Web Technology I

Composition of search sites

1)One spider, which crawls across the Internet gathering information; 2)a database, which contains all the information the spiders gather; 3) a search tool, which people use to search through the database.

Content Related Specialists

1)the Information Architect (IA) 2 the Content Strategist

What is grid computing?

A collection of computers, often geographically dispersed, that are coordinated to solve a common problem. the largest and best-known so far is the Search for Extraterrestrial Intelligence project (SETI@home), overseen by the University of California, Berkeley.

dial-up modem

A communication device that converts a computer's digital signals into analog signals before transmission over telephone lines. When you use a modem to connect we dial in to Internet service provider ISP which means you are connecting to a modem attached to a more powerful computer called a server. Modems are controlled by your computer and communications software by a set of commands called the AT command set

Connection between API's and web services?

All web services can be APIs, but not all APIs can be web services.

Fiber-optic cable

Cable that uses light guided through thin glass tubes, instead of electrical signals, to transmit data. It is very fast but also expensive. They do this using IPTV, which uses the Internet's underlying protocols to deliver TV.

Client Pull

Client pull is executed by the Refresh command. A refresh command is written into an HTML document using the tag. The contents of the tag are added to the header's meta-information that the server sends along with the HTTP response. During a client pull sequence, the browser reads this header information that instructs it to use your PC's internal clock to keep track of the time elapsed between pages retrieved. When the time has elapsed, the browser requests and displays the next page. Each page in a client pull sequence can be located anywhere on the Web. The URL following the Refresh command might lead the browser to any active server. Page E is located on a different server than pages AD, but is still requested automatically after five seconds.

What are name servers?

Computers that are responsible for keeping track of such changes and translating them between IP addresses and domain addresses. The Internet can't understand alphanumeric Internet addresses so name servers translate those addresses into their proper numeric IP addresses.

What is CMS used for?

Content Management Systems are used to make content changers easier and available with basic technical skills.

Flash

Flash is an animation program that enables designers to add animation, sound, and interactivity to web pages. Flash uses vector graphics instead of bit-mapped graphics. Vector graphics are mathematical descriptions of a shape, while a bitmappedimage is an actual pixel-by-pixel representation of the image. Not only are vector graphics smaller and more suitable to the Web because of reduced download time than bit-mapped images, but, unlike bit-mapped graphics, they can also be zoomed in on without any degradation in quality.

Full Stack Development

Full-stack devs take care of both the front-end and the back-end, and need to know how the web works on all levels, in order to determine how the client and server-sides will relate.

Gateways

Gateways are similar to bridges, but they also translate data from one type of network to another.

What does an IP address do?

IP address defines your location on the network

What does Web development usually refer to among Web Developers?

Main non-design aspects of building Web sites: - writing markup and - coding.

How does MapQuest work?

MapQuest, for example, uses a simple, basic HTML interface, and concentrates on directions and maps.

What are the most popular streaming technologies?

RealPlayer Other kinds of streaming technologies exist, such as that used by the Windows Media Player. However, all streaming technologies work similarly

How are web pages created?

Pages on the Web are built using a markup language called Hypertext Markup Language (HTML). The language contains commands that tell your browser how to display text, graphics, and multimedia files. It also contains commands for linking the page to other pages and to other Internet resources.

What is peer to peer technology?

Peer to Peer Tech enables people to share files directly with one another

Image Maps

Image maps are static images that have been divided into sections, each of which contains a link.

What is a Multicast Backbone?

The MBone (Multicast Backbone) is a high-speed Internet backbone capable of sending live video and audio broadcasts. It's a network of host computers that communicate with one another using a technique called IP (Internet Protocol) Multicast. An MBone multicast begins when a video signal is digitized and compressed so that it can be sent over the Internet. Without compression, the signal would be too large and take too long to deliver.

Information architecture

is the set of ideas about how all information in a given context should be organized. An Information Architect (also called an Information Designer) organizes the content logically and for ease of findability. They may be responsible for 1) search functionality, 2)site diagrams, 3) and how the content and data are organized on the server. Information architecture is inevitably entwined with UX and UI design (defined shortly) as well as content management. If you like organizing or are gaga for taxonomies, information architecture may be the job for you.

Cons of DSL connection

it requires that your house (and DSL modem) be located within a certain distance from the telephone company office and its DSL modem.

What are the essential functions of web services?

- Available over the internet or intranet networks -Standardized XML messaging system -Independent of a single operating system or programming language -Self-describing via standard XML language -Discoverable through a simple location method

What does front end dev take care of?

- layout, - implementing design - interactivity using HTML, CSS and JavaScript.

Types of MarkUp Languages

-HTML -Dynamic HTML (Allows HTML to be more than a static language. They enable HTML to perform animations and become more interactive and flexible.) -The Extended Markup Language (XML) (It separates the content of a page from its presentation. It tags different types of content and then has other technologies such as templates and style sheets determine how that content should look.

What are the benefits of web services?

-The technology helps IT pros and web architects streamline connectivity by minimizing development time. -This simplified infrastructure, company executives begin to see higher ROI (return on investment). -In a B2B operation where both parties understand how the process works, web services provide efficient technology distribution throughout an entire network.

What type of IP adresses do we have?

-a static address - a dynamic address

Ways a computer connects to the Internet

-dial-in connections to LANs (local area networks) -wireless connections to connections over cable TV wires - DSL connections that use phone wires but connect you at high speed.

What are the organizational structures that websites use?

-tree structure, a pyramid or an outline format enables users to easily navigate through the site and find the information they want. -linear structure, one page leads to the next, which then leads to the next, and so on, in a straight line. -random structure, pages are connected to one another seemingly at random.

Online sound formats

.wav, .mp3, or .au. To play these files, you first have to download them and also download audio-player software to play them on your computer. Every new computer sold has this software already built in, such as Windows Media Player, iTunes, RealPlayer, or Musicmatch Jukebox.

What does a website need?

1) a host (The host manages the communications protocols and houses the pages and the related software required to create a website on the Internet. The host machine often uses the Unix, Windows, Linux, or Macintosh operating systems, which have the TCP/IP protocols built in.) 2) a computer 3) server software that runs on the host.(The server software resides on the host and serves up the pages and otherwise acts on the requests sent from the client browser software. The server software is not responsible for TCP/IP communicationsthe host operating system does thatbut instead the server software handles the HTTP requests and communications with the host operating system.)

What are the most popular soulutions to finding information on the Internet?

1)Indexes present a highly structured way to find information. They enable you to browse through information by categories, such as arts, computers, entertainment, sports, and so on. 2)Search engines are essentially massive databases that cover wide swaths of the Internet. Search engines don't present information in a hierarchical fashion. Instead, you search through them as you would a database, by typing keywords that describe the information you want. (Many search engines now also include indexes as well as search tools, but they are primarily used for searching.

Virtual Reality Modeling Language (VRML).

A programming language that allows the creation and display of three-dimensional objects on a computer screen and allows users to have the illusion of moving around the objects. This language instructs computers on how to build 3D geometric objects. Programmers and artists use the language to build complex worlds from these geometric objects. A VRML world is created by an ASCII text file containing VRML language commandsand for greater realism, graphics files can be added to this world as well.

Ajax

A programming methodology that uses a number of existing technologies together and enables Web applications to make incremental updates to the user interface without the need to reload the browser page.

How do routers send data to its destination?

A router has input ports for receiving IP packets and output ports for sending those packets toward their destinations. When a packet comes to an input port, the router examines the packet header and checks the destination in it against a routing tablea database that tells the router how to send packets to various destinations.

What is a URL? (Uniform Resource Locator)

A specific location on the internet.

What is a wiki?

A wiki is a website that lets groups of people work together to create and edit bits of information, and then lets anyone who visits the wiki view that information.

How to access the Internet via Satelite Connection?

Accessing the Internet via a satellite connection delivers information to your computer at much higher speeds than do normal modemsat 400 Kbps. To use it, you need a satellite dish on your home in the same way that you need a satellite dish to get satellite TV.

Static IP address

An IP address that is manually assigned to a device and remains constant until it is manually changed.

broadband connection

An Internet connection such as DSL or cable modem that offers higher bandwidth, and therefore faster transmission speed, than standard modem connections.

dynamic IP address

An assigned IP address that is used for the current session only. When the session is terminated, the IP address is returned to the list of available addresses and it is usually assignes by ISP.

How does Google Maps work?

Google Maps uses a far more interactive interface that allows visitors to more easily zoom in and zoom out, switch to a satellite view, and navigate through maps by dragging with a mouse. Google Maps does this by using a technique called AJAX. Google also offers a tool more sophisticated than mere maps, Google Earth. Google Earth lets you "fly" to any location on earth in a virtual tour, using high-resolution photos and animations.

Hubs

Hubs are important because they link groups of computers to one another and let computers communicate with each other.

Domain Name System (DNS)

Internet service that translates domain names into IP addresses. It is the way in which computers can contact each other and do things such as exchange email or display web pages. The DNS translates the plain English address into a series of numbers called an IP (for Internet Protocol) address.

How does BitTorrent work?

It downloads bits and pieces of the requested file from multiple computers, and then assembles them into one file after it receives all the pieces. To use BitTorrent, you first need to download and install a client piece of software. BitTorrent clients are free, and available from many places on the Internet

What is Wikipedia?

It is a website where anyone can create a page or wiki about something. The Wikipedia is an huge online encyclopedia that anyone can use and edit. As of this writing, versions of the Wikipedia are available in ten languages with the English version alone having more than one million entries and constantly growing. Anyone can create or edit an entry in the Wikipedia; it depends on a kind of vast communal intelligence to be sure that no errors are made or introduced into it. Volunteers constantly check it for errors and many people with special interests monitor entries to be sure that the Wikipedia stays accurate.

Hayes command set

It's a language that instructs the modem on what to do at various points during a communications session, such as opening up a line and sending out tones that the telephone system can understand.

Cons of dial up connection

It's too slow to be of much use. Websites use many graphics and multimedia features, and dial-up connections are so slow that the Web can seem unusable.

How do Map sites work?

Map sites like MapQuest and Google Maps do not create their own maps. Instead, they buy maps and map databases from another company. One of the main providers of map data to map sites is the U.S.-based company Navteq

How MP3 music files work?

One of the most popular ways to distribute music on the Internet is through the use of MP3 music files. The files use special algorithms that shrink the size of the files while retaining CD-like quality. Before MP3 files can be posted, however, the music has to be recorded. The music is recorded no differently than any other kind of music and is then put on a CD.

How does podcasting work?

Podcasts can be created by anyone, and can be as simple as a person talking into a microphone on his PC, or as sophisticated as a high-quality news or music show. First, the podcast is recorded. An individual can record it with a microphone attached to his computer, or the show can be recorded in a professional studio.

REST

REST, provides communication and connectivity between devices and the internet for API-based tasks. Most RESTful services use HTTP as the supporting protocol.

SOAP

SOAP, is an XML-based Web service protocol to exchange data and documents over HTTP or SMTP (Simple Mail Transfer Protocol). It allows independent processes operating on disparate systems to communicate using XML.

routing table division

Static routing tables (The static table is simpler, and specifies specific paths for packets to use to get to their final destination.) Dynamic routing tables (The dynamic table allows a packet to have multiple routes to get to its destination.)

How is the Web built?

The Web operates on a client/server model. You run web client browser software, such as Netscape Navigator or Microsoft's Internet Explorer, on your computer. That client contacts a web server and requests information or resources. The web server locates and then sends the information to the web browser, which displays the results.

How does Wikipedia work?

The Wikipedia is so popular and visited so frequently that it needs to be hosted on literally hundreds of servers all over the world, including in the United States, France, Amsterdam, and Korea.

What does backend dev do?

The backend dev uses computer programmes to ensure that the server, the application and the database run smoothly together. This type of dev need to analyse what a company's needs are and provide efficient programming solutions. To do all this amazing stuff they use a variety of server-side languages, like PHP, Ruby, Python and Java.

How does the link between a website and a database work?

The database can take just about any form and can be as simple as a FileMaker Pro database or as complex as an Oracle SQL database. A variety of technologies bridge websites and databases, including Perl, .NET, Common Gateway Interface (CGI), and others. On the client side of the database, you see a web page that includes a form in which you enter your search terms. When you execute the search, the web server passes your search information to a CGI script, which then searches the database.

Web services and .NET differences

The difference is in how the actual applications are written and run. Web services are typically written in Java, and can be run in any browser that has Java capabilities.

How does Shockwave work?

The first step in a Shockwave animation happens in a multimediaauthoring program such as Director or Authorware. An animation designer must gather the raw materials, such as still images, music, and sound effects, necessary for a short and compelling animation.

How home networks work?

The main reason people set up home networks is to share highspeed Internet access, such as via a cable modem or DSL modem, among several computers. To give the home network access to the Internet, an Ethernet cable runs from the cable modem or DSL modem to the networking device, called a router.

How do cell phones access the Internet?

The main way cellular telephones access the Internet is through a protocol called the Wireless Access Protocol (WAP) and its associated markup language, the Wireless Markup Language (WML). To use WAP to access a web page with a cellular telephone, you first need to make a cellular phone call. When you dial a cell phone, it looks for the nearest cellular antenna, called a base station, to transmit the call. The phone scans nearby base stations and locks on one that is either the closest or has the most powerful signal.

What is the benefit of using Google?

The secret to Google's speed and accuracy are the algorithms it uses when it searches. It uses many factors to determine which are the most relevant pages that match your search, including how popular the page is, where the search term is found within the page, and similar rules. Google's breakthrough was that it doesn't stop at only considering the page's popularity. It also looks at the quality of pages that link to that page. So if there are many well-regarded popular pages that link to a site, that site will be considered more important than a site that has lessimportant, less-popular pages linking to it.

What is the server?

The server (also known as the host) is usually a more powerful computer that houses the data and/or server software

Why are website links to database useful?

The web page becomes the front-end for database applications, enabling you to select search criteria and execute even complex searches of a database that resides on the host computer.

What is a Web Service?

The web service itself is a piece of software written in a language such as Java, and that can be found and run over the Internet using these protocols and technologies.

Types of Web Services?

There are a few central types of web services: ● XML-RPC, ● UDDI, ● SOAP, ● REST

What are routers for and what do they do?

They ensure that all data gets sent to where it's supposed to go via the most efficient route. Routers open the IP packets of data to read the destination address, calculate the best route, and then send the packet toward its final destination.

TCP

Transmission Control Protocol (TCP)the language computers use when communicating over the Internetfirst breaks the information up into packets, smaller blocks of information that also contain a variety of data that helps the packets travel across the Internet.

How Internet Radio Broadcasting Works

Two main types of radio stations broadcast over the Internettraditional radio stations that also broadcast over the airwaves, as well as Internet-only broadcasts. In both instances, the radio station plays music, news, or offers other kinds of broadcasts in much the same way that a normal radio station does.

UDDI

UDDI (Universal Description, Discovery, and Integration) is an XML-based standard for detailing, publishing, and discovering web services. It's basically an internet registry for businesses around the world. The goal is to streamline digital transactions and e-commerce among company systems.

How does a web browser work?

Web browsers consist of client software that runs on your computer and displays home pages on the Web. There are clients for a wide variety of devices, including Windows, Macintosh, and Unix computers.

List of tasks to which Web development commonly refers

Web engineering, - Web design, - Web content development, - client liaison, - client-side/server-side scripting, - Web server and network security configuration, - and e-commerce development.

Explain .NET and Web services

Web services and .NET allow programs or services to be run remotely across the Internet, using a web browser. First the program, service, or applet that will be run in .NET or as a web service needs to be created. For a web service, the service is frequently written in Java. For .NET, it is generally written using a development platform called Visual Studio .NET, which allows developers to use a variety of languages, including Microsoft's Visual Basic .NET, C++ .NET, and Visual C# .NET. After it is written, it is posted to an application server, which will deliver it when requested. The site hosting the service is commonly called a service provider.

How is virtual reality created by VRML?

When someone wants to create a virtual world, she uses the Virtual Reality Modeling Language (VRML). VRML lets people create 3D worlds not by drawing them, but instead by using the VRML computer language to describe the geometry of a scene. VRML files are much smaller than graphics files. VRML files are simply text files containing instructions for drawing the VRML world. VRML files end in a .wrl extension. After the world is created, it is posted on a web server.

How does an iPod work?

When you load music into your iPod from your computer, it's stored on iPod's hard disk in MP3 or Advanced Audio Code (AAC) format. Both formats compress the original music so the files don't take up too much space. Stored along with each file is metadata that contains information about it, such as the artist name, album name, music category, and so on. This allows you to easily categorize and find music you want to play. The number of songs you can store on an iPod varies according to the hard disk size and how much each song has been compressed. With typical compression using the AAC format, you can store about 10,000 songs on a conventional iPod's 40GB hard disk

How does Google search the Internet?

When you search using Google, you're actually searching through an index of web pages. To gather the raw material for the index, Google's web-crawling robot, called Googlebot, sends a requests to a web server for a web page. It then downloads the page. Googlebot runs on many computers simultaneously, and constantly requests and receives web pages, making thousands of requests per second. In fact, Googlebot makes requests more slowly than its full capability, because if it operated fullthrottle, it would overwhelm many web servers, and the servers would not be able to deliver pages quickly enough to users.

How RealPlayer Streaming Audio Works

When you use your web browser and click a link to a RealPlayer sound clip on a home page, the link doesn't lead directly to a sound file. Instead, your web browser contacts the web server, which then sends a file called a RealPlayer metafile back to your browser. This metafile is a small text file that has the true locationthe URLof the RealPlayer sound file you want to play. The metafile also has instructions telling your web browser to launch the RealPlayer sound player, which is required to play the clip.

What is a meta-search engine?

With this software, such as Copernic, you type a search on your own computer. The software then submits the search to many Internet search engines, indexes simultaneously, compiles the results for you, and then delivers the results to your computer. To visit any resulting site, just click the link, the same as if you were on an index or a search engine site.

XML-RPC

XML-RPC (Remote Procedure Call) is the most basic XML protocol to exchange data between a wide variety of devices on a network. It uses HTTP to quickly and easily transfer data and communication other information from client to server.

Server Push

a process by which a server maintains an open connection with a browser after the initial request for a page. through this open connection, the server continues to provide updated pages and content even though the visitor has made no further direct requests for such information Server push is more complicated than client pull, but it enables inline animation that does not require an entire web page to load each animation frame. The HTML source code for a server push animation is deceptively simple. The (image) tag references the animation just like a static picture or icon.

audio streaming

an audio file delivered to a computer-like device from a website so that it can be heard while it is coming into the device but cannot be saved or stored

How does iTunes work?

iTunes isn't file-sharing software like BitTorrent or like Kazaa was. Instead, it's software owned by Apple that lets you buy or listen to music on your PC or Mac, and transfer the music to your iPod.

The field of web development is generally broken down into:

- front-end (the user-facing side) - back-end (the server side).

What are two major components of CMS?

-A content management application (CMA), as the front-end user interface that allows a user, even with limited expertise, to add, modify, and remove content from a website without the intervention of a webmaster; -A content delivery application (CDA), that compiles the content and updates the website.

Differences between APIs and Web Services

-APIs can be hosted within an app or IIS (Internet Information Services), but a web service can only be hosted on IIS. - Web services are not an open source and are used to understand JSON (JavaScript Object Notation) or XML, whereas APIs are an open source and only used for XML. - API is a light-weight architecture (best for limited bandwidth devices (e.g. smartphone). Web services are not lightweight architectures since they require SOAP to send and receive network data. - APIs can use any form of communication, but a Web service only uses SOAP, REST, and XML-RPC. - APIs support URL, request/response headers, caching, versioning, content formats. Web services only support HTTP.

Similarities between APIs and Web Services

-Both are accessed through HTTP/HTTPS to enable communication between services providers and customers. - Both call a function, process data, and receive a response

What are the four parts of URL construction?

1) The first part of the URL indicates which type of transfer protocol will be used to retrieve the specified document. The most common request is for a hypertext document that uses the HTTP protocol. 2)The second portion of the URL refers to the specific host computer on which the document resides, which is to be contacted by the browser software. This part of the address is also called the domain name. 3)The third part of the URL is the directory on the host computer that contains a specific website or multiple websites. This is always located after the first single slash in the URL and is essentially the subdirectory on the hard disk that houses the website. 4)The last segment of a URL is the filename of a specific webpage you are requesting.

What are the different types of server softwares and what do they do?

1)database servers, 2)FTP servers, or network servers They perform various types of services for various types of clients. Specifically, a web server is an HTTP server, and its function is to send information to the client software (typically a browser) using the Hypertext Transfer Protocol (HTTP).

CGI (Common Gateway Interface)

A communications protocol by which a web server can communicate with other applications which creates Image Maps and Interactive forms.

What is CMS?

A content management system (CMS) is a computer software used to manage the creation and modification of digital content.

set-top box

A device that adds "Smart TV" features, such as Internet streaming and show recording, to normal TVs

How wireless WiFi networks work?

A key component of an 802.11 network (also called a WiFi network) is an access point or router also called an AP). The access point consists of a radio transmitter and receiver as well as an interface to a wired network such as an Ethernet network, or directly to the Internet. The access point serves as a base station and a bridge between the wireless network and a larger Ethernet network or the Internet.

What is a key feature of Web Services?

A key feature of web services is that applications can be written in various languages and are still able to communicate by exchanging data with one another via a web service between clients and servers. A client summons a web service by sending a request via XML, and the service then responses with an XML response. Web services are also often associated with SOA (Service-Oriented Architecture).

Hyperlink

A link from a hypertext file or document to another location or file, typically activated by clicking on a highlighted word or image on the screen

Pieces of hardware and its functions

A variety of hardware processes those packets and routes them to their proper destinations. This hardware is designed to transmit data between networks and makes up much of the glue that holds the Internet together. Five of the most important pieces of hardware are hubs, bridges, gateways, repeaters, and routers.

What does a web server do and how?

A web server does more than send pages to the browser, however. It passes requests to run Common Gateway Interface (CGI) scripts to CGI applications. These scripts run external mini-programs, such as a database lookup or interactive forms processing. The server sends the script to the application via CGI and communicates the results of the script back to the browser, if appropriate.

How does a web service work?Example

A web service sits between two sets of java, .net, or PHP apps providing a way for these applications to communicate over a network. On one side, for example, a java app interacts with the java, .net, and PHP apps on the other end by way of the web service communicating an independent language.

Web services and .NET similarities

Both require that applications be written and then run using XML, SOAP, WSDL, UDDI, and related technologies.

Bridges

Bridges link local area networks (LANs) with one another. They enable data destined for another LAN to be sent there, while keeping local data inside its own network.

What is Web Development?

Building and maintenance of websites It's the work that happens behind the scenes to make a website look great, work fast and perform well with a seamless user experience. Web developers, or 'devs', do this by using a variety of coding languages. The languages they use depends on the types of tasks they are performing and the platforms on which they are working.

What are cable modems used for?

Cable modems offer extremely high-speed access to the Internet. They enable you to access the Net using the existing coaxial TV cable that comes into your house. Cable modems offer T1-like and faster speeds, but at a fraction of the cost of T1 lines. They can deliver these high speeds because they are sent through highcapacity cable lines. Because Internet data and the normal cable signal coexist on the same lines, you can access the Net and watch TV simultaneously

What is the language of Web?

Hypertext Markup Language (HTML) is the markup language of the Web. It defines the format of a web document and enables hypertext links to be embedded in the document. You can use any text editor or word processor to add HTML tags to an ASCII text document, although a number of shareware and commercially available HTML editors can assist web page authors as well.

How does Hyperlink work?

Hypertext links are embedded into a web document using Hypertext Markup Language (HTML). The "hyperlinking" begins when you first retrieve a web page from a remote web server. Target links within the page move you quickly from one part of the page to the next.

Interactive forms

Interactive forms are HTML-based pages you fill out by providing information such as your name, email address, and similar information. In working with an interactive form, the user clicks a data-entry submit button. The data in the data fields is sent to the server with the request.

What is the Internet?

Internet is a collection of thousands of individual networks and organizations, each of which is run and paid for on its own. Each network cooperates with other networks to direct Internet traffic so that information can pass among them. Together, these networks and organizations make up the wired world of the Internet. For networks and computers to cooperate in this way, however, a general agreement must take place about things such as Internet procedures and standards for protocols. These procedures and standards are laid out in requests for comment (RFCs) that are agreed on by Internet users and organizations.

What are the major domains of the internet?

Major domains refer to the letters at the end of a plain English address, such as .com, edu, mil, org, ba. Domains are organized in a hierarchical manner, so that beneath major domains are many minor domains

Who provides API and what is it used for?

Most web services provide an API, which, with its set of commands and functions, is used to retrieve data.

SOAP vs. REST Web Services

RESTful web services and SOAP offer different variations. For example, a REST web service is generally a better choice when time is a factor, but SOAP wins out when building a service with multiple, non-CRUD methods. Then there are times when both options are the right answer. That's the case for two of the world's biggest e-commerce companies: Amazon and eBay use web services for both REST and SOAP.

Repeaters

Repeaters amplify the data at intervals so the signal doesn't weaken when it goes around the world.

Routers

Routers play a key role in managing Internet traffic. Their job is to ensure the packets always arrive at the proper destination. If data is being transferred among computers that are on the same LAN, routers often aren't necessary because the network itself can handle its internal traffic. Routers come into play when the data is sent between two different networks. Routers examine packets to determine their destinations. They take into account the volume of activity on the Internet, and they send the packet to another router that is closer to the packet's final destination.

SOAP Web Services

SOAP is defined as Simple Object Access Protocol. This web service protocol exchanges structured data using XML and generally HTTP and SMTP for transmission. SOAP also uses WSDL (Web Services Description Language) documents to distribute a web service description model. This describes how the SOAP requests (client-side) and responses (server-side) must appear. Additionally, SOAP web Services have standards for security and addressing. Pros: Usually easier to consume, more standards (WSDL, etc.), distributed computing Cons: Difficult set-up, more convoluted coding, harder to develop.

What is SOAP?

Simple Object Access Protocol (SOAP) is the web services communication standard.

What does TCP do and what does IP do?

TCP (Transmission Control Protocol) breaks down and reassembles the packets, whereas IP (Internet Protocol)is responsible for ensuring the packets are sent to the right destination.

Why do we use TCP/IP?

TCP/IP is used because the Internet is what is known as a packet-switched network. In a packet-switched network, there is no single, unbroken connection between sender and receiver. Instead, when information is sent, it is broken into small packets, sent over many different routes at the same time, and then reassembled at the receiving end.

How does the TV/Internet connection work?

TV/Internet connection work through cable modems, interactive TV (which uses the Internet to deliver information to people on their TV screens), and IPTV, which uses the Internet's underlying protocols to deliver TV signals to people's homes over telephone lines.

How the world wide web works?

The World Wide Web is the most innovative and most-used part of the Internet. When you browse the Web, you view multimedia pages composed of text, graphics, sound, and video. The Web uses hypertext links that allow you to jump from one place to another on the Web. The language that enables you to use hypertext links and to view web pages is called Hypertext Markup Language, more commonly known as HTML.

RESTful Web Services

The acronym REST, or sometimes ReST, stands for Representational State Transfer and is an architectural style, meaning each unique URL represents an individual object of some sort. A REST web service uses HTTP and supports/repurposes several HTTP methods: GET, POST, PUT or DELETE. It also offers simple CRUD-oriented services. HTTP codes. Pros: Lightweight, human readable, easier to build Cons: Point-to-point communication, lack of standard

What is back end development?

The backend developer engineers what is going on behind the scenes. This is where the data is stored, and without this data, there would be no frontend. The backend of the web consists of the server that hosts the website, an application for running it and a database to contain the data.

What is a client?

The client is a local personal computer or the software that runs on it

What are the true web services?

The only true web services are those that use a number of specific protocols and technologies.

What happens when packets are sent to a router's input port faster than the port can process them?

The packets are sent to a special holding area called an input queue, which is an area of RAM on the router.

How does the Web work with databases?

The search begins on a web page that includes a form field to accept search terms and HTML codes to execute a CGI script. The browser might pass the data to the web server in a query string. The query stringcontains the name of the CGI script in a directory called cgi-bin. This directory is followed by search parameters that include the search terms, separated by ampersands (the character "&"). A question mark is used to separate the name of the script or document from the arguments that are to be passed to it. Certain characters must be encoded when passed in a URL. Spaces, for example, are replaced by plus signs "+".

What are Markup languages?

They are sets of directions that tell the browser software how to display and manage a web document. en music scores are instructions that tell a musician how to play a particular song. These instructions (called tags or markups) are embedded in the source document that creates the web page. Markup languages are much simpler and describe the way information should be displayed. In markup languages, tags are embedded within documents to describe how the documents should be formatted and displayed.

Cons of Wifi

They can be vulnerable to snoopers and hackers, who can use a technique called war driving to get into the network.

What are web browsers?

Web browsers are pieces of software that interpret the language of the Web, Hypertext Markup Language (HTML), and then display those results on your computer. The chapter begins by delving into how browsers do that job.

What are web pages?

Web pages are, in essence, multimedia publications that can include music, audio, video, and animation, as well as graphics and text. Web pages are connected via hypertext that enables you to jump from any page to any other page, and to graphics, binary files, multimedia files, and other Internet resources. To jump from one page to another, or to another resource, you merely click a hypertext link.

What is a Web Service?

Web services include any software, application, or cloud technology that provides standardized web protocols (HTTP or HTTPS) to interoperate, communicate, and exchange data messaging - usually XML (Extensible Markup Language) - throughout the internet.

What are Web and .NET services?

Web services, and its cousin, .NET, are little known technologies that use the Internet to dramatically increase businesses' and individuals' productivity. They allow programs and services to be run remotely across the Internet, and also allow services to be delivered automatically to people's desktops. they're simply modular software components wrapped inside a specific set of Internet communications protocols, which can be run across the Internet. They're quietly revolutionary technologies because they in essence can do away with the need for an operating system to run the software.

How Computer Networks Send Data Across the Internet

When you send information across the Internet, the Transmission Control Protocol (TCP). Your computer sends those packets to your local network, the Internet service provider (ISP), or online service. From there, the packets travel through many levels of networks, computers, and communications lines before they reach their final destinations, which might be across town or around the world.

How does a wireless wifi network work?

Wi fi card needs to be used in a computing device such as a laptop or palmtop computer, and it needs to connect to a nearby compatible wireless access point, most often called a router. These routers can be in a home or business. Increasingly there are also public access points, called hot spots, which allow you to connect to the Internet from public places

routing table

generated automatically by software, is used to determine the best possible route for a packet

DSL connection

is a technology that provides high-speed Internet connection using regular copper telephone lines. DSL modems connect to your computer via a much higher-speed port, either an Ethernet port or a USB port, and they maintain an always-on connection over your phone line. So, you always have an Internet connection when they are plugged into your PC and turned on.

How do we divide router physicial ports?

receiving (input) ports (When an input port receives a packet, a software routine called a routing process is run. This process looks inside the header information in the IP packet and finds the address to which the data is being sent. It then compares this address against an internal database called a routing table. The routing table has detailed information about the ports to which packets with various IP addresses should be sent.) sending (output) ports (output port then sends the data to the next router or to the destination itself.)