those are some of the characteristics of computer motherboard form factors, below are some related and helpful computer hubs to follow

Causes of Ethical Issues in Computing Technology

Modern world if faced with a lot of challenges due to emerging technologies, as a result compromised on Technological usage is on the rise. There are so many factors why there is ethical issues related to information namely Increasing in Computer Accessibility The ratio of Computer to man in developing country is said to be improving and as a result most people are able to access computing facilities, many users from different backgrounds are capable of using Computer either for personal use or work related, but for ethical issues arising mostly from personal users whom under no supervision will do all manner of things including hacking, computer crime among others. Storage cost Decline Many people have access to storage medium where malicious programs are being saved and then propagated in many cyber networks, unlike before where only a few could purchase these storage devices for organizational use or for any personal work. Internet and Network Accessibility Network and internet have become so advanced that malicious users takes advantage while using these facilities, some are responsible while using internet and organization networks while some simply doesn’t care at all. We are always advised that when using Computers and related technological equipment either at an individual or organizational the society and individual must observed the following Responsibility Use technological equipment in a responsible manner, taking into account that any information or product arising from your activity you’re solely responsible, use a Computer in a manner that it doesn’t harm others and you can refer to the ten commandment of computing. Accountability A user will be held accountable be it at the personal level or organization level for the use of technological equipment; you should be able to account for your action and not blaming others. Liability Any misuse of Computer technology you will be liable for prosecution, whenever using a Computer remember that there are laws and regulation either by the organization or the government governing the use of Computers and related devices. Due Process Always follow due process set by organization whenever using Computers, organization have set of rules that we need to follow while accessing Computer.

How to Solve Laptop Lights Flashing Without Spending Cash

Laptop light flashing is a beep code indicating that a basic function of a Laptop is unable to start. These basic functions including and not limited to memory reading, video displaying, reading information from the hard drive among others. There are several causes of Laptop light flashing and are of different nature depending on the Laptop being used but the most common problems are associated with memory and heat related failures arising from the build up of dust in Laptop critical cooling areas. As a user you need to know how to handle your Laptop when experiencing Laptop light flashing, and before you call your technician check the following areas. Dust Removal from cooling areas This step is necessary for an old Laptop that may have accumulated too much dust, new Laptops may not have much dust and hence it isn't necessary to check for accumulated dust. Cooling areas are found at the back of your Laptop next to ports, with time Laptops collect dust on the cooling vents, as dust accumulates blocking airflow causing sensitive components to overheat resulting into Laptop light flashing. Use a dust blower to remove dust on the sensitive components. It’s advisable to wear eye and nose protective gear when removing the dust. After dust removal restarts your laptop to check if the problem still persists. Carry out a power reset if the above solution failed and you are still experiencing Laptop light flashing, and to carry out power reset the following have to be done. Remove or disconnect all Computer peripheral devices such as media cards, printers, scanner and storage devices connected to the Laptop, disconnect the Laptop AC power adapter and remove the laptop battery. Once the battery is removed, press and hold the Power button for at least 20 seconds. Without inserting battery back to its slot reconnect the AC power adapter and turn on the power button. After this process is finished and your Laptop starts normally then you have solved the problem. The other problem causing Laptop light flashing is the use of counterfeit charge, check and replaces your battery charger with a genuine one purchased from authorized vendors, counterfeit chargers extremely over heat causing multiple problems to various Laptop components leading to light flashing. The simplest faster solution is to disconnect Laptop from electrical source allowing the Computer and the battery to cool down to a good temperature preferable a room temperature and then connect back the Laptop to a power source to charge the battery again. If all these instructions are followed the battery flashing problem will be solved and the above resolution methods failed, it’s advisable to return your Laptop to the vendor for further check up or replacement. To avoid this problem recurring in the future always keep your Laptop battery away from dusty Computer desk, liquid or any unwanted materials that can cause blockage to air circulation. Perform routine cleanliness of the laptop by blowing dust from the vents and any other opening that can accumulate unwanted particles.

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