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Internet is a packet-switched network, in which information is broken into small packets and sent over
                 different routes at the same time, and then reassembled at the receiving end. TCP is the component
                 that collects and reassembles the packets of data, while IP ensures that the packets are sent to the right
                 destination.

                      Do you know?

                      TCP/IP was developed in the 1970s and adopted as the protocol standard for ARPANET (the predecessor
                      to the Internet) in 1983.

                 FTP


                 FTP stands for ‘File Transfer Protocol’. It is a set of rules for transferring files between two computers on
                 Internet. It is a commonly used protocol for exchanging files over any TCP/IP based network. The central
                 computer i.e., FTP server helps the users to upload and download files.
                 Using FTP, the client requests to initiate a file transfer, then the client and the server exchange files. FTP
                 allows communication between clients and servers but not between clients i.e., two people with FTP client
                 software cannot exchange files directly until the FTP server is in the middle.

                 The  most  common  application  of  FTP  is  to  download  files  from  the  Internet.  An  FTP  address  looks
                 like  an  address  of  a  website,  except  that  it  uses  the  prefix  ‘ftp://’  instead  of  ‘http://’.  An  example  of
                 FTP site address  is  ‘ftp://planet.com/’. There are two types of FTP connections: ‘Anonymous’ and
                 ‘Non-Anonymous’.

                 When connected to any FTP directory, the host system asks for the user’s name and password before allowing
                 access to the directory. With an anonymous FTP directory, the user’s name is always “Anonymous” and
                 the password is always the user’s e-mail address. While connecting to an FTP site that allows anonymous
                 logins, the user is not (frequently) prompted for a name and password. Hence, while downloading files
                 the users are most likely using an anonymous FTP login.

                 Non-anonymous FTP on the other hand, requires a unique username and password for the FTP directory
                 in question, which is provided by the FTP site administrator only. So the users are verified before they can
                 access or transfer files from their computer.

                 To make an FTP Connection

                 To make an FTP connection the user uses a standard web browser (Internet Explorer, Netscape, etc.) or a
                 dedicated FTP software program referred as FTP client. To connect to a FTP site using web browser, enter
                 the URL of the FTP site; ftp://ftpserver/pathname. For example, to connect to ‘ftp.sunet.se’, type the URL
                 ftp://sunet.se.

                 Downloading and Uploading

                 Downloading refers to transfer of file from a remote computer to the host computer. FTP helps to make
                 a directory on a computer connected to the Internet and to transfer a file from that directory on another
                 computer on the Internet.

                 The files can be downloaded from a FTP site even by an anonymous user. To download, the browser asks
                 for a name and location on the local computer to save that file.


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