WEB TEWCHNOLOGY-ANS

walkingceilInternet και Εφαρμογές Web

22 Οκτ 2013 (πριν από 3 χρόνια και 10 μήνες)

98 εμφανίσεις

5 MARKS

1. WEB TECHNOLOGIES

web technologies that rela
te to the interface between web
servers and their clients. This information
includes markup languages, programming interfaces and languages, and standards for document
identification and display.

1.

Markup

Languages Section
-

Includes all markup languages including HTML, XML, and SGML.
Documentation in this section currently includes an HTML Guide, XML Guide, and a Document
Type Definition (DTD) reading reference.

2.

CGI Section
-

Includes four documents descri
bing implementation of the client to server web
interface. It includes information about the common gateway interface (CGI), server side
includes (SSI), JavaScript, and writing perl script programs

3.

HTTP Section
-

Thic section currently includes an HTTP Ref
erence which is based on RFC 2616.
It has brief descriptions of the HTTP request and response headers and also lists the possible
response headers such as 404 (not found).

4.

PHP
-

PHP is a scripting language that runs on the web server and the script code is

embedded
in the HTML document. It is easy to use with syntax similar to C which is why it is so popular.
This section includes a PHP Introduction manual.

5.

JAVA Section
-

Documentation is being generated for this section. It currently contains some
web link
s.

6.

MIME Section
-

This section describes Multipurpose Internet Mail Extension along with its
purpose and it also includes a few MIME related web links.

7.

Graphics
-

Gif files used to add graphics to web pages.

2.CHARACTERISTICS OF WEB TECHNOLOGY

A list of wa
ys that people can volunteer to improve Mass Effect Wiki, on the main page of that site.
Mass Effect Wiki is an example of content generated by

users working collaboratively.
Edit box
interface through which anyone could edit a
Wikipedia

article.
Web 2.0 websites allow users to do more
than just retrieve information. By increasing what was already possible in "
Web 1.0
", they
provide the user with
more user
-
interface, software and storage facilities, all through their browser. This has been called
"Network as
platform"

computing.
[3]

Major features of Web 2.0 include social networking sites, user contributed sites, self
-
publishing platforms, tagging, and social bookmarking.
[15]

Users can provide the data that is on a Web 2.0 site
and exercise some control over that data.
[3]
[16]

These sites may have an "Architecture of participation" that
encourages users to add value to the application as they use it.
[2]
[3]

Some scholars have made the case that
cloud computing

is a form of Web 2.0 because cloud computing i
s simply an implication of computing on the
Internet.
[17]
The concept of Web
-
as
-
participation
-
platform captures many of these characteristics. Bart Decrem,
a founder and former CEO of
Flock
, calls Web 2.0 the "participatory Web"
[18]

and regards the Web
-
as
-
information
-
source as Web 1.0.The Web 2.0 offers all users the same freedom to contribute. While this opens
the possibility for serious debate and collaboration, it also opens the
possibility for
"spamming"

and
"trolling"

by less mature users. The impossibility of e
xcluding group members who don’t contribute to the provision of
goods from sharing profits gives rise to the possibility that serious members will prefer to withhold their
contribution of effort and
free ride

on the contribution of others.
[19]

This requires what is sometimes called
radical trust

by the management of the website. According to Best,
[20]

the characteristics of Web 2.0 are: rich
user experience, user participation, dynamic content,
metadata
, web standards and
scalability
. Further
characteristics, such as openness, freedom
[21]

and
collective intelligence
[22]

by way of use
r participation, can
also be viewed as essential attributes of Web 2.0.The
client
-
side
/web browser technologies used in Web 2.0
development are
Asynchronous JavaScript

and XML (
Ajax
),
Adobe Flash

and the
Adobe Flex

framework, and
JavaScript
/Ajax frameworks such as
YUI Library
,
Dojo Toolkit
,
MooTools
,
jQuery

and
Prototype JavaScript
Framework
. Ajax programming uses JavaScript to upload and download new data from the web server with
out
undergoing a full page reload.

3.BUSINESS APPLICATIONS

Web applications have a variety of business uses. The most common is e
-
commerce, but you may
have need of other types of solutions that extend your business into the Internet or over a corporate
in
tranet or extranet. For all of these types of business applications, the basic principles of Web
development apply.Because e
-
commerce is the most common type of Web application for the
Internet, this section discusses e
-
commerce applications in general and

e
-
commerce resources
specifically for FrontPage.E
-
commerce applications allow you to sell goods and services to anyone
anywhere in the world. However, e
-
commerce is more than just posting a Web site of products. E
-
commerce solutions generally involve data
bases and credit card processing. Security is important for
e
-
commerce applications, so you should carefully and thoroughly research security measures that you
or your hosting company take on the Web server.The following links provide general information
a
bout e
-
commerce. You can perform your own search to locate e
-
commerce vendors and hosting
companies.

General E
-
commerce Resources



Ecommerce Guide on Internet.com




E
-
Commerce Times




CommerceNet




Electronic Markets


Microsoft and FrontPage E
-
commerce Resources



E
-
Commerce and FrontPage 2002




Microsoft Small Business Solutions for Retail Businesses




Secure Sockets Layer: Protect Your E
-
Commerce Web Site with SSL and Digital Certificates




Add E
-
Commerce to Your App with XML and SQL Server 2000


Ecma International

Ecma International is
involved with developing global standards for information and communications
systems technologies and for global communication networks, of which the Internet is part. (Prior to
1994, Ecma was known as the European Computer Manufacturers Association, or EC
MA.) Ecma also
provides standards for Internet scripting and programming languages. ECMAScript standards form the
basis of the JavaScript, JScript, and C# programming languages.

IETF

IETF stands for Internet Engineering Task Force. The HTML Working Group o
f the IETF originally
defined the HTML language specification. In 1996, the World Wide Web Consortium took over this
task. However, the IETF continues to be an independent standards body with a large community of
members dedicated to evolving Internet arch
itecture and defining Internet protocols.


20 MARKS

1.
INTRODUCTION OF

WEB TECHNOLOGIES

There are many Web technologies, from simple to complex, and explaining each in detail is beyond
the scope of this article. However, to help you get started with develop
ing your own Web sites,
beyond simple WYSIWYG designing of Web pages in FrontPage, this article provides brief definitions
of the major Web technologies along with links to sites where you can find more information,
tutorials, and reference documentation.

Important

The links included in this article are only a representative set of resources that are
available on the Internet. Where appropriate, this article cites Microsoft resources, but you can also
find many links to non
-
Microsoft resources. You can lo
cate additional resources by performing your
own Web searches.

Markup Languages

Markup is used to in text and word processing documents to describe how a document should look
when displayed or printed. The Internet uses markup to define how Web pages shoul
d look when
displayed in a browser or to define the data contained within a Web document.

There are many different types of markup languages. For example, Rich Text Formatting (RTF) is a
markup language that word processors use. This section describes the
most common markup
languages that are used on the Internet.

HTML

HTML stands for Hypertext Markup Language. HTML is the primary markup language that is used for
Web pages. HTML tells the browser what to display on a page. For example, it specifies text, im
ages,
and other objects and can also specify the appearance of text, such as bold or italic text.

The
World Wide Web Consortium

(W3C) defines the specification for HTML. The current versions of
H
TML are
HTML 4.01

and
XHTML 1.1
.

Note

DHTML stands for Dynamic HTML. DHTML combines cascading style sheets (CSS) and scripting
to cr
eate animated Web pages and page elements that respond to user interaction.

XML

XML stands for Extensible Markup Language. Similar to HTML, XML is a markup language designed for
the Internet. However, unlike HTML, which was designed to define formatting of

Web pages, XML was
designed to describe data. You can use XML to develop custom markup languages.

Programming Languages and Technologies

Programming languages enable you to create custom applications and add functionality that is not
already part of an ap
plication. On the Internet, programming languages enable you to create visual
animation, respond to user actions, validate forms, interact with databases, and provide e
-
commerce
solutions.Programming languages come in two flavors: interpreted and compiled.

Most scripting
languages are interpreted, which means that you write the code and the browser or server
understands what to do with it. Compiled languages require an added step that translates the code
into machine language code, which is then stored in a

separate file with either a .dll or .exe file name
extension.

JavaScript (JScript/ECMAScript)

JavaScript is an interpreted scripting language commonly used on the Internet for creating Web pages
that respond to user actions, such as when a user moves a mo
use pointer over an image or clicks a
form button. Combined with HTML and CSS, JavaScript allows you to create Dynamic HTML pages.

JavaScript is generally used for client
-
side scripting; as a result, users can easily view JavaScript code
along with the HTM
L code in a page. Although it may be used for server
-
side scripting, JavaScript
works best for visual animation (such as changing an image when a user moves the mouse pointer
over it) or for validating form fields.

VBScript

VBScript is an interpreted scrip
ting language that is a subset of Microsoft Visual Basic. As a result, the
structure and syntax are similar to Visual Basic, making VBScript an easy scripting language to learn.

Although VBScript can be used for client
-
side scripting in Internet Explorer,
most other browsers do
not include a VBScript interpreter. Therefore, VBScript is most commonly used in server
-
side scripting
for Web pages that use classic
ASP
.

Visual Basic .NET

Visual Basic .NET is the next generation of the Visual Basic programming language. Visual Basic .NET is
a compiled, object
-
oriented language that leverages the .NET Framework for developing powerful
ASP.NET We
b applications.

Visual Basic .NET uses the same syntax as earlier versions of Visual Basic but also leverages the
namespaces and classes that are part of the .NET Framework. As with VBScript and earlier versions of
Visual Basic, Visual Basic .NET is a rel
atively easy programming language to learn.

Java

Java is a compiled object
-
oriented programming language that was designed for use on the Internet.
In 1995, Sun Microsystems designed the Java programming language and introduced it to Web
developers as a wa
y to include animation and dynamic elements in Web pages. Java syntax is similar
to C++ but is considered easier to learn.Java code is generally used for server
-
side processing but can
also be run on the client by using the
Java virtual machine
.

ASP

ASP is an abbreviation for Active Server Pages. ASP is a server
-
side scripting technology that you can
use to create dynamic Web pages. ASP code is generally embedded in the HTML within a page, and
HTM
L pages that contain ASP have an .asp file name extension; however, because

processing is done
on the server, the ASP code is not sent to the browser, and visitors to your site never see your ASP
code. Client computers receive only the resulting HTML.

ASP.
NET

ASP.NET is the next generation of server
-
side processing for
ASP

programming. You can write ASP.NET
code in C#, Visual Basic .NET
, or any language that is supported by the .NET Framework. Because
ASP.NET is part of the .NET Framework, you can develop ASP.NET applications that utilize any of the
namespaces and classes in the .NET Framework.

2.WEB SERVERS AND SERVER PRODUCTS

A Web ser
ver is the computer on which you host your Web site. It is connected directly to the Internet
and sends hosted Web pages to the client using the Hypertext Transfer Protocol (HTTP). If you host
your FrontPage site through an Internet service provider (ISP),

Web presence provider (WPP), or Web
host provider (WHP), you may have access to several different types of Web servers. The most
common Web servers available are Windows
-
based servers running Microsoft Internet Information
Services (IIS) and UNIX
-
based se
rvers running Apache.Depending on how you develop your Web site,
you may have specific server requirements. For example, ASP requires a Windows
-
based Web server;
PHP requires a PHP interpreter. You should discuss your needs with your provider or verify tha
t your
Web server provides the required resources
\

for server
-
side processing.

Internet Information Services

Internet Information Services (IIS) is a Web server designed to process HTTP and FTP requests on
Windows operating systems. IIS is part of the Micr
osoft Windows NT, Microsoft Windows 2000, and
Microsoft Windows 2003 operating systems, and you can install and enable IIS on Windows XP
-
based
computers for testing ASP and ASP.NET applications.

Apache

Apache is an open
-
source Web server that runs on UNIX
operating systems, such as Solaris and Linux,
but can also be installed on Windows
-
based servers. Apache Web servers provide simple HTTP
processing.

FrontPage Server Extensions

The FrontPage Server Extensions from Microsoft are a set of programs that suppo
rt administering,
authoring, and browsing a FrontPage
-
extended Web site. Users running the FrontPage client can
create and manage professional
-
looking Web sites, whether they are creating personal Web pages or
corporate Internet or intranet sites. FrontPag
e Server Extensions give you, as the administrator, tools
for managing site security, organizing your content into sub sites, and checking site usage.

SharePoint Team Services

SharePoint Team Services from Microsoft is a server technology designed for work
group collaboration
and includes features for sharing files and information over a corporate network. SharePoint Team
Services incorporates the FrontPage 2002 Server Extensions. As a result, much of the documentation
about SharePoint Team Services also con
tains information about administering FrontPage Server
Extensions.

Windows SharePoint Services

Microsoft Windows SharePoint Services is the second generation of SharePoint Team Services. The
same as SharePoint Team Services, Windows SharePoint Services is
a server technology designed for
workgroup collaboration over an intranet or extranet. Windows SharePoint Services includes many of
the features that were part of SharePoint Team Services.

Databases

Databases allow you to store information for easy retriev
al. On the Internet, databases are used to

store users' logon information, product information, and customers' orders, among other things.
There are almost as many database products as there are reasons and ways to use databases.When
you create a database

from within FrontPage, FrontPage automatically creates a Microsoft Access
database.

Access

Microsoft Access is an easy database application with which to work and provides powerful database
capabilities. Because Access databases are file
-
based rather than

server
-
based, all you need to work
with Access databases is the database file itself, which has a file name extension of .mdb. You can
easily transfer this file to the hosting Web server, and access the data inside the file by using ASP,
PHP, or the Datab
ase Interface Wizard in FrontPage.

SQL Server

Microsoft SQL Server is a secure, robust, and scalable database application that can grow with the
needs of e
-
commerce and financial Web applications. If you choose to use the SQL Server database
platform, you
need SQL Server installed on the host Web server. If you do not control your host Web
server, you need to verify that your ISP provides SQL Server database services.

Oracle Database

Oracle Database is a powerful relational database management system develo
ped by . Oracle, like SQL
Server, is a database application for large, transaction
-
based and e
-
commerce Web applications.

3.SEMANTIC WEB TECHNOLOGY

The
Semantic Web

is a collaborative movement led by the
World Wide Web Consortium

(W3C)
[1]

that
promotes common
fo
rmats for data
[
disambiguation needed
]

on the
World Wide Web
. By encouraging the
inclusion of
semantic

content in web pages, the Semantic Web aims at converting the current web of
unstructured document
s
[
clarification needed
]

into a "web of data". It builds on the W3C's
Resource
Description Framework

(RDF).
[2]

Limitations of HTML

Many files on a typical computer can be loosely divided into human readable
documents

and machine
readable
data
. Documents like mail messages, reports, and brochures are read by humans. Currently,
the World Wide Web

is based mainly on documents written in
Hypertext Markup Language

(
HTML
), a
markup convention

that is used for coding a body of text interspersed with multimedia objects such as
images and interactive forms. Metadata tags provide a method by which computers can categorise
the content of web pages
.

Semantic Web solutions

The Semantic Web takes the
solution further. It involves publishing in languages specifically designed
for data:
Resource Description Framework

(RDF),
Web Ontology Language

(OWL), and Extensible
Markup Language (
XML
). HTML describes documents and the links between them. RDF,

OWL, and
XML, by contrast, can describe arbitrary things such as people, meetings, or airplane parts.

4.
WEB
-
BASED APPLICATIONS AND DESKTOPS

Ajax

has prompted the devel
opment of websites that mimic desktop applications, such as
word
processing
, the
spreadsheet
, and
slide
-
show presentation
. In 2006
Google, Inc.

acquired one of the
best
-
known sites of this broad class,
Writely
.
[56]

W
YSIWYG

wiki

and
blogging

sites replicate many
features of PC authoring applications.

Several browser
-
based "
operating systems
" have emerged, including
EyeOS
[57]

and
YouOS
.(No longer
active.)
[58]

Although coined as such, many of these services function less like a traditional operating
system and
more as an application platform. They mimic the user experience of desktop operating
-
systems, offering features and applications similar to a PC environment, and are able to run within any
modern browser. However, these so
-
called "operating systems" do not

directly control the hardware
on the client's computer.

Numerous web
-
based application services appeared during the
dot
-
com bubble

of 1997

2001 and
then vanished, having faile
d to gain a critical mass of customers. In 2005,
WebEx

acquired one of the
better
-
known of these,
Intranets.com
, for

$45 million.
[59]

Distribution of media


XML and RSS

Many regard syndication of site content as a Web 2.0 feature. Syndication uses standardized protocols
to permit end
-
users to make us
e of a site's data in another context (such as another website, a
browser plugin, or a separate desktop application). Protocols permitting syndication include
RSS

(really

simple syndication, also known as web syndication),
RDF

(as in RSS 1.1), and
Atom
, all of them
XML
-
based formats. Observers have started to refer to these technologies as
web feeds
.

Specializ
ed protocols such as
FOAF

and
XFN

(both for social networking) extend the functi
onality of
sites or permit end
-
users to interact without centralized websites.

Web APIs

Web 2.0 often uses machine
-
based interactions such as
R
EST

and
SOAP
. Servers often expose
proprietary
Application programming interfa
ces

(API), but standard APIs (for example, for posting to a
blog or notifying a blog update) have also come into use. Most communications through APIs involve
XML or
JSON

payloads.

REST APIs, thr
ough their use of self
-
descriptive messages and
hypermedia as the engine of application
state
, should be self
-
describing once an entry
URI

is known.
Web Services Description Language

(WSDL) is the standard way of publishin
g a SOAP API and there are
a range of web service
specifications
.
EMML
, or E
nterprise Mashup Markup Language by the
Open Mashup Alliance
, is an
XML markup language for creating enterprise mashups.

Business Semantics Management

[1]

[2]

(BSM) encompasses the technology, methodology,
organi
zation, and culture that brings business stakeholders together to collaboratively realize the
reconciliation of their heterogeneous metadata; and consequently the application of the derived
business semantics patterns to establish semantic alignment betwee
n the underlying data structures.

Semantic Reconciliation

Semantic reconciliation is a process cycle constituted of four subsequent activities: scope, create,
refine, and articulate. First, the community is scoped: user roles and affordances are appointed
. Next,
relevant facts are collected from documentation such as, e.g., natural language descriptions, (legacy)
logical schemas, or other metadata and consequently decomposing this scope in elicitation contexts.
The deliverable of scoping is an initial uppe
r common ontology that organizes the key upper common
patterns that are shared and accepted by the community. These upper common patterns define the
current semantic interoperability requirements of the community. Once the community is scoped, all
stakehold
ers syntactically refine and semantically articulate these upper common patterns.


Pragmatic Perspective Unification

During unification, a new proposal for the next version of the upper common ontology is produced,
aligning relevant parts from the common and

divergent stakeholder perspectives. Ultimately, if the
semantic reconciliation results in a number of reusable language
-
neutral and context
-
independent
patterns for constructing business semantics that are articulated with informal meaning descriptions,
t
hen the unification is worthwhile

Semantic Application

Semantic application is a process cycle constituted of two subsequent activities: select and commit
where the scoped information systems are committed to selected consolidated business semantic
pattern
s. This is done by first selecting relevant patterns from the pattern base. Next, the
interpretation of this selection is semantically constrained. Finally, the various scoped sources and
services are mapped on (read: committed to) this selection. The sele
ction and axiomatization of this
selection should approximate the intended business semantics. This can be verified by automatically
verbalization into natural language, and validation of the unlocked data. Validation or deprecation of
the commitments may
result in another iteration of the semantic reconciliation cycle.