Page 183 - Computer_Science_F5

Computer Science Connection: The client connects to the FTP ensures secure and reliable file
server using FTP and authenticates with transfers between the client and server.
a username and password.

(iii) SMTP (Simple Mail Transfer
Uploading: The client selects a file to Protocol)
FOR ONLINE READING ONLY
send to the server, which stores it in a
specified location. This protocol is utilised for sending
emails and works together with other
protocols like IMAP and POP3 to
Downloading: The client requests a file manage the delivery and retrieval of
from the server, which sends it back for emails. Figure 3.27 demonstrates how
the client to save locally. SMTP works.

Is recipient in my list of recipient?
NO. Send elsewhere SMJP/POP3
server
SMJP/POP3
server

Sender
Figure 3.27: Implementation of SMTP

(i) DNS (Domain Name System)
This protocol translates human-readable domain names (such as, www.tie.go.tz)
into IP addresses that computers use to identify each other on the network.

(ii) DHCP (Dynamic Host Configuration Protocol)

Automatically assigns IP addresses and other network configuration parameters to
devices on a network, enabling them to communicate effectively.

Activity 3.9:

Accessing web pages to explore the Application layer
Aim: To understand how the application layer facilitates web browsing
and data exchange between client computers and web servers.

Materials: Computer lab access or a personal computer/laptop; Internet access;
and Web browser (such as Chrome, Firefox, Safari)

Instructions
Step 1: Open a web browser on a networked computer.

174
for Advanced Secondary Schools

Computer Science Form 5.indd 174 23/07/2024 12:33