How Google Search Works

Global IPTV: $19 Billion Market By 2012

The worldwide number of subscribers of IP television is expected to rise by more than 64% this year, as revenue soars by 93.5%, a market research firm said Thursday.

IPTV subscriptions will increase to 19.6 million this year from 12 million last year, and revenue will grow to $4.5 billion from $2.3 billion, respectively, Gartner predicted. At the end of the year, 1.1% of households worldwide will be IPTV subscribers.recast. Driving the increase is growing consumer demand for video, as well as the entry of new content providers.

New competitors in Internet video include portal players such as YouTube and Joost, and social network sites such as MySpace and Facebook, Gartner said. In addition, device manufacturers are offering their own Internet-based offerings, such as NeuLion and AppleTV, while some broadcasters, such as the BBC, NBC, and Fox, are taking their programming directly to consumers.

On the distribution side, Internet companies, such as Amazon (NSDQ: AMZN).com and VuDu, are offering video on demand, as well as video rental services, such as Netflix (NSDQ: NFLX) and Blockbuster. Such companies are developing or have developed a combined set-top box and video download service.

While the number of IPTV subscriptions is increasing, there are vast regional differences. Western Europe has the largest number of IPTV subscribers, but North America is the largest market for IPTV revenue, Gartner said. IPTV revenue in North America is forecast to reach $2 billion in 2008, and grow to $8 billion in 2012.

"Before 2008, the IPTV operators' emphasis had been to spread their footprint and effectively provide a 'me too' solution to cable and satellite," Gartner analyst Elroy Jopling said in a statement. "In the future, especially in the developed markets, we will see an emphasis on innovation and differentiated pay-TV services."

Gartner defines IPTV as the use of a carrier-based managed IP broadband network to deliver TV and video to the end user through a set-top box. The picture quality must be at least equivalent to existing pay-TV or free-to-air services. 

How Direct To Home (DTH) Works

Unlike earlier programming, the provider's broadcast is completely digital, which means it has much better picture and sound quality (see How Digital Television Works for details). Early satellite television was broadcast in C-band radio -- radio in the 3.7-gigahertz (GHz) to 6.4-GHz frequency range. Digital broadcast satellite transmits programming in the Ku frequency range (11.7 GHz to 14.5 GHz ).

The Components
There are five major components involved in a direct to home (DTH) or direct broadcasting (DBS) satellite system: the programming source, the broadcast center, the satellite, the satellite dish and the receiver.

• Programming sources are simply the channels that provide programming for broadcast. The provider doesn't create original programming itself; it pays other companies (HBO, for example, or ESPN) for the right to broadcast their content via satellite. In this way, the provider is kind of like a broker between you and the actual programming sources. (Cable TV companies work on the same principle.)
• The broadcast center is the central hub of the system. At the broadcast center, the TV provider receives signals from various programming sources and beams a broadcast signal to satellites in geosynchronous orbit.
• The satellites receive the signals from the broadcast station and rebroadcast them to Earth.
• The viewer's dish picks up the signal from the satellite (or multiple satellites in the same part of the sky) and passes it on to the receiver in the viewer's house.
• The receiver processes the signal and passes it on to a standard TV.

Satellite TV providers get programming from two major sources: national turnaround channels (such as HBO, ESPN and CNN) and various local channels (the ABC, CBS, Fox, NBC and PBS affiliates in a particular area). Most of the turnaround channels also provide programming for cable TV, and the local channels typically broadcast their programming over the airwaves.

Turnaround channels usually have a distribution center that beams their programming to a geosynchronous satellite. The broadcast center uses large satellite dishes to pick up these analog and digital signals from several sources.

Most local stations don't transmit their programming to satellites, so the provider has to get it another way. If the provider includes local programming in a particular area, it will have a small local facility consisting of a few racks of communications equipment. The equipment receives local signals directly from the broadcaster through fiber-optic cable or an antenna and then transmits them to the central broadcast center.

The broadcast center converts all of this programming into a high-quality, uncompressed digital stream. At this point, the stream contains a vast quantity of data -- about 270 megabits per second (Mbps) for each channel. In order to transmit the signal from there, the broadcast center has to compress it. Otherwise, it would be too big for the satellite to handle. In the next section, we'll find out how the signal is compressed.

Satellite signals have a pretty long path to follow before they appear on your TV screen in the form of your favorite TV show. Because satellite signals contain such high-quality digital data, it would be impossible to transmit them without compression. Compression simply means that unnecessary or repetitive information is removed from the signal before it is transmitted. The signal is reconstructed after transmission.

Standards of Compression
Satellite TV uses a special type of video file compression standardized by the Moving Picture Experts Group (MPEG). With MPEG compression, the provider is able to transmit significantly more channels. There are currently five of these MPEG standards, each serving a different purpose. DirecTV and DISH Network, the two major satellite TV providers in the United States, once used MPEG-2, which is still used to store movies on DVDs and for digital cable television (DTV). With MPEG-2, the TV provider can reduce the 270-Mbps stream to about 5 or 10 Mbps (depending on the type of programming).

Now, DirecTV and DISH Network use MPEG-4 compression. Because MPEG-4 was originally designed for streaming video in small-screen media like computers, it can encode more efficiently and provide a greater bandwidth than MPEG-2. MPEG-2 remains the official standard for digital TV compression, but it is better equipped to analyze static images, like those you see on a talk show or newscast, than moving, dynamic images. MPEG-4 can produce a better picture of dynamic images through use of spatial (space) and temporal (time) compression. This is why satellite TV using MPEG-4 compression provides high definition of quickly-moving objects that constantly change place and direction on the screen, like in a basketball game.

MPEG StandardsAll MPEG standards exist to promote system interoperability among your computer, television and handheld video and audio devices. They are:  MPEG-1: the original standard for encoding and decoding streaming video and audio files. MPEG-2: the standard for digital television, this compresses files for transmission of high-quality video. MPEG-4: the standard for compressing high-definition video into smaller-scale files that stream to computers, cell phones and PDAs (personal digital assistants). MPEG-21: also referred to as the Multimedia Framework. The standard that interprets what digital content to provide to which individual user so that media plays flawlessly under any language, machine or user conditions.

At the broadcast center, the high-quality digital stream of video goes through an MPEG encoder, which converts the programming to MPEG-4 video of the correct size and format for the satellite receiver in your house.

Encoding works in conjunction with compression to analyze each video frame and eliminate redundant or irrelevant data and extrapolate information from other frames. This process reduces the overall size of the file. Each frame can be encoded in one of three ways:

• As an intraframe, which contains the complete image data for that frame. This method provides the least compression.
• As a predicted frame, which contains just enough information to tell the satellite receiver how to display the frame based on the most recently displayed intraframe or predicted frame. A predicted frame contains only data that explains how the picture has changed from the previous frame.
• As a bidirectional frame, which displays information from the surrounding intraframe or predicted frames. Using data from the closest surrounding frames, the receiver interpolatesthe position and color of each pixel.

This process occasionally produces artifacts -- glitches in the video image. One artifact ismacroblocking, in which the fluid picture temporarily dissolves into blocks. Macroblocking is often mistakenly called pixilating, a technically incorrect term which has been accepted as slang for this annoying artifact. Graphic artists and video editors use "pixilating" more accurately to refer to the distortion of an image. There really are pixels on your TV screen, but they're too small for your human eye to perceive them individually -- they're tiny squares of video data that make up the image you see

The rate of compression depends on the nature of the programming. If the encoder is converting a newscast, it can use a lot more predicted frames because most of the scene stays the same from one frame to the next. In more fast-paced programming, things change very quickly from one frame to the next, so the encoder has to create more intraframes. As a result, a newscast generally compresses to a smaller size than something like a car race.

Encryption and Transmission 
After the video is compressed, the provider encrypts it to keep people from accessing it for free.Encryption scrambles the digital data in such a way that it can only be decrypted (converted back into usable data) if the receiver has the correct decryption algorithm and security keys.

Once the signal is compressed and encrypted, the broadcast center beams it directly to one of its satellites. The satellite picks up the signal with an onboard dish, amplifies the signal and uses another dish to beam the signal back to Earth, where viewers can pick it up.

When the signal reaches the viewer's house, it is captured by the satellite dish. A satellite dish is just a special kind of antenna designed to focus on a specific broadcast source. The standard dish consists of aparabolic (bowl-shaped) surface and a central feed horn. To transmit a signal, a controller sends it through the horn, and the dish focuses the signal into a relatively narrow beam.

The curved dish reflects energy from the feed horn, generating a narrow beam.

The dish on the receiving end can't transmit information; it can only receive it. The receiving dish works in the exact opposite way of the transmitter. When a beam hits the curved dish, the parabola shape reflects the radio signal inward onto a particular point, just like a concave mirror focuses light onto a particular point.

The curved dish focuses incoming radio waves onto the feed horn.

In this case, the point is the dish's feed horn, which passes the signal on to the receiving equipment. In an ideal setup, there aren't any major obstacles between the satellite and the dish, so the dish receives a clear signal.

In some systems, the dish needs to pick up signals from two or more satellites at the same time. The satellites may be close enough together that a regular dish with a single horn can pick up signals from both. This compromises quality somewhat, because the dish isn't aimed directly at one or more of the satellites. A new dish design uses two or more horns to pick up different satellite signals. As the beams from different satellites hit the curved dish, they reflect at different angles so that one beam hits one of the horns and another beam hits a different horn.

The central element in the feed horn is the low noise blockdown converter, or LNB. The LNB amplifies the radio signal bouncing off the dish and filters out the noise (radio signals not carrying programming). The LNB passes the amplified, filtered signal to the satellite receiver inside the viewer's house.

Satellite Receiver

Photo courtesy DirecTV

The end component in the entire satellite TV system is the receiver. The receiver has four essential jobs:

• It de-scrambles the encrypted signal. In order to unlock the signal, the receiver needs the proper decoder chip for that programming package. The provider can communicate with the chip, via the satellite signal, to make necessary adjustments to its decoding programs. The provider may occasionally send signals that disrupt illegal de-scramblers as an electronic counter measure (ECM) against illegal users.
• It takes the digital MPEG-2 or MPEG-4 signal and converts it into an analog format that a standard television can recognize. In the United States, receivers convert the digital signal to the analog National Television Systems Committee (NTSC) format. Some dish and receiver setups can also output anHDTV signal.
• It extracts the individual channels from the larger satellite signal. When you change the channel on the receiver, it sends just the signal for that channel to your TV. Since the receiver spits out only one channel at a time, you can't tape one program and watch another. You also can't watch two different programs on two TVs hooked up to the same receiver. In order to do these things, which are standard on conventional cable, you need to buy an additional receiver.
• It keeps track of pay-per-view programs and periodically phones a computer at the provider's headquarters to communicate billing information.

Receivers have a number of other features as well. They pick up a programming schedule signal from the provider and present this information in an onscreen programming guide. Many receivers have parental lock-out options, and some have built-in digital video recorders (DVRs), which let you pause live television or record it on a hard drive.

These receiver features are just added bonuses to the technology of satellite TV. With its movie-quality picture and sound, satellite TV is becoming a popular investment for consumers. Digital cable, which also has improved picture quality and extended channel selection, has proven to be the fiercest competitor to satellite providers. The TV war is raging strong between satellite and digital cable technologies as well as between the providers who offer these services. Once considered luxuries in most households, satellite and digital cable are becoming quite common as providers bundle TV with Internet and phone services to offer competitive deals and win over customers.

First Android OS Mobile-- G1 frm T-Mobile

Google Introduces an iPhone Rival Open to Whims

 Google and T-Mobile unveiled their answer to the iPhone on Tuesday, pulling the wraps off a slick mobile device that combines a touch screen and a keyboard and is aimed at putting the Internet in the pockets of millions of cellphone users.

Enlarge This Image

The T-Mobile G1 will cost $179, $20 less than the iPhone.

Related

Pogue: A First Look at Google’s New Phone

Times Topics: Google Inc.

Enlarge This Image

Jacob Silberberg/Reuters

The Google founders Larry Page, left, and Sergey Brin introduced the G1 on Tuesday in New York. The G1, Google’s smartphone joint venture with T-Mobile, will have an applications store.

The T-Mobile G1, which will be available in the United States on Oct. 22, is the first mobile phone to be powered by Google’s Android operating system. It represents a milestone in Google’s efforts to extend its dominance of the PC-based Internet to mobile phones and further loosen the control that wireless carriers have over what consumers can do with their phones.

Analysts said that the G1 did not represent the kind of revolutionary change in design and function that Appleintroduced last year with the iPhone. But the G1 is likely to further accelerate two trends that will have a lasting impact on the wireless industry: the growing use of the Internet on the go, and the ability of consumers to customize their phones with their favorite functions.

“I am not sure people are going to be lining up at stores for this device,” said Rajeev Chand, an analyst with Rutberg & Company. “The iPhone was a game changer from a consumer perspective. The Google phone may be more of game changer from an industry perspective.”

The G1, which is made by the Taiwanese electronics maker HTC, has a large color touch screen that slides out to expose a full keyboard. It also has a 3-megapixel camera, G.P.S. navigation, Wi-Fi access and an Internet browser. It will sell for $179, or $20 less than the iPhone, with a two-year voice and data plan.

“This is as good a computer as you had a few years ago,” said Google’s co-founder Larry Page, who along with co-founder Sergey Brin arrived on Rollerblades at the New York stage where Google and T-Mobile held a news conference to unveil the G1.

Although several applications, including Google’s search, maps, Gmail and YouTube, come installed on the phone, the G1 is also meant to encourage third-party developers to create programs to run on it. Like Apple, Google will include an applications store, called the Android Marketplace, where the owners of the G1 and future Android-powered phones will be able to download those programs.

Google said that developers would have virtually unfettered access to the marketplace, leaving it up to consumers — not Google or T-Mobile — to decide what they want to run on their phones.

While the G1 is expected to compete with high-end smartphones like the iPhone and the BlackBerry line of devices made by Research in Motion, Google’s aims are far different from those of its rivals.

Google makes the Android software available for free to carriers and handset makers who want to use it to power their own devices. Google hopes that many will choose to do so, populating the market with mobile phones that have easy access to Google’s services. Just as it does on the PC-based Internet, Google hopes to earn money from advertising.

“For Google, Android is a cash drain,” said James Faucette, an analyst with Pacific Crest Securities. “They are going to lose money on Android as an operating system. They hope to make it up from the services that they are delivering through their infrastructure and servers.”

While Google is betting on the success of Android, it also stands to benefit from the success of other smartphones, as their owners tend to surf and search the Internet much more actively than users of less advanced phones. Indeed, Google said earlier this year that its mobile service received a disproportionate amount of traffic from iPhone users.

“We want people out there to use the Internet on their phones a lot,” Mr. Brin said in an interview. “It actually doesn’t matter if it is Android, the iPhone or something else.”

T-Mobile, is counting on the G1 to increase its sale of data plans and said it believed the devices would appeal to consumers and business users.

“I think frankly this device will have mass appeal,” said Cole Brodman, chief technology and innovation officer of T-Mobile USA, a subsidiary of Deutsche Telekom.

Common Admission Test (CAT) Pattern

The Common Admission Test (CAT) is an all-India test conducted by the Indian Institutes of Management (IIMs) as an entrance exam for the management programmes of its seven business schools.

The test is multiple-choice based and traditionally comprises three sections that span the domains of arithmetical problem solving, geometry, statistics, data interpretation, logical reasoning, puzzles, and English language skills. It is held on the third Sunday of November each year. The test duration was two hours prior to year 2006, but since 2006, it has been extended to two and a half hours. The total number of questions has varied from 180 (prior to year 2000) to 150 (from 2001 to 2003) and has gradually decreased to 75 (in 2006 and 2007). This trend has seen the CAT evolve from a speed-based test to an exam that evaluates fundamental abilities of candidates in the aforementioned areas.

It is neither expected, nor possible, that all the questions be answered, so the CAT is also said to test the candidates' ability to prioritize under pressure.

The CAT is the first step for admission to the IIMs. After the test, by the second week of January next year, the IIMs declare exam scores and put up a list of candidates who are eligible for the next stage of a group discussion and an individual interview. The scores are relative and are calculated on a percentile basis for individual sections as well as for the total. Candidates invited for the next stage usually possess total scores that are in excess of 99 percentile and, more importantly, also possess balanced scores across all the individual sections.

More than 200,000 (230,000 in the year 2007) students compete for about 1500 seats in the IIMs.

CAT (as it is most commonly known across India) has evolved from a speed based simple test into a test which demands more proficiency in concepts and fundamentals.It is designed in such a way that it tests a candidate's analytical and logical abilities.

CAT Exam is Unpreditable because

1) No fixed Syllabus

2)No fixed Format

3) Negative Marking Impact 

Course Structure

1)Quants-------------(Arithmetic,Geometry,Algebra)

2)Data Interpretation (DI)

a) Data Interpretation: Interpreat the given data which is in the form of tables,charts,graphs (bar,pie)

b)Data Sufficiency: analyse the given data sufficient or not

c) Logical Ability: Connective logic, clocks,calendars,Blood relations,seating arrangement,logistics,networks

d)Logical Reasoning: analysis of argument

3)Verbal Ability:

a)Grammar

b)Vocabulary

c)Verbal Structures: para jumbles,para completion,summaries,facts,inferience,judgement,upstream/downstream

4)Reading Comprehension:

Some Modifications for CAT-2k9

1) 50% Marks in graduation

2)Duration changed from 120 min to 150 min

3) Number of multiple choices from 4 to 5

4)some rumours regarding CAT online tests from 2k9

Advantage if CAT becomes online

1) Flexibility: Examination centres open 24x7x365 

2)Validity extends from 1 year to 3 years

2) Any one can take test for every 3 months until he/she  gets good score

OMETS(other Management Entrance Tests)

1) XAT

2)SNAP

3)JMET(conducted by iit's and iisc)

4)IIFT

5)FMS

6)TISS

Evaluation Sheet (weightage):

CAT Score --30%

X standard --5%

XII standard--5%

Graduation--5%

work Exp----5%

Essay Writting-10%

GD-----------10%

PI------------20%

Quality of Academics--5%

Quality of Work Experience--5%