Specialized Computing Blog

Need to become CompTIA Network+ Certified? Join certified instructor Bill Ferguson in Virtual Training Company’s CompTIA Network+ Certification tutorial as he shows you everything you need to know to take and pass the test. He begins by introducing you to the OSI (Open Systems Interconnect) model, then explains how network adapters allow computers to communicate, the relation between the topologies and technologies of networks, and how to control network traffic. Other topics he covers include remote connectivity, tools used for troubleshooting both hardware and software, and how to protect your network with Firewalls. Learn all you need to know for CompTIA Network+ Certification now by simply click one of the topics below.

Introduction and Overview

Overview Part 1

Overview Part 2

The OSI Model

What is the OSI Model?

The layers of the model

Network Adapters

Network Adapter Overview

Properties of Network Adapter Cards

Configuring a Network Adapters Resources

Configuring a Network Adapters Addressing

Troubleshooting Network Adapters

Network Cabling Communication

Network Cabling and Communication Overview

LANs vs. WANs

Communication Methods

Twisted Pair Cabling and Connectors

Coaxial Cable

Fiber Optic Cable

Topologies and Technologies

Types of Topologies

The Bus Topology

The Star Topology

The Ring Topology

The Mesh Topology

Hyid Topologies

Types of Technologies

CSMA/CD Access Method

Token Ring & Token Passing

Fiber Distributed Data Interface

Network Hardware

Network Hardware Overview

Bridges

Routers

Brouters

Switches

Remote Connectivity

Remote Connectivity Overview

Remote Communication Layers

Modems

Modem Standards and Features

Remote Connectivity Terminology

Flow Control and UART Protocols

Installing Modems

Troubleshooting Modems

Creating Dial-Up Connections

Troubleshooting Hardware

Environmental Conditions

Physical Layout

Common Network Tools

Troubleshooting Tips

Protocols

Network Protocols Defined

Access Protocols

Transport Protocols

TCP/IP

Overview

The Evolution of TCP/IP

TCP/IP Fundamentals

The TCP/IP Suite

The TCP/IP Suite continued

The TCP/IP Suite continued

Ports and Sockets

IP Addressing

IP Address Classes

Binary Numbers

Default Subnet Masks

Anding IP Addresses

IP Address Configuration

Subnetting and Routing

Routing Tables and Routing Protocols

Name Resolution

Name Resolution Overview

Host Name Resolution

NetBIOS Name Resolution

Name Resolution Steps

Firewalls and Proxies

Firewalls and Proxies

Firewalls

Proxy Servers

TCP/IP Tools

Tools from Command Prompt

Ping

TraceRT

Remote Access Protocols

Remote Access Protocol Overview

SLIP vs. PPP

PPTP vs. L2TP

Network Operating Systems

The Role of an NOS

Components of a Network

Types of Networks

Network Clients

Directory Services

Directory Services Overview

NT Trusts

NT Domain Models

NT Domain Controllers

Active Directory

Accessing Resources Through a Network

Share Permissions

NTFS Permissions

Sharing and Mapping Drives

UNC Command

Sharing Printer

Optimizing a Network

Tools for Networks

Event Viewer

Task Manager

System Monitor

Network Monitor

Troubleshooting & Ongoing Maintenance

Fault Tolerance

Fault Tolerance Defined

RAID

Backup

UPSs

Ongoing Network Maintenance

Patches and Service Packs

Virus Protection

Taking the CompTIA Network+ Test

Tips on Taking the CompTIA Network+ Test

The new Apple iPad has gotten a ton of hype leading up to the release of it. Is it as good as the company claims? Will it really bring about the death of laptops, as many believe? Here are eight of its notable features, to help you decide for yourself:

#1) Long-lasting battery

The company says the average lifespan for the battery is about ten hours. However, many people say it’s really longer than that. Some claim you can get it to go eleven hours or more.

This will save you a lot of money if you use mobile devices often. This enables you to watch five two-hour long movies before needing a replacement.

#2) Speakers

The quality of the sound is pretty good, even when turned up loud. Many were worrying the sound clarity would be subpar like a lot of mobile devices, but this really isn’t the case.

It’s not as crystal clear as a quality television. However, when considering the size of the iPad, it’s pretty decent.

#3) Screen width

The screen is 9.5 inches wide, which is quite large when compared with other mobile machines. While it’s obviously not as big as a laptop, 9.5 inches is easily big enough that you won’t have to strain you eyes when watching the screen contents.

It’s even sufficient for more than one person to comfortably view it at the same time. So if you have friends that want to see a movie, you are in luck.

#4) Cool temperature

If you are familiar with Apple laptops, you probably dread holding them on your lap for a long time. As the system heats up, they tend to become extremely warm, which makes holding them very uncomfortable. However, the iPad stays cool even after hours of use.

#5) Third party applications

The iPad can use third party applications without needing the use of modifications. In other words, it’s more adaptable than many expected.

#6) Storage space

Even the least expensive iPads contain sixteen gigs of room. This is more than anticipated.

#7) Tiny size

It’s very easy to carry around, weighing in at one and a half pounds. So you can easily carry it in your pocket without it being a burden.

#8) Built-in dictionary

The iBooks application has a dictionary that provides fast explanations of words when browsing the net. And it’s also capable of finding specific words within e-Books, which is a rather advanced feature.

The bottom line is, the iPad does have some neat features and it’s shaping up well. It may not be time to throw out your other mobile devices yet, but that time just moved a few steps closer.

Today, there are more forms of memory than you can shake a stick at. Technically, memory can be anything used to store data, but today it is most commonly referred to as quickly accessed forms of storage. Just think about how slow your computer would be if it had to access the hard drive every time it needed to process a command. For this very reason, the computer selects a temporary memory device to store all of the commonly used commands so they can be pulled back up quickly. The different types of quick-pull memory include flash memory and various types of random access memory and read only memory. Let’s take a look at these different types of memory and see what sets them apart from each other.

Read Only Memory

ROM is a type of memory where information has been pre-recorded and is only available to be read. There is a slight variation, called PROM, or programmable read only memory, which is a set of memory devices, like a read only CD, that can be programmed, but then never changed. Once the memory is on the device and the session is closed, the memory cannot be added to or changed.

Random Access Memory

While read only memory can be accessed in a certain order, like a cassette tape, random access memory can be accessed from any point at any time, as long as you know the exact location of the cell the memory is stored in. Most of a computers’ quick access memory is stored in RAM, but there is an issue when the computer looses power; the memory is erased.

Flash Memory

Finally, the most notable type of memory today is flash memory. This memory comes in the form of flash drives, also known as thumb drives, and even the cards you insert into your digital camera. Flash memory is considered non-volatile, which means that it can be electronically erased and reprogrammed when deemed necessary. Today, each flash drive can be erased in pieces and parts, whereas, five years ago, if you wanted to erase a portion of data on the flash drive, the entire drive had to be wiped clean.

Flash memory is also more cost-effective than any other type of memory produced today. There are currently developments being tested in hopes of making hard drives only from flash memory. The reason this is the wave of the future, there are no moving parts in flash memory. No moving parts mean that there will be far fewer failures with the memory.

Conclusion

There are numerous types of memory. Each type has a certain purpose for which it was made. Computer memory is a basic storage device, just like your brain. The only difference between your memory and a computer’s memory is the way in which the information is recovered and the space available to store information. The next time you try to do something on an electronic device, see if you can identify what type of memory is being used.

Virtualization

People were practicing virtualization long before computers. Architects were drawing buildings, contractors were making detailed sketches and engineers were developing their systems; all with a pen and paper. Today, we can do far more than the simple 2-D drawings of the past. Virtualization allows us to build complete cities, in high detail 3-D imagery, then with a click of the mouse, decimate and rebuild in a completely different manner. Not to mention, virtualization is starting to become a mega-trend in the health industry. Doctors and health care professionals are able to create life-like replicas of situations and see the possible side effects and outcomes of different procedures.

In the computer world, virtualization has the same connotation, but with different aspects. For instance, instead of mapping out cities or hearts, Information Technology workers are creating virtual workstations, servers, operating systems and network resources.

Computer virtualization allows you to have a network of computers, running two or more completely different environments, on a single piece of hardware. For example, Apple can run their standard Operating System (OS), while having the ability to mimic a Dell PC and run the Windows OS. Virtualization splits computers from their applications, by creating a virtual machine (VM), which gives it the ability to act as a host to a larger number of systems.

There are a wide variety of virtual specialties, including Operating Systems, network, server, hardware and even storage. Let’s take a look at what each discipline entails.

Hardware Virtualization

You probably know a little about virtualization if you have ever decided to partition your hard drive into logical divisions, creating basically two hard drives in one. This is hardware virtualization. This discipline is tasked with partitioning the computer’s memory into separate and isolated virtual machines to simulate multiple machines within one physical computer.

Operating System Virtualization

This type of virtualization allows the computer to take a step back and act as a simple display for different operating systems; much like Apple started doing a few years ago. This uses software to allow a piece of hardware, such as a computer, to display different operating system windows at the same time because it is not tied to either of the two systems.

Network Virtualization

Network virtualization combines all of the available resources in a network by splitting up the available bandwidth into channels. Each of these channels is completely independent of each other and can be devoted, or reassigned, to a particular server or individual in real time. This allows the complex network to be separated into manageable parts that can be worked on or devoted to different tasks without affecting the other ones.

Storage Virtualization

This type of virtualization pools physical storage locations from multiple devices within a network and allows it to act as a single storage device. If you have a single drive to save all of your documents where you work, this would be an example of storage virtualization.

Server Virtualization

Bandwidth is a large issue for companies; a hot commodity within the IT world of corporations. Server virtualization hides the identity of each user from the physical server and keeps users from having to understand and manage the ever-daunting task of server resources. It also increases the ability to share resources and gives the company the ability to expand in the future.

Conclusion

While we have been working with virtualization before the digital age, the technology we have access to now changes the entire game. These categories of virtualization can actually lead the way into autonomic computing; where IT teams will be able to manage the systems based on perceived activity and resources used, allowing clients to only pay as resources are needed.

Next week, we’ll look more in-depth at computer networking…

The password for the various protected internet/computer accounts is a set of characters, in a specific sequence and case sensitive. Together with the unique user name or ID, the password confirms that the user or person trying to access the account is the real one. The user name or ID is normally displayed or shown in the log in box or in the pages of the account but the password is supposed to be known only to the account user or owner and the system that runs the account. The minimum and maximum number of characters in a password depends also on the system set and it normally consists of letters in upper or lower cases, numbers and other characters.
As the password is entered, it appears only as asterisks in the space provided so that its secrecy is maintained.

The internet has really changed the ways things are done. Very important and secure transactions, like payments for purchases, banking as well as  safekeeping  and transfer of sensitive documents and other files are processed online. With the increase in online transactions, so are the number of cyber thieves who have developed techniques to crack the passwords. Most of the time, the account owner is to blame because the password isn’t strong enough to ward off  ‘hackers” trying to break it.

Choosing the Best Password

How do you choose the best password that is strong enough to withstand any attempts to access the account? Here are some tips in creating passwords:

1. Don’t use a password that is in the dictionary, even the foreign ones. There are password cracking software to determine the exact word in seconds.

2. Don’t use passwords that are associated to you like your maiden name, place of birth, Social Security number, children’s names,  phone numbers. Mix upper and lower case letters with numbers and other symbols allowed by the system like  “miG67Ped.” This would take a long time to guess and the “hacker” will most likely just leave and go to the next target. However, the account owner should make sure there is a way to remember the password. One way is to associate the words and numbers with easy-to-remember words, dates or names. The password could also be saved on a CD or USB and copied to the log in form. Keep any password record offline.

3. Don’t use a password that is used on your other accounts.

4. Don’t use commonly used passwords like ” 12345678″ or “password”

The password is like the secret key to a secured internet/computer account. Make sure it can really secure the account.

There are times when we type things on our computer and save them on our computers yet we don’t wish people to read whatever it is we have written and saved. For those who don’t know how to protect what they have written from people who might have access to their computers other than themselves, using a password protected system to keep your documents from being accessed by other people is one thing that should be learned.

Create a Password For Your PC

One of the easiest ways for you to protect your documents from other people who might use your computer from time to time would be to create a password for your User profile. Your User profile can be locked so that only you can access it and other people can use the PC from another profile that can be for common use. To password protect your User profile:

1.    You should first click on start then on settings and finally on Control Panel.
2.    From control Panel, access the User Accounts and click on your User account.
3.    Follow the steps for creating a password for your user account and apply it.

Create a Password for Your Word Documents

After you create a certain document you want to keep away the eyes of people you don’t want to read it, you can always password protect it after you write it. This kind of a move password protects individual documents that you feel should be hidden from everyone else without having to create a separate user profile on your computer. Here are the steps you can use to do this:

1.    You first choose options from the tools menu.
2.    You then click on the security tab on the pop-up and you type in the password that is needed to open the document in the box provided for.
3.    You will then click on OK after typing in your password and you will need to re-verify this password after you click OK.
4.    You can then safely save the document and be secure that no one can read it without the password. You can only open this particular document after you provide the password.

Protecting your documents with the use of either a user profile password or a specific document password will help ensure that whatever you wish to keep to yourself will remain safely away from people you don’t want seeing your documents and what they contain.

Buying an iPhone could be one of the most fun (and productive) decisions you ever make. After all, with the economic crisis affecting everyone, deliberating on the pros and cons before buying an expensive device like iPhone shouldn’t be taken lightly.

Here are 5 iPhone buying guides that will help you make that important, well-informed decision. After all, you don’t want to waste your hard-earned money for something that won’t satisfy your needs.

Where to shop

With the iPhone popularity at its peak, many people find it hard to buy an iPhone. Some say they have to line up at Apple stores and wait too long for their turn. If you can’t handle the stress of lining up just to get buy an iPhone, you can dash to the nearest AT&T/Cingular store. This could be a good chance for you since not so many people are aware that this particular store will be selling iPhone units too.

If you think that there is no way for you to get through the long line in Apple store or in AT&T store or if you are just too lazy to get out and stand in the crowd just to get the coolest thing in town, you can still settle for online shopping and enjoy the privileges and ease that your credit card and to-your-door shipping provide.

However, considering convenience and all, it is still practical to buy your iPhone at Apple stores because the staff can readily give you an alternative store if ever their stocks run at out. Moreover, Apple stores provide detailed workshops that will teach you how to make the most out of your iPhone.

Check Your Budget

So before buying an iPhone, look at your budget first and stick to it. If you think you can squeeze in an extra $499 for a 4GB iPhone, dash to the nearest Apple store immediately. If not, stay cool, keep calm, and hold on to your resources. You may never know it might be worth waiting for the right time.

Know What You’re Getting

Some critics say that the iPhone might have been over hyped and buying without knowing everything about this gadget might only send you tons of disappointments. So before making a mad dash out there, try to research for more information.

Lastly, relax. It is just one of those here today, gone tomorrow items. If you really don’t need one, don’t buy.

With the rising prices of commodities, it is only natural to be more careful with every penny spent. This is especially true for purchases that aren’t a priority, such as accessories for your new iPhone. Since you may have already spent hundreds for your new gadget, it is wise to find cheaper prices for your phone’s accessories.

One auction shop that will surely provide you with reasonable prices for iPhone accessories, or even the mobile unit itself, is eBay, an online auction site that is open for anyone who has access to the World Wide Web. However, when conducting dealings with sellers on eBay, you need to be very careful. Below are some of the things you should remember when buying iPhone accessories on eBay.

Know the market price

If you plan to bid on eBay auctions, the first thing you need to do is to check the market prices of the accessory that you are planning to buy. It would be futile to buy at an auction if the price you are going to pay is higher than the cost of just purchasing the accessory at your local store. Since shipping prices aren’t included in the selling price, you should always take in consideration the total cost, shipping plus the price of the accessory, when comparing the cost of buying on eBay with that of the local store.

Check Seller’s Background

You should always check the background of the seller before dealing with him or her. Unfortunately, there are unscrupulous individuals on the Internet so you need to be careful. You should look at the seller’s ratings and the feedback given by his or her previous customers. If there have been many negative feedback comments left about the seller, then it would be wise not to deal with him or her anymore, no matter how attractive the seller’s offer may seem.

Check for authenticity

If you are buying an iPhone charger, USB adapter, cables, docks and other accessories that will affect the mobile phone’s performance, it is best to check if the accessories sold are authentic or genuine Apple iPhone gadgets. There may be some sellers who don’t specify whether what they are selling are original because the accessories may be reproductions. Always remember that you have the right to know the quality of the things you are planning to buy.

Be sure to follow the tips above for a hassle free shopping of iPhone accessories on eBay.

Whether you are choosing a new video card to come with a new computer, or whether you are buying a new card to upgrade an old system, it helps to know a bit about them to help guide you towards what you need.

What is a video card? It is the component responsible for the pictures that you see on the computer screen. Every computer these days comes with a video card, but a good video card is essential for gamers, graphic artists and those who watch TV on their computers. Before getting just the basic video card or the top of the line one, know how to shop for one.

There are many accessories mentioned when you buy a computer. The sales associate may ask about what you plan to do with the computer to help you determine the type of video card you will require.

A video card has three basic criteria for choosing one.

• Price
• Speed
• Resolution

Video Card vs Graphics Card

You may hear people talk about video cards and graphics cards. They are similar in what they do. Video cards are more useful to gamers. A gamer wants to have the greatest amount of memory on their video card so that they can play faster. Certain games take up a lot of space and no one wants to have technical difficulties just as they are about to slay the giant beast.

Video games have advanced beyond the huge rectangular blip that was the ball in the Atari table tennis game. Resolution is important but some gaming worlds are so advanced that faster play is more of the essence.

Graphics cards are desired more by graphic artists and those using CAD. Here, attention to detail is essential in your designs so that is what will be the main consideration here. The same goes for the casual user who surfs the Web.

Price

Video cards range from moderately expensive to quite expensive. A website surfer won’t want to spend hundreds of dollars on a video card, but a graphic designer might to suit their job needs. Cheaper doesn’t mean inferior quality, just fewer bells and whistles. That’s okay if you are not into gaming or computer design.

Not sure what all the letters mean? Talk to someone at your local computer store who can help you choose your video card wisely.

Jump drive, flash drive or thumb drive – they are all similar names for the same kind of device. These are external drives that are used to save information that you want to keep. But, how many of them do you really need?

Your computer has a hard drive. And, that hard drive has a certain amount of memory on it.

A flash drive is another form of storage device which is extremely portable (usually about the size of a keychain). They usually connect to your computer via USB ports and can range from 256MB to several gigabytes in storage capacity. You can have huge external hard drives with terabytes of data storage space, but we will concentrate on the flash drives for now.

Flash drives have several advantages. One, they are easy to take with you. You can use them anywhere you have a computer with a USB port. Your data is always available you when you need it.

Second, they are durable. You can hang them on a lanyard; place them in your purse, on a keychain or even in your pocket. Because of their size and lack of moving parts, a little jumbling is tolerated well.

Third, they can store massive amounts of data for almost instantaneous retrieval. Keep your important documents, pictures, music, videos and movies on flash drives to be used anywhere. They replace carrying around tons of folders in your briefcase or backpack.

Realistically, you only need as many flash drives as you have different tasks to use them for. For example, personal and business needs could be kept separate. You may want one to keep in your briefcase at all times with the most important work documents on it, and another to attach to your key ring with family pictures and videos on it, ready to show off Junior’s Little League debut at a moment’s notice.

Flash drives are economical and easy to use. It is easy to check to see how much memory you have on a flash drive to know if it is time for another one to be purchased. You can also purchase flash drives with some security built-in (passwords, encryption and the like) to ensure that your confidential work design files don’t end up in the wrong hands when you forget it at the airport.