INTRO TO WEB Flashcards
is a device for transmitting and receiving messages over long distances.
Telegraph
To be able to send message as quickly as possible
internet
the three 1st technology
telephone, telegraph, radio
calls were routed through operators who physically connected caller and receiver by connecting a wire to a switchboard to complete a circuit.
telephone networks
One of the weaknesses of having a physical connection is that you must establish a – and maintain a dedicated circuit for the duration of the call. This type of network connection is sometimes referred to as –
link , circuit switching
internet can be difficult to have multiple conversations –
simultaneously
internet requires more –, since even the silences are –
bandwidth, transmitted
ARPANET was created in
1960s
ARPANET did not use circuit switching but instead used an alternative communications method called –
packet switching
X.25 is created in
1974
USENET is created in
1978
To promote the growth and unification of the disparate networks, a suite of –was invented to unify the
networks.
protocols
is the name given to a formal set of publicly available rules that manage data exchange between two points.
protocol
allow any two computers to talk to one another, so long as they implement the protocol.
Communications protocols
on 1981, New networks built in the United States began to adopt the –
TCP/IP
protocols for the Internet were published and ready for use.
1981
on – TCP/IP was adopted across all of ARPANET.
January 1, 1983
TCP/IP networking was adopted across the globe.
2003
in – and –, email and text-based systems were dominant
Late 1980s and early 1990s
web inventor and founding director of the WWW foundation
Tim Berners-Lee & Robert Cailliau
Essential Elements of Early Web
Uniform Resource Locator (URL)
Hypertext Transfer Protocol (HTTP)
software program/ web server
Hypertext Markup Language (HTML)
Browser
can make HTTP requests to URLs and that can display the HTML it receives.
browser
to uniquely identify a resource on the WWW.
niform Resource Locator (URL)
to describe how requests and responses operate.
Hypertext Transfer Protocol (HTTP)
can respond to HTTP requests.
software program/ web server
to publish documents.
Hypertext Markup Language (HTML)
mosaic is released in – by – and –
1993 by Eric Bina and Marc Andreessen
is released in late 1994 cofounded by Marc Andreessen
Netscape Navigator
is released in 1995 by Microsoft Edge and became the market leader.
Internet Explorer
In late 1994, Berners-Lee helped found the –
World Wide Web Consortium (W3C)
is the international standards organization that oversee the growth of the web.
W3C
refers to an internal network using Internet protocols that is local to an organization or business
Intranet
intranet resources are often –
private
intranet uses the – such as TCP/IP
internet protocols
intranet accessible via the –
web browser
Consists only of HTML pages that always look identical for all users
Static Website
Static Website users could read the pages but could not provide –.
feedback
Dynamic server-side website
read content from –
and – with existing enterprise computer systems
databases, Interface
Dynamic server-side website communicate with – institutions
and – HTML that is sent to user’s browsers
financial , output
THREE WEB MODELS
Client-Server Model
The Request – Response Loop
The Peer-to-Peer Model
is a computer agent that active 24/7, listening for requests from clients.
SERVER
a computer agent that makes requests and receives responses from the server, in the form of response codes, images, text files, and other data
CLIENT
Is the most basic mechanism on the server for receiving requests and transmitting data in response.
The Request – Response Loop
In The Request – Response Loop, The client initiates a request to a server and gets a – that could include some resource like an –, an image, or some other data
response , HTML file
Each computer is functionally identical
and each node can send and receive data directly with one another.
The Peer-to-Peer Model
in The Peer-to-Peer Model, each peer acts as both a – and – and video chat and bit torrent protocols and examples
client and server
Server Types
web server
application server
database server
mail server
media server/ streaming server
authentication server
is a computer servicing HTTP requests.
web server
is a computer that hosts and executes web applications.
application server
is a computer that is devoted to running a Database Management System (DBMS), such as MySQL
database server
is a computer creating and satisfying mail requests, typically using the Simple Mail Transfer Protocol (SMTP).
mail server
is a special type of server dedicated to servicing requests for images and videos.
media server
handles the most common security needs of web applications
authentication server
distribute incoming requests between clusters of machines so that any given web or data server is not excessively overloaded.
Server Farm
distribute incoming requests to available machines
load balancers
Server farms are typically housed in special facilities called –
data centers.
A typical server farm will consist of many –, each containing many servers
server racks
contains computers and hard drives; sophisticated air conditioning systems; redundancy power systems using batteries and generators; specialized fire suppression systems; and security personnel are all part of a typical data center
data center
Working in Web Development
Tester/Quality Assurance
Business Analyst
Nontechnical Roles
Software Engineer
System Administrator
Types of Web Development Companies
Hosting Companies
Design Companies
Website Solution Companies
Start-Up Companies
Internal Web Development
Vertically integrated companies
is defined as a type of network that relies on a physical connection between two distinct network nodes, which requires the link to be set up before the nodes can communicate.
circuit-switched network
Before sending data across, the network ensures a patent, free and available path between the nodes in the network, joining the sender and receiving device.
Establishment of the circuit
data of any type, voice, data, analog or digital, is then sent across
Transfer of data:
After the data transfer, the circuit ends so that the bandwidth becomes available for other use.
Disconnection
Circuit switching is commonly used in – communication and some types of data communication.
voice
is a set of rules for formatting and processing data
protocol
is a measurement of how much data can (maximally) be transmitted along a communication channel
Bandwidth
In networking, a protocol is a set of rules for – and processing data.
formatting
