An algorithm is a set of instructions for solving a problem or performing a task.
Operating systems would not exist without the use of algorithms.
OS: the glue between digital bytes and the user
without it, we’d all still be using typewriters
OS’s take many forms depending on their intended use
Most researchers agree:
Origins of the OS lie in our earliest history: not the last few decades
Original OS Examples
(both intended to keep precise records of complex data)
Modern computers didn’t appear until mid 20th century
1970’s and 80’s:
they became more widely used in academia
able to talk to one another
microprocessor tech evolved enough for creation of powerful desktop computers
1980’s and 90’s:
the familiar user-friendly OS emerged
Microsoft and Apple drove the evolution of the desktop GUI OS
their battle has given us a wide variety of OS’s
Without algorithms, there would be no World Wide Web
Two of the most famous, world changing algorithms:
TCP/IP (Transmission Control Protocol/Internet Protocol)
Defines how the Internet transmits data
Invented when computers were mainframes housed in cool rooms (and dinosaurs roamed the earth)
HTTP (Hypertext Transfer (or Transport) Protocol
underlies the WWW and played a large part in the Internet’s mid-90s breakthrough
1969: ARPANET was developed
a four-node, packet-switched network
1974: TCP/IP was developed
proposed as the new set of protocols
“The most basic bit of ‘science’ in current networks is the discovery that packet switching actually works,” MIT’s Clark told the E-Commerce Times.
Many thought TCP/IP would not work: they thought it would be unstable.
1980: ARPA began converting its computers to TCP/IP
1983: ARPA mandated that all computers connected to ARPNET, use TCP/IP
TCP/IP became the standard underpinning today’s Internet – used by hundreds of millions worldwide
there are nearly 150,000,000 active Web sites on the Internet today
Google’s search engine which defines the way in which millions of people find information online
What does it do?
Searches the Web using for keywords used to search
Assigns a page rank to each page based on several factors
ie. How many times keywords appear on the page
Higher ranked pages appear further up in Google’s search engine results page (SERP)
Being listed prominently on Google can result in a big boost in site traffic and visibility
How does it work?
Automated programs called spiders or crawlers travel the Web
Spiders move from link to link building up an index page for keywords
Google references the index when a user enters a search query
1998: 10,000 Google searches/day
1999: 500,000 Google searches/day
Google no longer shares those numbers
estimates 3B daily searches
1998: First Google index had 26m Web pages
2011: Over 1trillion
Google may have a googol worth of pages in just a few years
1998: Bill Gates told Auletta his greatest fear was of a few guys in a garage starting a behemoth that would challenge his company.
That’s precisely how Google started
Google revolutionized the media world
It stores 24 quadrillion data bits
Plans to digitize 20 million books
Sat navs are a fascinating offshoot of both the US military’s desire to equip its units with the facility to find out their position and the ability to display maps on a computer screen.
2 major algorithms for sat-navs.
the ability of the unit to use the GPS satellites to work out where the unit is situated
the ability of the sat-nav to determine the shortest distance from point A to point B
Other algorithms in play, mostly dealing with the visual display of the route to take, but these two algorithms are the most important.
GPS started out as a US Air Force system to help determine the position of any receiver to an accuracy of 15 metres.
Regan promised to make GPS available for civilian use following the downing of the civilian KAL 007 airliner
the airliner had drifted into Soviet restricted airspace
1993 – the unencrypted civilian signal was downgraded for accuracy of about 100 meters.
2000 – accuracy limitation was removed
30 satellites, in Earth’s orbit, transmit the same information
Three main pieces of data:
exact time of transmital
precise orbital data (the ephemeris)
overall system health
The GPS unit listens for, and interprets, these messages
The GPS unit uses time and the speed of light to calculate location
GPS units have become prevalent throughout our society
hand-held GPS devices
Sometimes, algorithms that change the world arise not as research for its own sake, but to answer a pressing need. One example is encryption.
Encryption was created to defend against code-breakers
Code-breakers seek to steal or eavesdrop on vital data
1960’s – standards-based multi-vendor networks were created
1977 – encryption algorithm, RSA, evolved to safeguard code
RSA – named after inventors Rivest, Shamir and Adleman
RSA and it’s descendants play a critical role in today’s Internet-heavy environment
CIS (Cryptographic Interoperability Strategy)
developed to increase assured rapid sharing within the US and between allies
Common public standards, protocols, algorithms and modes are used
These are known as the “Secure Sharing Suite”or S.3.
Implementation of CIS facilitates the development of broader secure cryptographic products
Provides war fighters on the battlefield, ability to share time-sensitive info securely
Enables the gov’t to share intelligence info securely with State and local First Responders
NSA Suite A Cryptography: Unpublished algorithm
Suite A contains both classified and unclassified algorithms
Used in applications where Suite B may not be appropriate
NSA Suite B Cryptography: Published algorithm
Includes cryptographic algorithms for:
These algorithms play a huge role in keeping our country secure
Algorithms have the power to change the course of history
They can be found everywhere you look
Linking structure on the Web
Inner workings of automobiles
Intricacies of stock market exchanges
Whatever the purpose, algorithms will continue to shake up the status quo
The key is to recognize which algorithms will drive the directions of tomorrow’s business world