Ethernet and Exabyte

Ethernet

Ethernet is the most common type of connection computers use in a LAN (local are connection). It was developed in 1976 by the Xerox Corporation in collaboration with DEC and Intel. Ethernet was introduced commercially in the 1980’s and was standardized in 1985 as the IEEE 802.3 (Institute of Electrical and Electronics Engineers project 802).

An Ethernet port resembles a regular phone jack but has slightly wider dimensions. This port can also be used to connect one computer to another computer, local network, or an external DSL or

cable modem.

Ethernet originally came in two forms, the 10BaseT and the 100BaseT, with transfer speeds of up to 10mbps and 100mbps respectively. The newer and faster “Gigabit” Ethernet connection's data transfer speeds peak at a whopping 1000mbps.

Exabyte

An Exabyte is a unit of data or information storage and is 2 to the 60th power bytes, or 1,152,921,504,606,846,976 bytes. That’s over one quintillion (1,000,000,000,000,000,000) bytes. An exabyte is 1024 petabytes and precedes the zettabyte in units of computer

storage measurement. Every piece of content ever written would take up roughly 5  exabytes.

Global computing capacity has increased at a rate of about 58% every year from 1986 to 2007. The world’s technological capacity for information storage was 2.6 exabytes in 1986, which grew rapidly to 295 exabytes in 2007. 295 exabytes is equivalent to roughly 404 billion CD-ROMs, that’s almost 61 CD-ROMs per person. Piling up 404 billion CDs would easily create a stack from the earth to the moon and still have around a quarter of the pile left over. In today’s world around 2000 exabytes of information is broadcast every day.

Encoding and Encryption

Encoding

Encoding means converting of data from one form to another. It has several types including image encoding, audio and video encoding and character encoding.

By encoding digital audio, video and image files into different, more efficient, compressed formats a lot of disk space can be saved. Encoded media files typically maintain similar quality to their original uncompressed counterparts but have comparatively smaller file sizes. A WAVE (.wav) audio file that has been converted to an MP3 (.mp3) file may be 1/10th the size of the original WAVE file. This also applies to the MPEG (.mpg) compressed video file which takes only a fraction of the disk space the original digital video (.dv) file would take.

Encoded data can only be read by a program that supports that type of encoding. This is accomplished by Codecs in the case of audio and video files, which decodes the data in real-time.

Encryption

Encryption is used to code or scramble the meaning of messages. These messages can then be decrypted only by someone who has the correct code or key, which is called a cipher. Encryptions are primarily used to secure web sites or any other means of data transfer. If a third party were to intercept a message sent via a secure connection, they would be unable to make any sense of the encrypted data.

The use of encrypted messages dates back thousands of years to the Romans, who first used substitution ciphers. The first machines to use ciphers came into use during the 1930’s. The German Enigma cipher machine which was used during World War II used multiple rotors to create a continuously varying cipher that was thought to be unbreakable. Allied code breakers succeeded in exploiting the flaws of the German machine with electro-mechanical and electronic devices, while simultaneously unknowingly advancing computing technology.

DirectX

DirectX

DirectX is a set of commands and functions that are ready-to-use and makes it easier for the programmers to create software; mainly games. By using DirectX com-

mands, developers can use predefined functions to manage video and sound of their game. Technically DirectX is a set of APIs(Application Programming Interfaces) that software developers use when creating programs on Microsoft platforms. It is used to denote all the APIs beginning with Direct, i.e Direct3D, DirectPlay, DirectMusic, DirectDraw, DirectSound and the like, with X substituted for each API. The X initial was later used by Microsoft to name its gaming console Xbox which uses the DirectX technology. DirectX was introduced with the Windows 95 Service Release 2. The purpose of DirectX was to make Windows as developer-friendly as MS-DOS.

Dynamic Host Configuration Protocol

Dynamic Host Configuration Protocol

DHCP, or Dynamic Host Configuration Protocol, is a network protocol that allows the server to dynamically assign an IP address to your computer from a defined range of numbers stored on the server. When your modem comes online, it indicates to the DHCP server that it is looking for an IP address. The server acknowledges this request and your modem transmits its MAC address to the server. The server looks up the reserved IP or assigns a new one to your system. DHCP is preferred over static IP addressing, in which a computer is configured manually to a specific IP address, in setting up large networks. Static assignment may lead to loss of service if two computers are configured with same IP address. DHCP servers typically grant IP addresses to clients for a limited time interval, and renewal of IP address is client’s responsibility before expiration of that period. 

Defragment

Defragment

When a file is stored on your computer, it is distributed across the memory, i.e it is fragmented. To access that file, the reading head of hard drive has to skip many locations to fully read its contents. Because the data is spread across the entire disk, the hard disk seek time is increased and it can reduce your computer’s performance. Defragmentation is the process to compile those fragments and store them in contiguous memory locations from start to finish. If you hear more than the usual amount of sputtering noises from your hard disk, in all likelihood it's extremely fragmented and it's time to run defragmentation. Windows comes bundled with a defragmentation program or a commercial disk utility such as Norton Utilities can also be used. Mac users can use DiskWarrior or Tech Tool Pro. Its good practice to defragment your hard disk once a month. Of course defragmentation doesn't apply to SSDs and in fact doing so will reduce their life.

Cryptography

Cryptography

Cryptography is derived from a Greek word “crypto” meaning hidden or secret, and “graphien” which means “writing”. Cryptology is the study of techniques that help us in performing secure communications through networks without allowing the information dissemination to the adversaries or any other unauthorized third party. It involves concepts

of data integrity and confidentiality and calls for strict authentication. Cryptography involves processes such as Encryption, Decryption, and

Cryptanalysis etc. Different types of cryptography include Symmetric Key encryption where both the sender and receiver share the same key and Public key Cryptography where the sender and receiver have different keys. Cryptography has always gained genuine traction from intelligence and law enforcement agencies. The crime investigation agencies have groups of cryptanalysts who are continuously involved in the decryption of un-cracked ciphers and generating new, stronger ciphers for encryption. 

Codec

Codec

Codec is a device or computer program that can encode and decode a stream of digital data or a digital signal. Originating from the pair CoderDecoder, the term Codec should not be confused with a coding format as it is a program that can read and write files as opposed to a format that is coded to and decoded from. Based on the compression quality codecs can be classified as lossy codecs where quality is reduced to achieve compression and lossless codecs where archiving is done but all the information presenting in original stream of data is retained. There are media codecs which are designed to put special emphasis on certain aspects of a media. For example, a sport video needs better motion encoding while an art exhibit video demands better encoding of color information. The Codec Engine is a set of APIs that we can use to instantiate and run relevant algorithms. Codecs normally come grouped in libraries that contain the codecs any application needs to access different audio/visual file types.

BIOS

BIOS

BIOS(Basic Input/Output System) is a program pre-installed based on Windows based computers that the microprocessor uses to start up. The BIOS is an integral part of your computer, and your CPU communicates through it to check all the hardware connections such as the hard disk, video adapter, keyboard, mouse, and printer. If all attachments are in place, it loads the operating system into the RAM. When device details change, only the BIOS program needs to be changed. It frees the operating system from worrying about the exact details of hardware attached to the system. BIOS is located in the EPROM(Erasable Programmable Read Only Memory). When the computer is switched on, the microprocessor passes control to the BIOS which is always located there. To reprogram the BIOS, the EPROM chips have to be physically removed from the motherboard. They may be erased by prolonged exposure to ultraviolet light. Modern systems use rewritable flash memory (which can be electrically erased) to store BIOS, as hardware manufacturers frequently release BIOS updates. Rewriting the contents of ROM is also called flashing. BIOS is being replaced by the more complex Extensible Firmware Interface (EFI) in many new machines.

Apple

Apple

Apple Inc, which was previously Apple Computers Inc., is an American multinational which designs, develops and produces consumer electronics, software and personal computers. Notable products include all of its products – be it the iPhone, iPad, iPod, iMac, Mac Book, MacBook Air, OSX or iOS and its corresponding applications Safari Web Browser, FaceTime and the App Store.

Apple was founded in 1976 by three ex-Atari employees with Steve Jobs as its CEO. Its first product was the Apple I computer which lacked any basic features that today’s computers have. Apple II was its first major hit; it was in fact the bread-winner for the company. Following the success, Steve Jobs pulled together a team of his own to develop Macintosh, which he envisioned to be revolutionary. It was during this time that Apple faced a lot of conflicts

(better known as “projectitis”) between its Apple II and Macintosh employees,

From 1985 to 1997, the Apple business witnessed a downturn due a to a continuous line of failed products including digicams and portable CDs. In 1985, Steve Jobs, the founder of Apple resigned as its president and went on to establish NeXt. In 1997, he returned and Apple launched the first iPhone which became a huge success. Presently, Apple is considered to be the most valuable company in the USA.

It is, however, criticized for its “designed for the dump” style by releasing a new product every 12-15 months, making the old products obsolete quickly. This leads to a lot of wastage and harm to the environment. Also, Apple is not well known for any philanthropic contributions.

Android

Android

Linux-based Android is the most widely used touchscreen-based operating system designed especially for mobiles and tablets. Android Inc. was acquired by Google Inc. in 2005 and since then has been developing and promoting the OS along with Open Handset Alliance. It released Android as open-source under the Apache license. Android is based on

Java language and apps can be developed using the Android Development Tools (ADT) plug-in. Android can also be used on other devices such as laptops, netbooks, smartbooks and smart TVs (Google TV).

Android has a huge-community of developers who develop apps that get published on Google Play and the Amazon App Store. Boom of Android development made Java the most used programming language in the world. In 2011, there are more than 500 million active devices that have Android OS, which constitutes to 75% of the mobile and tablet market share. As of Sep 2012, there are more than 675,000 apps available for Android and more than 25 billion downloads have been made from Play Store of Google Play.

Android has been criticized for aping the design of iOS exactly. But, who doesn’t Apple blame for copying its designs?

AMD

AMD

AMD (Advanced Micro Devices) is an American computer processor manufacturer and is a famous rival to the world's leading microprocessor manufacturer, Intel. AMD processors are used in HP and Toshiba laptops and desktops. It is presently the second largest manufacturer of computer processors in the world and Intel’s only significant rival in the CPU market for x86-based PCs.
AMD’s product line includes microprocessors, motherboards, chipsets, embedded processors, graphics processors for servers, personal computers and embedded systems applications. Post acquisition of ATI, AMD took a leap into graphical processing units (GPUs) by starting an initiative named “Fusion” which implies the merging of CPU and GPU on its mainstream chips. AMD and NVidia together have the whole 100% market share of GPU market space. Some notable AMD GPUs include Radeon, Eye Speed, and FirePro. AMD achieved a Guinness World Record for the "Highest frequency of a computer processor" at 8.429  GHz.
AMD’s latest technology, BullDozer had a lot of hopes riding on it due to its 8 cores, but it wasn't all that great.

Address Resolution Protocol (ARP)

Address Resolution Protocol (ARP)

ARP is an internet protocol used to map the IP networking address to the physical MAC address of a machine. This is a protocol used to resolve the address of the client machine that makes a request to know his machine address/MAC (Medium Access Control). The server machine which is on a remote computer gets a piece of information from the ARP which helps it uniquely identify the client machine. The whole process completes when the client receives a response from the server containing the required address. There are two types of ARP: Gratuitous and Proxy. Proxy ARP is more vulnerable to security threats and hence Gratuitous is used more often.

The reverse process i.e. finding the IP address can be done with the help of Reverse ARP. In this case, the client sends it physical/MAC address and then the server replies with the IP address.

Ad-hoc network

Ad-hoc network

Ad-hoc is a Local Area Network that is built spontaneously and doesn’t rely on pre-existing infrastructure such as routers, etc. Hence, all devices in an ad-hoc network have equal status on a network and participate in routing and data-forwarding. Data packets are dynamically forwarded to and from each other. It’s useful in areas where central nodes don’t exist or can’t be relied upon. This is widely used in emergency situations and military conflicts. Ad-hoc networks can be easily and quickly deployed which increases its application domain.

Two types of ad-hoc networks are possible depending upon the devices that are connected:

Heterogeneous, where each machine has different capabilities and hence performs different actions and Homogeneous, where all machines/nodes have the same capabilities and hence the same responsibility.

Three types of ad-hoc networks exist on the basis of its application:

1.            Mobile Ad-Hoc networks: A network of mobile devices.

2.            Wireless Mesh networks: A network of radio nodes in a mesh topology.

3.            Wireless Sensor networks: A network of distributed autonomous sensors to monitor physical or environmental conditions.

ActiveX

ActiveX

ActiveX is a framework developed by Microsoft for defining reusable software components, like an API. This is a programming-language independent framework and hence can be used in a wide range of applications. It was developed to simplify the complex processes of Object Linking and Embedding (technology that allows linking to documents and objects) and Component Object Modeling (used for inter-process communication). Many of Microsoft’s applications such as Internet Explorer, Office, Visual Studio and Media Player use ActiveX controls.

ActiveX helps make web browsers more interactive. Functionalities like opening PDF files within the browser can be included with the help of ActiveX controls. ActiveX controls dynamically vary depending upon the website that’s accessing them. These controls are basically like browser add-ons and hence each has different functions such as enhancing security or enhancing video content.

Since ActiveX automatically downloads itself and installs during browsing, Microsoft had to work on plenty of security issues to secure the browsing session. It recently made ActiveX an Open Source technology to encourage developers to join in.

Accelerated Graphics Port (AGP)

Accelerated Graphics Port (AGP) 

The AGP port was designed by Intel in August 1997 for video cards and 3D card accelerators. AGP is the brainchild of Ajay Bhatt, Intel's Chief I/O architect, who was also behind the invention of USB ports (Remember that Intel advert with an Indian walking around like a rockstar?!). AGP was a milestone in the area of video cards and GPUs. AGP introduced a dedicated point-to-point channel due to which the graphic controller can directly access the system memory. AGP allows 3D textures to be stored in the main memory rather than the video memory – a significant development over the PCI bus. This increases bandwidth and supports more powerful graphics.

A much advanced AGP Pro was developed later; it provided more power to video cards.

Earlier, not all operating systems and motherboards supported AGP due to limited or no driver support. By 2010, however, many motherboards were produced with the AGP slots.