Bar codes come in many shapes and sizes. Common 1-Dimensional bar codes use lines of black on a white background to encode data. Postnet, which is used by the U.S. Postal Service, uses bar height to encode data instead. Most U.S. state drivers licenses use a 2-Dimensional bar code like PDF-417 to enable them to encode lots of data in limited space. Special 2-D bar code scanners are required to read 2-D bar codes. The coding formats vary from simple to complex. Some bar code standards also print the encoded Read More

The 301 redirect is an efficient means of webpage redirection, to be used when you have redesigned your website. This HTTP code stands for 'moved permanently'. The 301 redirect can be implemented by creating a .htaccess file in Apache servers. The process to create 301 redirects depends on the web server being used. The Meaning of .htaccess File In Apache web servers, a check is done in a .htaccess file each time a visitor or spider sends across a request for a web page. This file has instructions directed at Read More

Ethernet at the Data Link Layer Ethernet provides services corresponding to Layers 1 and 2 of the OSI reference model, and IEEE 802.3 specifies the physical layer (Layer 1) and the channel-access portion of the Data Link (Layer 2). In addition, IEEE 802.3 does not define a logical link control protocol but does not specify several different physical layers, whereas Ethernet defines only one. Ethernet Addressing Every network device has a unique physical identity that is assigned by the manufacturing vendor is called MAC address or Ethernet address. The mac Read More

Satellite receivers come in standard, HD tuners, DVR, or FTA formats. In a standard receiver, the digital broadcast signal is decoded and presented in the television in an analog format. Most satellite receivers feature an Electronic Program Guide (EPG), which contains a list of the available channels and programming. HD Receivers Made for high-definition satellites signals, an HD receiver presents these signals to high-definition televisions (HDTVs) or HD-ready televisions in their default widescreen digital format. It can also broadcast audio signals in Dolby Digital format, aside from high-definition signal and Read More

SMS and NTFS Security Overview The SMS site server must be installed on an NTFS partition. This ensures that NTFS permissions secure the SMS file structure from access by unauthorized users. By default, administrators have Full Control permission. Standard users who are not administrators have the either the Change permission, or the Read permission, or no permissions. Each SMS site system role enforces security for the SMS components and for user access. With regard to directories and shares, for all site system roles other than the client access point and Read More

The Session Layer is Layer 5 of the OSI (Open Systems Interconnection) Model of computer networking. The Session Layer is directly after the Transport Layer and before the Presentation Layer, allowing it to interact with applications as well as network components. The Session Layer is responsible for opening, maintaining, and closing all sessions between multiple applications and/or devices. Because almost all network-related events involve the use of sessions, the Session Layer is used extremely often.   How The Session Layer Works The Session Layer is responsible for opening, maintaining, and Read More

A projector is able to accomplish a projection with the help of a combination of lenses along with the other technical things. A Fresnel lens projector is one which has different Fresnel lenses placed in the projector. Fresnel Lens Fresnel lens was invented by a French physicist, Augustin-Jean Fresnel. These lenses have a large aperture and a short focal length. They are very thin and are lighter in weight allowing more light to pass through. Thus, are used in the objects where bulky lenses are prohibited. An Overhead projector (OHP) Read More

  Although connecting a laptop to a projector is simple, without proper preparation, the projector connection can fail, resulting in a delayed or cancelled presentation. The most common way to connect a laptop to a projector is via VGA cable, with SVGA and S-Video cables providing alternative means of making the connection. A common task that arises for students and business personnel is connecting a computer to a display projector to show a presentation to a group of people. How to Connect a Laptop to Projector Step 1 – Identify Read More

Over the last decade, millions of people have kept more and more personal information on their computers. From credit card numbers to sensitive emails and word documents, a vast amount of personal files are on almost any home computer. While keeping personal and sensitive information on a home computer is relatively safe, if you plan on throwing out your computer, selling it, or even selling just the hard drive, you may be allowing others easy access to all your personal files. Here are some tips on how to remove these Read More

A floppy disk is a media storage device that has been used in computers since the mid-1970s. Modern floppy disks measure 3 ½ inches diagonally and are both read and written to by a Floppy Disk Drive (FDD). While floppy disks are rarely used by modern computers and have had little to no motherboard support as of 2010, they are still used for some applications and can be accessed via external USB devices.   How To Format A Floppy Disk In order to format a floppy disk, or erase its Read More