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(a) TCP/IP (Transmission Control Protocol/Internet Protocol)

TCP is one of the main protocols in TCP/IP networks. The IP protocol deals only with
packets but TCP enables two hosts to establish a connection and exchange streams of data.
TCP works with the Internet Protocol (IP), which defines how computers send packets of
data to each other. The packets are delivered not in a sequential order; instead, they are
delivered randomly. Now, TCP at the receiver side collects all packets and arranges them
in a sequential order. TCP is a reliable stream delivery service that guarantees that all
bytes received will be identical with bytes sent and in the correct order. Since packets are
transferred over many networks and, thus, not reliable, a technique known as positive
acknowledgement with retransmission is used to guarantee reliability of packet transfers.

(b) IP (Internet Protocol)

IP is the primary protocol present in the internet layer of the internet protocol suite. It
is responsible for delivering packets from the source host to the destination host based
on the IP addresses mentioned in the packet headers. IP forwards each packet based on
a four byte destination address (the IP number). The packets are moved randomly from
source to destination, which are then assembled in a sequential order at the destination
computer. IP stores destination addresses in the form of IP addresses so that the packets
will move to the destined address only by following the shortest route.

(c) FTP (File Transfer Protocol)
FTP is the simplest and most secure way to exchange files over the internet. The main
objectives of FTP are:

• Transmitting and sharing of files (computer programs and/or data).
• Indirect or implicit use of remote computers.

• To shield a user from variations in file storage systems among different hosts.
• To transfer data reliably and efficiently.

• FTP uses the internet’s TCP/IP protocols to enable data transfer.

FTP is most commonly used to download a file from a server using the internet or to
upload a file to a server (e.g., uploading a web page file to a server).
While sharing files from one system to another, we may encounter several problems—
two systems may have different directory structures, two systems may have different file-
naming conventions, or two systems may have different ways to represent text and data.
All these problems are solved by FTP.
Computer Science with Python–XII 8.32 information sharing.
CTM: File transfer protocol is used to transfer files from server system to requesting node, primarily for

PPP (Point-to-Point Protocol)
(d)

PPP is the most commonly used data link protocol. It is a protocol used to establish a direct
connection between two nodes. It can provide connection authentication, transmission
encryption and compression. It is used to connect the Home PC to the server of ISP.
The communication takes place through high speed modem. PPP is used to connect