INTERNET

What is the INTERNET?

A   Introduction

      Areas to be covered:

    a)What are protocols?

     A standard set of regulations and requirements that allow two electronic items to connect to and exchange information with one another. Protocols regulate data transmission among devices as well as within a network of linked devices through both error control and specifying which data compression method to use. In particular, protocols decide: the method of error checking, how to compact data (if required), how the transmitting device signals that it has concluded sending data, and how the receiving device signals that it has completed receiving data.
    Protocols are simple rules created to standardize a particular network activity. They are  simply some scripts that make up rules to determine a specific standard that should be used worldwide by everyone for a specific purpoes such as file transmission, authentication, verification etc.
    Protocols typically do their tasks that is, they do what they are programmed for. They simply trigger when their functions is called such as transmission, validation, verification etc.
    It typically, runs the script it had been coded with and follows the standard rule specified in it.
    We get the necessary output of it after all which will be a standard and security protocol.

    Example of protocols are

       IP (Internet Protocol)
       IPSec (Internet Protocol Secured)
       IPv6 (Internet Protocol Version 6)
       HTTP (Hyper Text Transfer Protocol)
       MPLS (Multi Protocol Label Switched)
       SMTP (Simple Mail Transmission Protocol)
       POP (Post Office Protocol)
       DHCP (Dynamic Host Configuration Protocol)

    b)What is TCP/IP

      
TCP/IP (Transmission Control Protocol/Internet Protocol) is the basic communication language or protocol of the Internet. It can also be used as a communications protocol in a private network (either an intranet or anextranet). When you are set up with direct access to the Internet, your computer is provided with a copy of the TCP/IP program just as every other computer that you may send messages to or get information from also has a copy of TCP/IP.
TCP/IP is a two-layer program. The higher layer, Transmission Control Protocol, manages the assembling of a message or file into smaller packets that are transmitted over the Internet and received by a TCP layer that reassembles the packets into the original message. The lower layer, Internet Protocol, handles the address part of each packet so that it gets to the right destination. Each gateway computer on the network checks this address to see where to forward the message. Even though some packets from the same message are routed differently than others, they'll be reassembled at the destination.

TCP/IP uses the client/servermodel of communication in which a computer user (a client) requests and is provided a service (such as sending a Web page) by another computer (a server) in the network. TCP/IP communication is primarily point-to-point, meaning each communication is from one point (or host computer) in the network to another point or host computer. TCP/IP and the higher-level applications that use it are collectively said to be "stateless" because each client request is considered a new request unrelated to any previous one (unlike ordinary phone conversations that require a dedicated connection for the call duration). Being stateless frees network paths so that everyone can use them continuously. (Note that the TCP layer itself is not stateless as far as any one message is concerned. Its connection remains in place until all packets in a message have been received.)
Many Internet users are familiar with the even higher layer application protocols that use TCP/IP to get to the Internet. These include the World Wide Web's Hypertext Transfer Protocol (HTTP), the File Transfer Protocol (FTP), Telnet (Telnet) which lets you logon to remote computers, and the Simple Mail Transfer Protocol (SMTP). These and other protocols are often packaged together with TCP/IP as a "suite."
Personal computer users with an analog phone modem connection to the Internet usually get to the Internet through the Serial Line Internet Protocol (SLIP) or the Point-to-Point Protocol (PPP). These protocols encapsulate the IP packets so that they can be sent over the dial-up phone connection to an access provider's modem.
Protocols related to TCP/IP include the User Datagram Protocol (UDP), which is used instead of TCP for special purposes. Other protocols are used by network host computers for exchanging routerinformation. These include the Internet Control Message Protocol (ICMP), the Interior Gateway Protocol (IGP), the Exterior Gateway Protocol (EGP), and the Border Gateway Protocol (BGP).

    c)How does information travel through the Internet?

The Internet is based on packet-switched protocols. Information is carried in packets, which can be imagined as small parcels being passed from computer to computer. Large chunks of data are usually broken up into several smaller packets before being sent through the network. The delivery mechanism, or protocol, that is used to encode the packet ensures safe transit, and provides a way of reconstructing the data when it reaches its destination. The protocols used on the Internet are referred to as TCP/IP, standing for Transmission Control Protocol / Internet Protocol.
As a switched network, the physical connections between computers do not matter as far as Internet traffic is concerned — the protocols ensure that guaranteed information delivery is more important than speed or use of a particular route. This means that a sequence of packets might arrive out of order, with some travelling through the net by a faster, shorter route than others. TCP/IP provides the means for your software to piece together those packets into meaningful data. The ability to take different routes through the network is a fundamental part of the original design of TCP/IP, as it allows the Internet to route around damaged areas of the network.

    d)How does the connection work from home?

To connect from home you need several things. Apart from a computer (obviously!) you'll need a phone connection, a modem or ADSL router, and some Internet software. Things will be easier if you're using a relatively recent operation system, such as Windows Vista/XP or MacOSX, but it's possible to connect with older or more obscure systems.
With a modem and the appropriate software, you can dial up another modem connected to another computer, and establish a network connection with it. Usually, this computer is linked into the Internet, and so you're online.
With an ADSL modem or router, a similar procedure happens, but a filter splits the telephone line into voice and data (low and high frequencies) and your router negotiates a connection with the ADSL equipment in the telephone exchange.

Figure 1.2. ADSL Frequency Spectrum

 B   ISP (Internet Service Provider )

      Areas to be covered :

    a) What is ISP?

    An Internet Service Provider (also known as an ISP or even as an IAP, internet access provider) is a firm that offers subscribers access to the internet. This internet service provider maintains large runs of cabling and maintains network services in order to transfer and deliver web content to those paying the subscription fee. Typically, these internet service providers focus on DSL, Cable modem, wireless, and more recently, dedicated high-speed interconnects such as T1 or fiber optic service (typically abbreviated Fios). While far less common, ISPs still offer dial up internet service, which is gradually become a phased out. All in all, there are many different types of Internet Service Providers, and within each and every internet service provider there are often varying levels of service, coverage, as well as personal customer service that comes attached with it. An Internet Service Provider is a complete package of services, which should be researched and considered before an Internet Service Provider is selected.

For most users, the most important qualification (beyond the ever present price point) is the speed of the connection. Depending on the intended use, there are a myriad of different internet services, and even varying levels of coverage within each and every service. The slowest of these is dial-up internet service. Modern dial-up transfers web content at a maximum rate of 56.6 kilobits per second. In the early days of internet service, this was typically sufficient, as websites were designed with a lean mentality, with very little imagery and a heavy emphasis on text, and text based linking. As time has progressed however, most websites assume that the user is on a high speed connection, and have therefore loaded their website with visual flair and high file size images. What was once acceptable no longer is for most web users, who opt to selecting a faster service.

Mid-Range services available for home include Cable Internet or Digital Subscriber Line (DSL) service. While DSL is available as slow as 128 Kilobits per second (just slightly more than twice the speed of dial-up service) most of these providers have since upgraded their capacity and provide service as fast as 3000 Kilobits per second. For most people, this is sufficient however there are currently faster services available to those who either desire them, or require them to operate their business.

For those simply not interested in paying for internet access, there are a very small number of Free ISPs available. These providers provide internet service free of charge, typically funded through advertising revenue (much like television broadcasts on most stations). Unfortunately, this variety of ISP is gradually falling by the wayside. Netzero, one the earliest example of this service no longer provides an ad supported internet service, and instead focuses on low priced services such as dial up.

All in all, an Internet Service Provider has the very complicated job of setting up and maintaining a network to connect its users to the internet. The inner workings of an ISP vary significantly from company to company, and much of their inner workings are company secret. It's difficult to understand just how internet service providers operate, however from the buyer's perspective the process of using an ISP are incredibly simple. Once a level of connectivity is decided upon, it's simply up to the buyer to research their alternatives, and determine the best solution for their budget and needs.

b)Connecting using ISP and how to choose an ISP: Dialup , broadband or mobile ?

Internet Service Providers (ISPs) are companies that connect you to the internet. There are various types of ISPs. In order to select the best ISP, you need to know what technology is available, which technology is right for you, how much speed you need, and what the service will cost.

Most ISPs use either an existing phone line (for dial-up or DSL), a cable television line, or a satellite connection to connect you to the internet. Depending on your area, some connections may not be available.

 Most ISPs use either an existing phone line (for dial-up or DSL), a cable television line, or a satellite connection to connect you to the internet. Depending on your area, some connections may not be available.

c)Choosing a broadband provider .

There are a lot of factors to consider when comparing broadband packages, but perhaps the most important are speed, cost and contract length. With so many providers, contracts, offers and packages to choose from, the first step is to know exactly what you need.

What kind of broadband package do I want ?

• Beginner's broadband. If you are just starting out, it's likely that you're looking for a package that's easy to set up, not too expensive and offers good customer support.
• Heavy-Use broadband. You know if you are a heavy-user if you enjoy downloading oodles of songs and movies using peer-to-peer software, or you're a big fan of online gaming. Either way, our heavy-use packages are the ones to look out for.
• Business broadband. These packages differ from consumer deals as they offer extras like static/fixed-IPs, webspace and email addresses as well as routers and secuity suites.
• Mobile broadband. If you access the Internet primarily from your laptop, then mobile broadband is an option worth considering - whether to be used at home or on the go. Mobile broadband providers will send you a 'dongle' (modem) that you plug into the USB slot on your laptop to access the Internet, at broadband speeds, wherever there's mobile phone coverage.

More recently MiFi dongles have arrived too, which allow you to share a single mobile broadband connection between multiple web enabled devices simultaneously.

• Family broadband. With more and more devices like laptops, tablets, TVs, set-top boxes and gaming consoles connecting to the Internet, families have specific needs that are best catered for by certain providers.

d)Measuring Bandwidth

   What is bandwidth? There are two definitions, both of which are important to Screencast.com account owners.

1. Bandwidth is a measure of the amount of data that can be transmitted through a connection over a given amount of time.
2. Bandwidth, also called data transfer rate, is usually expressed in bits per second (bps).

The Amount of Data Transferred Through a Connection Over Time

Bandwidth is simply a measure of the amount of data that can be transmitted through a connection over a given amount of time. Bandwidth, also called data transfer rate, is usually expressed in bits per second (bps).

When a Screencast.com account owner shares content and that content is viewed, they are billed for the bandwidth required to transfer the content throughout  a particular billing cycle. Overall, this can be thought of as the cost of sharing content. At the beginning of a billing cycle, the total bandwidth amount starts over.
For a rough calculation of how much bandwidth you might use, assume you have a 10 MB file and it is downloaded once, 10 MB of bandwidth is used. If that same 10 MB file is downloaded seven times, 70 MB of bandwidth is used. Partial downloads only use bandwidth for the part of the file downloaded, so a file’s views multiplied by its size rarely equals its bandwidth consumed.
While it may be difficult to figure out exactly how much bandwidth you will need since you may not know how many people will view your content or how much content you will make available for viewing, Screencast.com makes it easy  for you  to purchase extra blocks of rollover bandwidth. If all of the extra bandwidth is not consumed in one billing cycle, it will roll over to the next one until it is all used up.
For more information on this subject, watch this helpful  video.

Bandwidth or File Transfer Rate

Bandwidth is synonymous with capacity. Every machine on the Internet is connected by a cable or another type of connection. This cable has a capacity; it can carry a certain amount of information through it, similar to a hose. This cable may have a high or low capacity. If you compare a garden hose to a fire hose, more water can pass through the fire hose in a minute than a garden hose.

The slowest of these capacities is the bandwidth of the line; it’s the fastest you can communicate between the ends. Think of the cable as a long tube with someone pouring water into it on one end, and someone draining it out the other. You cannot take out more than was put in, and if you pour it in too fast the water will spill (losing data).

For example, a 28.8 kbps dialup modem connection is much slower than a cable modem connection. The cable modem connection can download more data than the 28.8 kbps dialup modem connection can over the same period of time. The cable modem has a higher bandwidth connection than the 28.8 kbps dialup connection does. High bandwidth allows fast transmission of data or high volume transmission just like the fire hose.

File Size, Bit Rate, Bandwidth and Data Transmission

File size is measured in bytes. One kilobyte (K or KB) equals about 1,024 bytes. For example, a small image file might be 20K or about 20,000 bytes in size.

Measurements and Conversions

 

Data Transmission

Data transmission measured in bits per second (bps) is called the baud rate or bit rate - it is the measure of bandwidth. It is commonly measured in thousands of bits per second or kilobits per second. The abbreviation for kilobits per second is kbps or simply k. One kilobit equals about 1,000 bits.If a computer can receive 5KB in a second, it would take 4 seconds for it to receive a file 20K in length.

But bandwidth is not measured in bytes—it is measured in bits. 1 byte contains 8 bits. So, if a computer can receive 5KB (5,000 bytes) in one second, it can receive 40,000 bits per second. 5,000 bytes x 8 bits = 40,000 bits per second or 40 kbps.

If a computer connects to the Internet using a 56 kbps dialup modem, in theory, it means that the computer could receive 56,000 bits per second (56 kbps). That would mean that the computer could receive about 7,000 bytes per second. Remember that a byte equals 8 bits, so 56,000 bps/ 8 bits = 7,000 bytes.

So, to receive the 20K image file, the 56 kbps dialup connection would require slightly less than 3 seconds to receive the file (20K/7,000 bytes=2.85 seconds).

Note: A 56 kbps modem cannot actually communicate at 56 kbps. In reality it’s more like 35-45 kbps. A 56 kbps modem connection generally only provides 35-45 kbps of bandwidth.

Bandwidth and Streaming Media File Transmission

Computer video files are basically a number of still images called frames combined sequentially into one file. When the file is played on a player such as Windows Media Player, it goes through the video file and displays each frame sequentially in quick succession to create the illusion of motion similar to a video film rolling through a movie projector.

When a file is transferred, frames are continuously delivered from the computer transferring the video to the computer playing it. Each frame is displayed as it is received.

For example, consider a computer connected to the Internet using a dialup modem. If the modem is connected at 40 kbps, it could receive 5,000 bytes (5 KB) of data per second. If each frame of the video was only 5K then the modem could only receive 1 frame per second.

Commercial motion pictures are 24 fps (frames per second), television is 30 frames per second. The more frames per second (fps), the smother the video playback appears to the viewer. So, a 1 fps video is a very slow and choppy video. The number of frames per second (fps) is also called the frame rate.

With a higher bandwidth connection, more frames per second could be received. With a 128 kbps ISDN connection for example, 32 5K frames could be delivered per second.

But, a 5K image or frame is not very big. A small 320x200, 16 bit JPEG file can easily be 20K in size. So, for the modem connected with only 40 kbps of bandwidth, it would take 4 seconds to receive only one frame of the video! At that rate, the video would degrade into a slide show, and not be a video at all.

This is the reason why many videos that you see online or on news sites are very small, and why a dialup Internet connection just does not have enough bandwidth to enjoy a very rich multimedia experience.

C  Who governs/regulates/controls the Internet?

Who controls the Internet? This is a question that has reemerged in recent weeks as the crisis in the Middle East and North Africa has unfolded. Reports of Egypt's shutdown of network operators left many asking whether other nations, including the U.S., could flip a "kill switch" and bring down the Internet in their respective nations. (For the record, the U.S. government could not easily do so.) Egypt is not the first country to deny service to the Internet for its citizens -- Iran and China, for example, both have blocked traffic, content, and services. Indeed, North Korea has blocked all Internet access to its citizens.

Underpinning the question of control is a belief by many that the Internet is a global commons analogous to land, sea, air, and space -- those resources for which the international community has, out of necessity, established norms and institutions to allow for (generally) peaceful coexistence. The analogy, however, is not perfect. The Internet doesn't resemble the four commons much at all.

On one level, one can argue that the Internet is a telecommunications network of telecommunications networks, and, with few exceptions, each network is physically located within or among state boundaries and explicitly owned by someone -- not typically a government. At a fundamental level, the Internet is just an agreement between networks to exchange data in a certain standardized way, and each of the networks and the computers they interconnect is subject to some legal authority based on location or ownership.

A nation can close land borders, block seaports, and restrict air space (to a certain degree), but it cannot, short of shutting down almost all of its Internet communications networks or providing strict monitoring and filtering (a la China), "take down" the Internet. By their nature, networks do not end at borders and the underlying content and communications cross nations and regions, providing a new fifth global common.

We are seeing this fight over the fifth global common extending beyond nations' internal network into a debate over who controls the complex interconnected network of unique identifiers that allow computers on the Internet to find each other.

The Washington Post reported this week that the Obama Administration has raised concerns that the Internet Corporation for Assigned Names and Numbers' (ICANN) is not giving more nations authority to voice objections to web addresses that make up the addressing system for the Internet. ICANN, under a contract from the U.S. government, runs global domain name system operations and is authorized to enter into contracts with registries and registrars for the distribution of addresses, manage IP address space assignments, and govern top-level domain names. The U.S., through the Commerce Department, pushed for ICANN to allow nations to veto domain names that they found offensive; ICANN's board responded by deciding that it would only consider such objections as non-binding advice.

While it may seem odd for the U.S. to be asking for other nations to have more authority, its request is one to preempt a push by nations such as China and Russia to move authority over domain name server operations from the ICANN-U.S. government regime to the United Nations. Other nations fear that the U.S. might, if it chose to discontinue its contract with ICANN, seek to run the operations itself, thereby potentially controlling a key part of the Internet's operations and dictating this fifth common beyond its border. Such a possibility is unlikely, especially as there are safeguards and steps in place to protect against undue influence.

Those concerns demonstrate the tension for this potential global common. The struggle to tackle the rules of the road on this common will only become harder as technology advances, telephone and Web services continue to converge, and cloud computing and social networking become more common. Unfortunately, even if a solution does arise, it must be a malleable one, as the Internet by its very nature (and unlike land, sea, air, and space) is constantly evolving.

D   Who owns the Internet?

Who Owns the Internet?Control over the Net is in the hands of a few big companies. Is this a job for Judge Green? Nancy Weil, IDG News Service

No one owns the Internet. This is a truism we can all stand behind.

But the infrastructure on which the global network runs is owned by a handful of powerful corporations that can, and often do, use control over the Internet backbone as a tool in business negotiations. Some fear their influence is strangling smaller companies and reducing customer choice.

"I can give you an example that shows that the Internet is owned by someone," says Jilani Zeribi, a senior analyst at market researcher Current Analysis. "Look at old peering arrangements, which were basically, 'I'll connect to your network, you carry my data and I'll carry yours.'"

"The carriers started to realize that smaller ISPs [Internet service providers] were free-riding on their network, so they started charging for peering arrangements," Zeribi says.

In the Hands of Few

A relatively small number of companies own and operate the fiber and the cables of the Internet infrastructure. They include AT&T, UUNet (a division of MCI WorldCom), GTE's Internetworking, Global Crossing, Qwest Communications International, and PSINet.

It's nearly impossible to measure exactly who owns how much. It's generally accepted that UUNet owns 30 percent of the backbone, and AT&T claims the number-two spot.

Perhaps more important than ownership percentages are questions about what an ownership stake means. These companies have invested millions in building and maintaining the infrastructure. What kind of power do the Net owners claim, and how might they wield that power--either for good or for nefarious ends?

Another sticky issue relates to co-location, the place where a cluster of ISPs keeps their servers and other hardware. This is typically owned by a major vendor like UUNet. Other concerns relate to network access points, which is where ISPs trade packets with other ISPs.

NAPs are supposed to be neutral territory, not subject to squabbles like those over peering arrangements. But they aren't always. "Getting in and out of the NAPs is tricky," says Vince DiBiase, senior vice president and chief sales officer for ICG Communications, a communications service provider.

Open for Competition?

Some say the Internet business is so competitive that the threat of newcomers can always keep big players from wielding power unfairly. But DiBiase and others suggest large infrastructure players and large service providers bolster each other's position.

Again, he points to UUNet (whose parent company, MCI WorldCom, would not respond to inquiries for this report). UUNet provides Internet backbone for America Online. Given its millions of global Internet subscribers and its corporate growth, UUNet won't approach its AOL deal the same way as it does involving agreements with smaller ISPs.

Instead, AOL gets a much better pricing deal because of the huge volume of traffic it brings to the UUNet backbone. "That's a cost advantage that a smaller ISP doesn't get," DiBiase says.

Will History Repeat Online?

Examples of power-wielding by the Internet infrastructure heavyweights reflect the influence of the phone companies, who were quick to jump into the business. After all, the telephone infrastructure was already in place, and dial-up was the first means of Internet access. Some are troubled by the extension of phone company power into the Internet.

"You have the entire history of the big phone companies trying to avoid orders by regulatory commissions to open their networks to competition," says James Love, director of the Consumer Project on Technology, a Washington, D.C. organization started in 1995 by consumer advocate Ralph Nader.

The effect, in Love's view, is "less competition in the ISP market, high barriers to entry, more consolidations and mergers, and eventually much more monopolistic control over the Internet." In other words, less choice for the consumer.

"There are clear dominant players in the Internet, and clear issues when one player comes to dominate too much," Zeribi says. He cites UUNet, adding, "If they raise their prices on peering, for example, that will have immediate and direct consequences on other companies."

Competition Keeps 'em Honest

There is disagreement about how far those consequences might extend.

Some industry observers contend the market is so highly competitive as to be, in effect, self-correcting. If one company started throwing around its weight to the detriment of others, market forces would take over.

"There's a minor concern by a lot of people who don't understand the market power of the Internet, and that includes the U.S. Justice Department and the European Union," says David Kunkel, vice chairman and executive vice president of PSINet. He is skeptical that even the biggest companies could rule the Net.

Leonard Kleinrock, who played a central role in establishing data networking technology with early academic papers he wrote, agrees. He writes, "The network is so flexible, and it's such an open network in terms of competition and architecture that if anyone began to flex some power, someone else would step in to compete with them."

Kleinrock is a professor of computer science at the University of California at Los Angeles, and is also chairman and founder of Normadix, a network startup. Kleinrock was a key figure in the development of the Advanced Research Projects Agency network, better known as the ARPANET, the precursor to the Internet.

He doesn't doubt that large Internet infrastructure owners can and have taken advantage of their size in business negotiations. But Kleinrock and many who deal with the Internet on a day-to-day basis agree that no coterie of big players has dominant power.

For Kleinrock, the issue of wielding power over the Internet infrastructure and exerting undue pressures boils down to one thing: "I think the bottom line is that no one is in a position to close down the Internet."