Internet
If the twentieth century is said rightly that belonged
engineering the recent years culminating in the development of informatics and
cybernetics through finished goods computers coming century is said to be of
communication. If at first were morse signals, then the telegraph
revolutionized communications phone that things have evolved strong at the end
of this century culminad today with a new and powerful concept called the
Internet. What is the Internet, a brief history and how it works I will explain
in the following lines.
Internet history and how it works
Also called network of networks, the Internet originated in
the ARPANET and NSFNET in. The Internet is more than a sum of the related
course nobody foresaw how this transition from a military.
How does it work? How do I connect to the Internet?
In the 60 US Department of Defense needed a communication
network in case of a nuclear attack. Military RAND Corporation proposed a
centralizing communications in a network. This continuous network nodes capable
of transmitting and receiving messages. Each node had its own address so that
the message can convey a particular node. Department of Defense Advanced
Project (The Defense Department's Advanced Research Projects Agency) known as
ARPA and DARPA decided to expand this network. In 1969 the first border
Message Processor, the precursor of today's router was installed at UCLA (University of California
in Los Angeles )
that ARPANET began to expand. ARPANET include some services that are important
today in the Internet today, such as FTP (File Transfer Protocol), remote login Telnet and E-mail (electronic mail). While the ARPANET starts to grow, develop
technology companies like Xerox local networks (LAN). Network with the most
impact was Ethernet, which allowed network connecting multiple computers
together. The first version had a theoretical transfer rate of 3 Mbps and 10
Mbps later. Researchers from the ARPANET began to believe it would be useful to
connect LANs to ARPANET. To achieve this we have developed a protocol for
connecting different types of equipment. Thus TCP (Transmission Control
Protocol) and Internet Protocol (IP). In 1983 growth was spurred by the
emergence of the Internet version of 4.2 BSD UNIX contained and TCP , IP.
How does the Internet
To understand how the Internet works, you must understand
that the Internet is not a homogeneous entity. Indeed it is a great miracle
that still works. The Internet has a structure, so if you want to send an E-mail
message neighbor's computer have to travel hundreds of miles. Moreover, the
cars were not built are connected to communicate directly with each other. Yet
the Internet works.About the most popular network protocols
Structure of the Internet
Bridge is started for all Internet ISP (Internet Service
Provider). An ISP may be commercial or a school or a college, university, etc. Some
users may be connected in LAN, others can access the Internet using a modem and
PPP or SLIP connection. All ISPs are connected to the Internet by other ISPs. At
the lowest level, a local ISP is connected to another local ISP. The next level
is the ISPs that connect to other ISPs from outside.
Routers and TCP / IP
How your application finds its way to a website and how
information finds its way, is determined by two things: routers and TCP / IP. Routers are similar to telephone operators. They connect
networks together and have routing tables to determine how the information flow
to and from the Internet. The routers have an IP for each connection, such as a
router that has a PPP connection and two Ethernet connections should have three
IPs. The secret that makes the Internet go is TCP , IP. IP is the component
that move data packets to a network node to another. TCP is the component that
checks if the data in the right place. IP is a unique number for each computer.
There are three classes of IP addresses. Class A uses the first number to
identify the network and the last 3 numbers to identify your computer. Class B
uses the first two numbers identify the network and the last two numbers to
identify your computer. Class C first 3 numbers used to
identify the network and only the last number to identify your computer. Class
IP is closely related to the number of computers on the network. But that is
easier to remember a name than a number and a Domain Name Internet use. If the
router is the operator of the Internet, the Domain Name Service (DNS) is the
telephone. So you can send me an email using the name and IP popesculauragrupa54@192.34.55.34
or simply popesculauragrupa54@yahoo.com
SLIP and PPP
The most common ways to connect to the Internet using a
modem Serial Line Interface Protocol are (SLIP) and Point Protocol to PRIVACY (PPP).
If your ISP allows using SLIP and PPP PPP choose because it is faster and I'm
sure. SLIP is not correct but is easier to configure than the PPP connection. To
use one of these methods to access, ISP, you must provide this service. You
also need to have software that supports SPLIP , PPP.
How can I connect
Modems, direct, and Internet connection To connect to the Internet need two things: an ISP and a way
to connect to this provider. The most common method to connect is using a modem
connected to the telephone line or to have direct access to the Internet.
Connecting in the Internet use a modem
The most common method to connect to the Internet using a
modem is connected to a phone line. The modem modulator / DEModulator is
required to convert digital signals into analog signals from the computer to be
transmitted on a regular phone line, and vice versa. Modems are available in
external version and internal version. External modems have their own housing, separate
power supply and connect with computer via serial cable. Internal modems
connected to a slot in the computer and use the source computer. Choosing the
modem you more taste than performance. Internal modems are cheaper than
external ones. External modems that provide various information display and can
be moved easily to another computer.
WWW
World Wide Web known as the WWW, W3, or simply Web made
Internet access to information for the average person to be much easier. WWW
Internet service that is developed most in recent years .
On the Web you can find information about a recipe or how to get an
thermonuclear bomb virtually all human knowledge is gathered there.
The term Internet, or internet and has several closely associated
meaning, depending on context :
Internet own name refers to the unique
global network of interconnected computers protocols Communication
Transmission Control Protocol and Internet Protocol, briefly called TCP , IP. The
precursor of the Internet dates back to 1965 when the Defense Advanced Research
Projects Agency created the first
network of interconnected computers called Arpanet. Super-network today
resulted from Arpanet network expansion.
Common noun internet written in lower case mean in most
cases the same network, but seen as a mass communication medium with the
information and services that are offered to users through this medium.
Technically, the term may designate a network that
interconnects two or more autonomous networks are far away from each other. Examples
of large networks which use this name is justified, are SIPRNet and FidoNet.The word Internet part comes from artificial
copulation of two English words: Interconnected and network interconnected
network.
Physical access to the Internet
There is a whole range of physical coupling method of a
computer or smart device Internet:
Through a modem and a phone line and fixed telephone
connection, by dialing a phone number,
Phone line dedicated / leased to a single user or a single
firm,
Connected wirelessly to a so-called hotspot or Active
Point, using techniques WLAN or Wi-Fi,
Radio connection from a mobile phone or a portable
computer terrestrial cellular antenna using GSM or
UMTS techniques.
Use
About 83% of the world population uses the Internet, according
to a press release from the European Computer Driving Licence Foundation.According to a study by research firm online
Internet World Stats in November 2007, the Internet penetration rate in Romania reached
31.4% of the total population, estimated at 22.27 million inhabitants, and the
number of broadband connections was 1,800,150.
No comments:
Post a Comment