Interesting Facts about India

GenxTechno Tags: my india, facts about india, about india, india, indian history, my pride, great india

• India never invaded any country in her last 100000 years of history.
• When many cultures were only nomadic forest dwellers over 5000 years ago, Indians established Harappan culture in Sindhu Valley (Indus Valley Civilization)
• The name 'India' is derived from the River Indus, the valleys around which were the home of the early settlers. The Aryan worshippers referred to the river Indus as the Sindhu.
• The Persian invaders converted it into Hindu. The name 'Hindustan' combines Sindhu and Hindu and thus refers to the land of the Hindus.
• Chess was invented in India.
• Algebra, Trigonometry and Calculus are studies, which originated in India.
• The 'Place Value System' and the 'Decimal System' were developed in India in 100 B.C.
• The World's First Granite Temple is the Brihadeswara Temple at Tanjavur, Tamil Nadu. The shikhara of the temple is made from a single 80-tonne piece of granite. This magnificent temple was built in just five years, (between 1004 AD and 1009 AD) during the reign of Rajaraja Chola.
• India is the largest democracy in the world, the 6th largest Country in the world, and one of the most ancient civilizations.
• The game of Snakes & Ladders was created by the 13th century poet saint Gyandev. It was originally called 'Mokshapat'. The ladders in the game represented virtues and the snakes indicated vices. The game was played with cowrie shells and dices. In time, the game underwent several modifications, but its meaning remained the same, i.e. good deeds take people to heaven and evil to a cycle of re-births.
• The world's highest cricket ground is in Chail, Himachal Pradesh. Built in 1893 after leveling a hilltop, this cricket pitch is 2444 meters above sea level.
• India has the largest number of Post Offices in the world.
• The largest employer in the world is the Indian Railways, employing over a million people.
• The world's first university was established in Takshila in 700 BC. More than 10,500 students from all over the world studied more than 60 subjects. The University of Nalanda built in the 4th century was one of the greatest achievements of ancient India in the field of education.
• Ayurveda is the earliest school of medicine known to mankind. The Father of Medicine, Charaka, consolidated Ayurveda 2500 years ago.
• India was one of the richest countries till the time of British rule in the early 17th Century. Christopher Columbus, attracted by India's wealth, had come looking for a sea route to India when he discovered America by mistake.
• The Art of Navigation & Navigating was born in the river Sindh over 6000 years ago. The very word Navigation is derived from the Sanskrit word 'NAVGATIH'. The word navy is also derived from the Sanskrit word 'Nou'.
• Bhaskaracharya rightly calculated the time taken by the earth to orbit the Sun hundreds of years before the astronomer Smart. According to his calculation, the time taken by the Earth to orbit the Sun was 365.258756484 days.
• The value of "pi" was first calculated by the Indian Mathematician Budhayana, and he explained the concept of what is known as the Pythagorean Theorem. He discovered this in the 6th century, long before the European mathematicians.
• Algebra, Trigonometry and Calculus also originated in India.Quadratic Equations were used by Sridharacharya in the 11th century. The largest numbers the Greeks and the Romans used were 106 whereas Hindus used numbers as big as 10*53 (i.e. 10 to the power of 53) with specific names as early as 5000 B.C.during the Vedic period.Even today, the largest used number is Terra: 10*12(10 to the power of 12).
• Until 1896, India was the only source of diamonds in the world
  (Source: Gemological Institute of America).
• The Baily Bridge is the highest bridge in the world. It is located in the Ladakh valley between the Dras and Suru rivers in the Himalayan mountains. It was built by the Indian Army in August 1982.
• Sushruta is regarded as the Father of Surgery. Over2600 years ago Sushrata & his team conducted complicated surgeries like cataract, artificial limbs, cesareans, fractures, urinary stones, plastic surgery and brain surgeries.
• Usage of anaesthesia was well known in ancient Indian medicine. Detailed knowledge of anatomy, embryology, digestion, metabolism,physiology, etiology, genetics and immunity is also found in many ancient Indian texts.
• India exports software to 90 countries.
• The four religions born in India - Hinduism, Buddhism, Jainism, and Sikhism, are followed by 25% of the world's population.
• Jainism and Buddhism were founded in India in 600 B.C. and 500 B.C. respectively.
• Islam is India's and the world's second largest religion.
• There are 300,000 active mosques in India, more than in any other country, including the Muslim world.
• The oldest European church and synagogue in India are in the city of Cochin. They were built in 1503 and 1568 respectively.
• Jews and Christians have lived continuously in India since 200 B.C. and 52 A.D. respectively
• The largest religious building in the world is Angkor Wat, a Hindu Temple in Cambodia built at the end of the 11th century.
• The Vishnu Temple in the city of Tirupathi built in the 10th century, is the world's largest religious pilgrimage destination. Larger than either Rome or Mecca, an average of 30,000 visitors donate $6 million (US) to the temple everyday.
• Sikhism originated in the Holy city of Amritsar in Punjab. Famous for housing the Golden Temple, the city was founded in 1577.
• Varanasi, also known as Benaras, was called "the Ancient City" when Lord Buddha visited it in 500 B.C., and is the oldest, continuously inhabited city in the world today.
• India provides safety for more than 300,000 refugees originally from Sri Lanka, Tibet, Bhutan, Afghanistan and Bangladesh, who escaped to flee religious and political persecution.
• His Holiness, the Dalai Lama, the exiled spiritual leader of Tibetan Buddhists, runs his government in exile from Dharmashala in northern India.
• Martial Arts were first created in India, and later spread to Asia by Buddhist missionaries.
• Yoga has its origins in India and has existed for over 5,000 years.

Collaborative Computing & The Internet

GxTechno Tags: collaboration, collaborative, computing, collaborative comupting, internet

“What is “collaborative computing?” It is the term that, we believe, will replace the traditional notion of “groupware.” Groupware as we know it today focuses on the asynchronous aspect of human collaboration. E-mail, discussion lists, list servers, and similar software products help people to electronically exchange information. In other words, these products electronically extend a letter, a fax, and a filing cabinet.

Definition: Collaborative computing is a fertile mélange of technologies and techniques which facilitate people working together via computer-assisted means.

To communicate over a distance in real time, we invented the phone system. A phone conversation is an example of synchronous communication. The phone system serves us wonderfully. Is it the telephone the best possible real-time communication medium, though? It depends. Phones are ideal for person-to-person conversation, but when it comes to exchanging technical information, phones have information transfer limitations. Technical support over a telephone is imprecise and often difficult. It is much easier to share technical information in a shared web browser than try to describe the same content in a telephone conversation.

In general, communication with strong visual component, with content ranging from technical to marketing, is ill suited for telephone communication.

Collaborative computing is a term describing a variety of activities where people interact with one another using desktops, laptops, palmtops, and sophisticated digital cellular phones. As computers are best at handling data and representing information, person-to-person communication is enriched by an ability to share, modify, or collaboratively create data and information.

We believe collaborative computing is the future of the Internet. The Internet will evolve from its current role as a channel for information dissemination to a person-to-person communication medium. This is precisely where CollabWorx sees its role: we build, deploy, and support tools for personal interaction over the Internet.”

Traditional Collaboration – Groupware & Computer-Supported Cooperative Work

The long-standing history of office automation has lead to the classification of collaborative computing into two broad categories: (1) groupware ; and (2) computer-supported collaborative work (CSCW) . Defined as “computer-based systems that support groups of people engaged in a common task (or goal) and that provide an interface to a shared environment” , the primary focus of groupware is to provide a group interface for a shared task. In a similar vein, computer-supported cooperative work systems deal with how technology (specifically computer systems) can assist in the work process. These two areas are often combined into a single focus which addresses how groups of people can work together in a (logically) shared environment with the assistance of computer support.

Groupware systems span a spectrum of usage patterns and the illustrated time/place matrix is a well-known taxonomy. Systems which support synchronous activity are known as real-time groupware while those that support asynchronous activity (such as electronic mail) are non-real-time. Synchronous systems therefore offer a concurrent shared environment in which multiple users can interact simultaneously while asynchronous systems provide for serial non-shared interaction. As a rule, most groupware systems primarily support interaction along only one such dimension.

Groupware systems have also been classified based on application functionality, including the categories of message systems, multi-user editors, computer conferencing, intelligent agents, (group) decision support and coordination systems. An overview and discussion can be found in . Systems often span multiple categories in this taxonomy and can be used in an overlapping manner by a group to accomplish its goal. Consequently, collaboration can be seen as a blend of activities used in varying ways across multiple participants. Therefore, the utility of a collaborative environment is directly influenced by its openness and flexibility such that it can support the integration of different technologies to support various collaborative tasks.

To support this diversity within collaboration, several different perspectives exist in the application of groupware technologies; these include: distributed systems, communications, human-computer interaction, artificial intelligence and social theory. For practical purposes, many systems (with some exceptions, such as ) support group work according to a particular approach and with their own unique focus. Such an example would be workflow management systems ( WfMS ), which generally aim at assisting business or government groups in communicating, coordinating and collaborating with a special emphasis on the facilitation (i.e., automation and/or augmentation) of business processes. To do so, WfMS deal with temporal aspects such as activity sequencing, deadlines, routing conditions and schedules. They are typically “organizationally aware,” containing an explicit representation of organizational processes and often provide a rigid work environment consisting of roles, associated activities and applications. Such systems are usually highly valuable in their organizational context but are either built-for-purpose or require significant customization to meet the needs of a particular group.

Internet Culture

GxTechno Tags: internet, culture, internet culture, social impact

This study examines online culture by constructing an affective portrait of Internet users. Respondents were recruited through a highly visible advertisement on the Yahoo! search engine, and their sentiments were collected with a Web-based survey instrument using Osgood’s semantic-differential technique. The study had three particularly engaging findings: First, Internet users hold extremely intense and nuanced affective sentiments toward the components of their online world. Second, these sentiments vary with the amount of time Internet users spend online as well as their cumulative years of Internet experience. Third, men and women have slightly different affective responses toward many components of online culture, suggesting that despite the supposedly gender-free nature of the Internet, men and women experience somewhat different online social worlds.

Social Impact

The Internet has made possible entirely new forms of social interaction, activities and organizing, thanks to its basic features such as widespread usability and access. Social networking websites such as Facebook and MySpace have created a new form of socialization and interaction. Users of these sites are able to add a wide variety of items to their personal pages, to indicate common interests, and to connect with others. It is also possible to find a large circle of existing acquaintances, especially if a site allows users to utilize their real names, and to allow communication among large existing groups of people. Sites like meetup.com exist to allow wider announcement of groups which may exist mainly for face-to-face meetings, but which may have a variety of minor interactions over their group's site at meetup.org, or other similar sites.

The first generation is now being raised with widespread availability of Internet connectivity, with consequences for privacy, identity, and copyright concerns. These "Digital natives" face a variety of concerns that were not present for prior generations.

In democratic societies, the Internet has achieved new relevance as a political tool, leading to Internet censorship by some states. The presidential campaign of Howard Dean in 2004 in the United States became famous for its ability to generate donations via the Internet. Many political groups use the Internet to achieve a whole new method of organizing, in order to carry out Internet activism. Some governments, such as those of Iran, North Korea, Myanmar, the People's Republic of China, and Saudi Arabia, restrict what people in their countries can access on the Internet, especially political and religious content. This is accomplished through software that filters domains and content so that they may not be easily accessed or obtained without elaborate circumvention.

In Norway, Denmark, Finland and Sweden, major Internet service providers have voluntarily (possibly to avoid such an arrangement being turned into law) agreed to restrict access to sites listed by police. While this list of forbidden URLs is only supposed to contain addresses of known child pornography sites, the content of the list is secret. Many countries, including the United States, have enacted laws making the possession or distribution of certain material, such as child pornography, illegal, but do not use filtering software. There are many free and commercially available software programs, called content-control software, with which a user can choose to block offensive websites on individual computers or networks, such as to limit a child's access to pornography or violence.

The Internet has been a major source of leisure since before the World Wide Web, with entertaining social experiments such as MUDs and MOOs being conducted on university servers, and humor-related Usenet groups receiving much of the main traffic. Today, many Internet forums have sections devoted to games and funny videos; short cartoons in the form of Flash movies are also popular. Over 6 million people use blogs or message boards as a means of communication and for the sharing of ideas. The pornography and gambling industries have both taken full advantage of the World Wide Web, and often provide a significant source of advertising revenue for other websites. Although many governments have attempted to put restrictions on both industries' use of the Internet, this has generally failed to stop their widespread popularity.

One main area of leisure on the Internet is multiplayer gaming. This form of leisure creates communities, bringing people of all ages and origins to enjoy the fast-paced world of multiplayer games. These range from MMORPG to first-person shooters, from role-playing games to online gambling. This has revolutionized the way many people interact and spend their free time on the Internet. While online gaming has been around since the 1970s, modern modes of online gaming began with services such as GameSpy and MPlayer, to which players of games would typically subscribe. Non-subscribers were limited to certain types of game play or certain games. Many use the Internet to access and download music, movies and other works for their enjoyment and relaxation. As discussed above, there are paid and unpaid sources for all of these, using centralized servers and distributed peer-to-peer technologies. Some of these sources take more care over the original artists' rights and over copyright laws than others.

Many use the World Wide Web to access news, weather and sports reports, to plan and book holidays and to find out more about their random ideas and casual interests. People use chat, messaging and e-mail to make and stay in touch with friends worldwide, sometimes in the same way as some previously had pen pals. Social networking websites like MySpace, Facebook and many others like them also put and keep people in contact for their enjoyment. The Internet has seen a growing number of Web desktops, where users can access their files, folders, and settings via the Internet. Cyberslacking can become a serious drain on corporate resources; the average UK employee spent 57 minutes a day surfing the Web while at work, according to a 2003 study by Peninsula Business Services

Internet Congestion Control

GxTechno Tags: internet, congestion, internet congestion, tcp control, traffic control

The area of Internet congestion control was formed in 1986-1987 when the then ARPANET suffered ‘congestion collapse’. Congestion collapse had been predicted by Nagel in 1984. Congestion collapse occurs when mounting levels of traffic result in high packet loss inside the network, such that few or no packets are actually delivered to their destination, yet each link is highly loaded.

The initial response to ARPANET’s congestion collapse problem was to increase the capacity of the network. This helped temporarily, but the ARAPNET continued to suffer congestion collapses until a strategy to control the load of packets entering the network was developed. In 1988 Van Jackson enhanced the famous Transport control protocol (TCP) so that the transmission rate was responsive to the level of network congestion. TCP was made to reduce the rate of transmission of hosts when it sensed the network load was nearing congestion collapse. Since the introduction of this enhanced TCP, congestion collapse did not reoccur.

This history of the Internet reflects the two fundamental approaches to the problem of controlling congestion in networks 1) Capacity Provisioning and 2) Load control. Since Congestion collapse occurs when the load of packets placed onto the network exceeds the network’s capacity to carry the packets, the capacity provisioning approach is to ensure that there is enough capacity to meet the load. The load control approach is to ensure that the load of packets placed onto the network is within the capacity of the network. Capacity provisioning is achieved either by accurate performance analysis and traffic modeling, or the brute force approach of over provisioning. There is a range of load control strategies for networks, from connection admission control schemes through to best-effort flow control as on the Internet.

1. Congestion control principles.

1.1 What is congestion?
1.2 Congestion collapse.
1.3 Controlling congestion: design considerations.
1.4 Implicit feedback.
1.5 Source behaviour with binary feedback.
1.6 Stability.
1.7 Rate-based versus window-based control.
1.8 RTT estimation.
1.9 Traffic phase effects.
1.10 Queue management.
1.11 Scalability.
1.12 Explicit feedback.
1.13 Special environments.
1.14 Congestion control and OSI layers.
1.15 Multicast congestion control.
1.16 Incentive issues.
1.17 Fairness.
1.18 Conclusion.

2. Present technology.

2.1 Introducing TCP.
2.2 TCP window management.
2.3 TCP RTO calculation.
2.4 TCP congestion control and reliability.
2.5 Concluding remarks about TCP.
2.6 The Stream Control Transmission Protocol (SCTP).
2.7 Random Early Detection (RED).
2.8 The ATM‘Available Bit Rate’ service.

Internet Congestion

Internet refers to network of networks, so the network congestion is the situation in which an increase in data transmission than the network devices (routers and switches) can accommodate. This results in a proportionately reductions, in throughput.

Throughput is the amount of data that passes through the network per unit of time, such as the number of packets per second.

Packets are the fundamental unit of data transmission on the internet and all other TCP/IP networks, including most LANs.

For this we need buffer, buffer is a portion of a device’s memory that is set aside as a temporary holding place for data that is being sent to or received from another device. This ca result in delayed of lost packets, thus causing applications to retransmit the data, thereby adding more traffic and further increasing the congestion.

Congestion Collapse is the situation in which the congestion becomes so great that throughput drops to a low level and thus little useful communication occurs. It can be stable state with the same intrinsic load level that would by itself not produce congestion. This is because it is caused by the aggressive retransmission used by carious network protocols to compensate for the packet loss that occurs as a result of congestion, a retransmission that continues even after the load is reduced to a level that would not have induced congestion by itself.

Congestion Control

It is the process that is used to reduce congestion in a network. This includes making decisions such as: deciding when to accept new TRAFFIC, when to delete packets and when to adjust the ROUTING policies used in a network.

Network congestion is somewhat analogues to road congestion. One technique that has been used with some success to deal with road congestion is monitoring, in which rate of vehicles entering a road or area is restricted by signals.

The area of Internet congestion control was baptised in 1986-1987 when the then ARPANET suffered ‘congestion collapse’. Congestion collapse had been predicted by Nagel [89] in 1984. Congestion collapse occurs when mounting levels of traffic result in high packet loss inside the network, such that few or no packets are actually delivered to their destination, yet each link is highly loaded.

Various techniques have likewise been developed in attempt to minimize congestion collapse in communications networks.

1) Load control mechanisms

When the capacity available is less than the demand for capacity, load control is the critical element which determines how many packets are allowed onto each link of the network, who gets to send them and when.

At one end of the spectrum are the connection admission control (CAC) schemes, such as the Resource Reservation Protocol (RSVP) [4]. Such schemes require the network to maintain information about each connection and arbitrate whether connections are admitted or rejected so that the connections that are admitted can be absolutely guaranteed their required bandwidth for the duration of the connection. When the load of requested connections is increased beyond the capacity of the network then some new users will be rejected in order to maintain the bandwidth guarantees made to already admit users. CAC is good for honoring bandwidth supply contracts that specify minimum rates.

2) Rethinking Best-Effort Networks

To introduce Kelly’s framework for describing best-effort networks, we will provide an example of how bandwidth allocation in a best effort network compares to bandwidth allocation in a CAC network. Let us consider an example where there are three users each requesting a 1 Mb/s connection across the same 2 Mb/s link. In a CAC network, one user will have to miss out. However, the best-effort network makes this situation less rigid by making the users’ demand for bandwidth elastic. When users do not need strict guarantees of minimum bandwidth then blocking one user is not necessarily the best solution possible. Let us assume that a user is able to quantify, by a single number, its perceived quality of service (QoS) value of sending at a certain rate. Say, transmitting at a rate of 1 Mb/s gives the maximum possible user perceived QoS value, but transmitting at a rate of less than 1 Mb/s still gives some, but less, QoS value to the user. Then, it is possible to conceive of a solution, where by making the three users transmit at 2/3 Mb/s each, the sum of the perceived QoS values of all three users is greater than the sum if only two users are allowed to transmit at the maximum 1 Mb/s and one user is blocked. In such a system, where the user demand has some flexibility, it is possible to achieve a compromise solution for sharing the available capacity which is better for the QoS of the whole community of users, despite giving less capacity to some users. This is exactly the solution that the best-effort network achieves.

3) Supply Demand Pricing

Fix the price as pay per bit.

4) Differentiated Bandwidth

Differentiate bandwidth according to the demand and price rule. More demand more price less demand less price.

How Internet Works

 

One of the greatest things about the Internet is that nobody really owns it. It is a global collection of networks, both big and small. These networks connect together in many different ways to form the single entity that we know as the Internet. In fact, the very name comes from this idea of interconnected networks.

Since its beginning in 1969, the Internet has grown from four host computer systems to tens of millions. However, just because nobody owns the Internet, it doesn't mean it is not monitored and maintained in different ways. The Internet Society, a non-profit group established in 1992, oversees the formation of the policies and protocols that define how we use and interact with the Internet.

The Internet: Computer Network Hierarchy

Every computer that is connected to the Internet is part of a network, even the one in your home. For example, you may use a modem and dial a local number to connect to an Internet Service Provider (ISP). At work, you may be part of a local area network (LAN), but you most likely still connect to the Internet using an ISP that your company has contracted with. When you connect to your ISP, you become part of their network. The ISP may then connect to a larger network and become part of their network. The Internet is simply a network of networks.

Most large communications companies have their own dedicated backbones connecting various regions. In each region, the company has a Point of Presence (POP). The POP is a place for local users to access the company's network, often through a local phone number or dedicated line. The amazing thing here is that there is no overall controlling network. Instead, there are several high-level networks connecting to each other through Network Access Points or NAPs.

When you connect to the Internet, your computer
becomes part of a network.

Multipurpose Internet Mail Extensions

GxTechno Tags: mime types, mime, smtp, protocol

MIME (Multipurpose Internet Mail Extensions) is an Internet standard for describes message content types.

MIME is a standard for describing different types of information This was originally meant to be used to specify encoding for different types of information into text. This made it possible to send them as e-mail.

The standard MIME is also used in other types of communication where there is a need for specifying which type of information is used. This could be your local operating system or a web server.

MIME defines mechanisms for sending other kinds of information in e-mail. These include text in languages other than English using character encodings other than ASCII, and 8-bit binary content such as files containing images, sounds, movies, and computer programs. MIME is also a fundamental component of communication protocols such as HTTP, which requires that data be transmitted in the context of e-mail-like messages even though the data might not (and usually doesn't) actually have anything to do with e-mail. Mapping messages into and out of MIME format is typically done automatically by an e-mail client or by mail servers when sending or receiving Internet (SMTP/MIME) e-mail.

How do I read MIME in my mail?

Mime is just a specification. Normally the information is encoded with some other standard format. When decoded it regains it original shape.

To be able to read the file you need an application that can handle the attached file. If two files, a word document and a image is sent by email they would both get encoded as mime. Upon receiving these files there need to be an application associated with each file type. Microsoft word or maybe another word processor would be associated with the word document making it possible to read the file. Photoshop or another image viewer would be associated with the image.

Normally the conversion from MIME to files is handled by the e-mail application. When the file is stored on disk it is up to the operating system to map an application to file type.

MIME messages can contain text, images, audio, video, and other application-specific data.

Official MIME info is provided by the Internet Engineering Task Force (IETF) in the following documents:

• RFC-822   Standard for ARPA Internet text messages
• RFC-2045 MIME Part 1: Format of Internet Message Bodies
• RFC-2046 MIME Part 2: Media Types
• RFC-2047 MIME Part 3: Header Extensions for Non-ASCII Text
• RFC-2048 MIME Part 4: Registration Procedures
• RFC-2049 MIME Part 5: Conformance Criteria and Examples

Different applications support different MIME types.

The reference below is a list of MIME types supported by Microsoft Internet Information Server version 5.

---

MIME Types

MIME Types (Application):

Type/sub-type	Extension
application/envoy	evy
application/fractals	fif
application/futuresplash	spl
application/hta	hta
application/internet-property-stream	acx
application/mac-binhex40	hqx
application/msword	doc
application/msword	dot
application/octet-stream	*
application/octet-stream	bin
application/octet-stream	class
application/octet-stream	dms
application/octet-stream	exe
application/octet-stream	lha
application/octet-stream	lzh
application/oda	oda
application/olescript	axs
application/pdf	pdf
application/pics-rules	prf
application/pkcs10	p10
application/pkix-crl	crl
application/postscript	ai
application/postscript	eps
application/postscript	ps
application/rtf	rtf
application/set-payment-initiation	setpay
application/set-registration-initiation	setreg
application/vnd.ms-excel	xla
application/vnd.ms-excel	xlc
application/vnd.ms-excel	xlm
application/vnd.ms-excel	xls
application/vnd.ms-excel	xlt
application/vnd.ms-excel	xlw
application/vnd.ms-outlook	msg
application/vnd.ms-pkicertstore	sst
application/vnd.ms-pkiseccat	cat
application/vnd.ms-pkistl	stl
application/vnd.ms-powerpoint	pot
application/vnd.ms-powerpoint	pps
application/vnd.ms-powerpoint	ppt
application/vnd.ms-project	mpp
application/vnd.ms-works	wcm
application/vnd.ms-works	wdb
application/vnd.ms-works	wks
application/vnd.ms-works	wps
application/winhlp	hlp
application/x-bcpio	bcpio
application/x-cdf	cdf
application/x-compress	z
application/x-compressed	tgz
application/x-cpio	cpio
application/x-csh	csh
application/x-director	dcr
application/x-director	dir
application/x-director	dxr
application/x-dvi	dvi
application/x-gtar	gtar
application/x-gzip	gz
application/x-hdf	hdf
application/x-internet-signup	ins
application/x-internet-signup	isp
application/x-iphone	iii
application/x-javascript	js
application/x-latex	latex
application/x-msaccess	mdb
application/x-mscardfile	crd
application/x-msclip	clp
application/x-msdownload	dll
application/x-msmediaview	m13
application/x-msmediaview	m14
application/x-msmediaview	mvb
application/x-msmetafile	wmf
application/x-msmoney	mny
application/x-mspublisher	pub
application/x-msschedule	scd
application/x-msterminal	trm
application/x-mswrite	wri
application/x-netcdf	cdf
application/x-netcdf	nc
application/x-perfmon	pma
application/x-perfmon	pmc
application/x-perfmon	pml
application/x-perfmon	pmr
application/x-perfmon	pmw
application/x-pkcs12	p12
application/x-pkcs12	pfx
application/x-pkcs7-certificates	p7b
application/x-pkcs7-certificates	spc
application/x-pkcs7-certreqresp	p7r
application/x-pkcs7-mime	p7c
application/x-pkcs7-mime	p7m
application/x-pkcs7-signature	p7s
application/x-sh	sh
application/x-shar	shar
application/x-shockwave-flash	swf
application/x-stuffit	sit
application/x-sv4cpio	sv4cpio
application/x-sv4crc	sv4crc
application/x-tar	tar
application/x-tcl	tcl
application/x-tex	tex
application/x-texinfo	texi
application/x-texinfo	texinfo
application/x-troff	roff
application/x-troff	t
application/x-troff	tr
application/x-troff-man	man
application/x-troff-me	me
application/x-troff-ms	ms
application/x-ustar	ustar
application/x-wais-source	src
application/x-x509-ca-cert	cer
application/x-x509-ca-cert	crt
application/x-x509-ca-cert	der
application/ynd.ms-pkipko	pko
application/zip	zip

MIME Types (Audio):

Type/sub-type	Extension
audio/basic	au
audio/basic	snd
audio/mid	mid
audio/mid	rmi
audio/mpeg	mp3
audio/x-aiff	aif
audio/x-aiff	aifc
audio/x-aiff	aiff
audio/x-mpegurl	m3u
audio/x-pn-realaudio	ra
audio/x-pn-realaudio	ram
audio/x-wav	wav

MIME Types (Image):

Type/sub-type	Extension
image/bmp	bmp
image/cis-cod	cod
image/gif	gif
image/ief	ief
image/jpeg	jpe
image/jpeg	jpeg
image/jpeg	jpg
image/pipeg	jfif
image/svg+xml	svg
image/tiff	tif
image/tiff	tiff
image/x-cmu-raster	ras
image/x-cmx	cmx
image/x-icon	ico
image/x-portable-anymap	pnm
image/x-portable-bitmap	pbm
image/x-portable-graymap	pgm
image/x-portable-pixmap	ppm
image/x-rgb	rgb
image/x-xbitmap	xbm
image/x-xpixmap	xpm
image/x-xwindowdump	xwd

MIME Types (Message):

Type/sub-type	Extension
message/rfc822	mht
message/rfc822	mhtml
message/rfc822	nws

MIME Types (Text):

Type/sub-type	Extension
text/css	css
text/h323	323
text/html	htm
text/html	html
text/html	stm
text/iuls	uls
text/plain	bas
text/plain	c
text/plain	h
text/plain	txt
text/richtext	rtx
text/scriptlet	sct
text/tab-separated-values	tsv
text/webviewhtml	htt
text/x-component	htc
text/x-setext	etx
text/x-vcard	vcf

MIME Types (Video):

Type/sub-type	Extension
video/mpeg	mp2
video/mpeg	mpa
video/mpeg	mpe
video/mpeg	mpeg
video/mpeg	mpg
video/mpeg	mpv2
video/quicktime	mov
video/quicktime	qt
video/x-la-asf	lsf
video/x-la-asf	lsx
video/x-ms-asf	asf
video/x-ms-asf	asr
video/x-ms-asf	asx
video/x-msvideo	avi
video/x-sgi-movie	movie

MIME Types (Video):

Type/sub-type	Extension
x-world/x-vrml	flr
x-world/x-vrml	vrml
x-world/x-vrml	wrl
x-world/x-vrml	wrz
x-world/x-vrml	xaf
x-world/x-vrml	xof

---

Mime Types By File Extension

Extension	Type/sub-type
	application/octet-stream
323	text/h323
acx	application/internet-property-stream
ai	application/postscript
aif	audio/x-aiff
aifc	audio/x-aiff
aiff	audio/x-aiff
asf	video/x-ms-asf
asr	video/x-ms-asf
asx	video/x-ms-asf
au	audio/basic
avi	video/x-msvideo
axs	application/olescript
bas	text/plain
bcpio	application/x-bcpio
bin	application/octet-stream
bmp	image/bmp
c	text/plain
cat	application/vnd.ms-pkiseccat
cdf	application/x-cdf
cer	application/x-x509-ca-cert
class	application/octet-stream
clp	application/x-msclip
cmx	image/x-cmx
cod	image/cis-cod
cpio	application/x-cpio
crd	application/x-mscardfile
crl	application/pkix-crl
crt	application/x-x509-ca-cert
csh	application/x-csh
css	text/css
dcr	application/x-director
der	application/x-x509-ca-cert
dir	application/x-director
dll	application/x-msdownload
dms	application/octet-stream
doc	application/msword
dot	application/msword
dvi	application/x-dvi
dxr	application/x-director
eps	application/postscript
etx	text/x-setext
evy	application/envoy
exe	application/octet-stream
fif	application/fractals
flr	x-world/x-vrml
gif	image/gif
gtar	application/x-gtar
gz	application/x-gzip
h	text/plain
hdf	application/x-hdf
hlp	application/winhlp
hqx	application/mac-binhex40
hta	application/hta
htc	text/x-component
htm	text/html
html	text/html
htt	text/webviewhtml
ico	image/x-icon
ief	image/ief
iii	application/x-iphone
ins	application/x-internet-signup
isp	application/x-internet-signup
jfif	image/pipeg
jpe	image/jpeg
jpeg	image/jpeg
jpg	image/jpeg
js	application/x-javascript
latex	application/x-latex
lha	application/octet-stream
lsf	video/x-la-asf
lsx	video/x-la-asf
lzh	application/octet-stream
m13	application/x-msmediaview
m14	application/x-msmediaview
m3u	audio/x-mpegurl
man	application/x-troff-man
mdb	application/x-msaccess
me	application/x-troff-me
mht	message/rfc822
mhtml	message/rfc822
mid	audio/mid
mny	application/x-msmoney
mov	video/quicktime
movie	video/x-sgi-movie
mp2	video/mpeg
mp3	audio/mpeg
mpa	video/mpeg
mpe	video/mpeg
mpeg	video/mpeg
mpg	video/mpeg
mpp	application/vnd.ms-project
mpv2	video/mpeg
ms	application/x-troff-ms
mvb	application/x-msmediaview
nws	message/rfc822
oda	application/oda
p10	application/pkcs10
p12	application/x-pkcs12
p7b	application/x-pkcs7-certificates
p7c	application/x-pkcs7-mime
p7m	application/x-pkcs7-mime
p7r	application/x-pkcs7-certreqresp
p7s	application/x-pkcs7-signature
pbm	image/x-portable-bitmap
pdf	application/pdf
pfx	application/x-pkcs12
pgm	image/x-portable-graymap
pko	application/ynd.ms-pkipko
pma	application/x-perfmon
pmc	application/x-perfmon
pml	application/x-perfmon
pmr	application/x-perfmon
pmw	application/x-perfmon
pnm	image/x-portable-anymap
pot,	application/vnd.ms-powerpoint
ppm	image/x-portable-pixmap
pps	application/vnd.ms-powerpoint
ppt	application/vnd.ms-powerpoint
prf	application/pics-rules
ps	application/postscript
pub	application/x-mspublisher
qt	video/quicktime
ra	audio/x-pn-realaudio
ram	audio/x-pn-realaudio
ras	image/x-cmu-raster
rgb	image/x-rgb
rmi	audio/mid
roff	application/x-troff
rtf	application/rtf
rtx	text/richtext
scd	application/x-msschedule
sct	text/scriptlet
setpay	application/set-payment-initiation
setreg	application/set-registration-initiation
sh	application/x-sh
shar	application/x-shar
sit	application/x-stuffit
snd	audio/basic
spc	application/x-pkcs7-certificates
spl	application/futuresplash
src	application/x-wais-source
sst	application/vnd.ms-pkicertstore
stl	application/vnd.ms-pkistl
stm	text/html
svg	image/svg+xml
sv4cpio	application/x-sv4cpio
sv4crc	application/x-sv4crc
swf	application/x-shockwave-flash
t	application/x-troff
tar	application/x-tar
tcl	application/x-tcl
tex	application/x-tex
texi	application/x-texinfo
texinfo	application/x-texinfo
tgz	application/x-compressed
tif	image/tiff
tiff	image/tiff
tr	application/x-troff
trm	application/x-msterminal
tsv	text/tab-separated-values
txt	text/plain
uls	text/iuls
ustar	application/x-ustar
vcf	text/x-vcard
vrml	x-world/x-vrml
wav	audio/x-wav
wcm	application/vnd.ms-works
wdb	application/vnd.ms-works
wks	application/vnd.ms-works
wmf	application/x-msmetafile
wps	application/vnd.ms-works
wri	application/x-mswrite
wrl	x-world/x-vrml
wrz	x-world/x-vrml
xaf	x-world/x-vrml
xbm	image/x-xbitmap
xla	application/vnd.ms-excel
xlc	application/vnd.ms-excel
xlm	application/vnd.ms-excel
xls	application/vnd.ms-excel
xlt	application/vnd.ms-excel
xlw	application/vnd.ms-excel
xof	x-world/x-vrml
xpm	image/x-xpixmap
xwd	image/x-xwindowdump
z	application/x-compress
zip	application/zip

MIME Technical Summary

MIME is defined by an Internet standard document called RFC1521. This document summarizes the contents of RFC1521. Sufficient detail is presented here to understand the capabilities of MIME. For sufficient detail to implement MIME please read RFC1521.

MIME allows messages to contain multiple objects. When multiple objects are in a MIME message, they are represented in a form called a body part. A body part has a header and a body, so it makes sense to speak about the body of a body part. Also, body parts can be nested in bodies that contain one or multiple body parts.

The Content-Type values, subtypes, and parameter names defined in the MIME standard are case-insensitive. However, many parameter values are case sensitive

The MIME standard is written to allow MIME to be extended in certain ways, without having to revise the standard. MIME specifies sets of values that are allowed for various fields and parameters. The provides a procedure for extending these sets of values by registering them with an entity called the Internet Assigned Numbers Authority (IANA).

Graph & Tree

GxTechno Tags: Computer Science, graph, graph traversal, graph representation, dfs, bfs

• A graph is a finite set of nodes with edges between nodes

• Formally, a graph G is a structure (V,E) consisting of

– a finite set V called the set of nodes, and

– a set E that is a subset of VxV. That is, E is a set of pairs of the form (x,y) where x and y are nodes in V

Graph Representation

• For graphs to be computationally useful, they have to be conveniently represented in programs

• There are two computer representations of graphs:

– Adjacency matrix representation

– Adjacency lists representation

Adjacency Matrix Representation

• In this representation, each graph of n nodes is represented by an n x n matrix A, that is, a two-dimensional array A

• The nodes are (re)-labeled 1,2,…,n

• A[i][j] = 1 if (i,j) is an edge

• A[i][j] = 0 if (i,j) is not an edge

Pros and Cons of Adjacency Matrices

• Pros:

– Simple to implement

– Easy and fast to tell if a pair (i,j) is an edge: simply check if A[i][j] is 1 or 0

• Cons:

– No matter how few edges the graph has, the matrix takes O(n2) in memory

Adjacency Lists Representation

• A graph of n nodes is represented by a one-dimensional array L of linked lists, where

– L[i] is the linked list containing all the nodes adjacent from node i.

– The nodes in the list L[i] are in no particular order

Pros and Cons of Adjacency Lists

• Pros:

– Saves on space (memory): the representation takes as many memory words as there are nodes and edge.

• Cons:

– It can take up to O(n) time to determine if a pair of nodes (i,j) is an edge: one would have to search the linked list L[i], which takes time proportional to the length of L[i].

Graph Traversal Techniques

• The previous connectivity problem, as well as many other graph problems, can be solved using graph traversal techniques

• There are two standard graph traversal techniques:

– Depth-First Search (DFS)

– Breadth-First Search (BFS)

• In both DFS and BFS, the nodes of the undirected graph are visited in a systematic manner so that every node is visited exactly one.

• Both BFS and DFS give rise to a tree:

– When a node x is visited, it is labeled as visited, and it is added to the tree

– If the traversal got to node x from node y, y is viewed as the parent of x, and x a child of y

Depth-First Search

• DFS follows the following rules:

1. Select an unvisited node x, visit it, and treat as the current node

2. Find an unvisited neighbor of the current node, visit it, and make it the new current node;

3. If the current node has no unvisited neighbors, backtrack to the its parent, and make that parent the new current node;

4. Repeat steps 3 and 4 until no more nodes can be visited.

5. If there are still unvisited nodes, repeat from step 1.

Implementation of DFS

• Observations:

– the last node visited is the first node from which to proceed.

– Also, the backtracking proceeds on the basis of "last visited, first to backtrack too".

– This suggests that a stack is the proper data structure to remember the current node and how to backtrack.

Breadth-First Search

• BFS follows the following rules:

1. Select an unvisited node x, visit it, have it be the root in a BFS tree being formed. Its level is called the current level.

2. From each node z in the current level, in the order in which the level nodes were visited, visit all the unvisited neighbors of z. The newly visited nodes from this level form a new level that becomes the next current level.

3. Repeat step 2 until no more nodes can be visited.

4. If there are still unvisited nodes, repeat from Step 1.

Implementation of DFS

• Observations:

– the first node visited in each level is the first node from which to proceed to visit new nodes.

• This suggests that a queue is the proper data structure to remember the order of the steps.

WAP for paramid pattern-2

Write a program to display the pattern:

Output:-

1234554321

1234 4321

123 321

12 21

1 1

Solution:-

#include

#include

void main()

{

int i,j,k,m=0;

for(i=5;i>=1;i--)

{

for(j=1;j<=i;j++)

{

printf(“%d”,j);

}

for(k=1;k<=m;k++)

{

printf(“ “);

}

for(j=i;j>=1;j--)

{

printf(“%d”,j);

}

printf(“\n”);

m=m+2;

}

getch();

}

WAP to generate the peramid pattern

Write a program to generate the following pattern:

Output:-

1
121
12321
1234321
123454321

Solution:-

#include
#include

void main()
{
int i,j;
for (i=1;i<=5;i++) { for(j=4;j>=i;j--)
{
printf(" ");
}

for(j=1;j<=i;j++) { printf("%d",j); } printf("\n"); } getch(); }