Application Layer Protocols MCQ Quiz in मल्याळम - Objective Question with Answer for Application Layer Protocols - സൗജന്യ PDF ഡൗൺലോഡ് ചെയ്യുക

The correct answer is Option 2.

Concept:

The most commonly used Email protocols on the internet – POP3, IMAP, and SMTP. 

• Post Office Protocol 3 is the most commonly used protocol for receiving email over the internet. This standard protocol, which most email servers and their clients support, is used to receive emails from a remote server and send them to a local client.
• Internet Message Access Protocol is a protocol for accessing email or bulletin board messages from a mail server or service. IMAP allows a client e-mail program to access remote message stores as if they were local.
• The Simple Mail Transfer Protocol is the industry standard for sending emails over the Internet.

The correct answer is (ii), (iii), and (iv).

TCP / IP model is a communications protocol to interconnect network devices on the internet. TCP / IP model has 4 layers.

The four layers are as follows:

• Application layer 
• Transport layer
• Internet layer
• Network access layer

The presentation layer is absent in the TCP / IP model.

Various Protocols and the layers on which they work in TCP/IP model is shown:

• TCP/IP model has 4 layers while the OSI model has 7 layers.

• These 7 Layers of OSI are the application layer, the presentation layer, the session layer, the transport layer, the network layer, the data-link layer, and the physical layer.

• The presentation layer is absent in the TCP/IP model while it is present in the OSI model.

Explanation:

• Q makes a TCP connection with S
• First request for the webpage when this request is received by S
• Second request to S for picking up that image so at least 2 HTTP request are needed.
• Above two request are done using HTTP version 1.1 ( HTTP persistent connection )
• HTTP Persistent connection can make several requests on the same server.
• Here TCP may close the TCP connection.
• So at least 2 HTTP request are enough and 1 TCP connection is sufficient for desired goal.

Hence option 2 is the correct answer.

Concept:

A mail server is the computerized equivalent of your friendly neighborhood mailman. Every email that is sent passes through a series of mail servers along its way to its intended recipient

Mail servers can be broken down into two main categories:

• Outgoing mail servers
• Incoming mail servers.

Outgoing mail servers are known as SMTP, or Simple Mail Transfer Protocol, servers. Incoming mail servers come in two main varieties. POP3, or Post Office Protocol, version 3, servers are best known for storing sent and received messages on PCs’ local hard drives. IMAP, or Internet Message Access Protocol, servers always store copies of messages on servers. 

The correct answer is "option 3".

CONCEPT:

DNS, which stands for Domain Name System, maps domain name into Internet Protocol (IP) address. 

IP → Domain name

Hence, the DNS maps the IP addresses to a hierarchy of domain names.

Additional Information

In reverse DNS lookup, Internet Protocol (IP) addresses are mapped into domain names.  

Domain name→ IP

The correct answer is international organizations.

• The domain name int in the Domain Name System (DNS) is used in international organizations.

Additional Information

The correct answer is Persistent TCP connection, non-persistent TCP connection.

Key Points

• File Transfer Protocol or FTP is an application layer protocol and is used to communicate and transfer files between different systems on a TCP/IP protocol over the internet. It is a standard protocol for transmitting files from one host to another.
• It is also used for downloading files from servers to computers. Two computers can have different file conventions and different ways to represent data. This creates a problem while transferring.
• FTP overcomes these issues by establishing two connections between hosts. One is used for data transfer and the other connection is used for the control connection.
• For sending the actual file, the data connection is used. This connection is made between the data transfer process. For this non-persistent connection is used.
• Through control connection, we can send control information like user credentials, commands to change the remote directory, commands to retrieve and store files etc. For this FTP uses a persistent connection. Hence Option 2 is correct.

Additional Information

• FTP is one of the fastest and most efficient ways to transfer files from one computer to the other. The size limit of the file to be transferred is 2GB.
• Persistent connection or HTTP persistent connection is a communication channel that remains open for further HTTP requests and responses.
• Non-persistent connection is a channel that maintains no information about the previous requests.

The correct answer is SMTP.

Key Points

• SMTP is used for sending emails, whereas POP is used for receiving emails.
• SMTP stands for Simple Mail Transfer Protocol.
• POP stands for Post Office Protocol.
• SMTP is a set of communication guidelines that allow the software to transmit electronic mail over the internet.
• Post Office Protocol is an application-layer Internet standard protocol used by e-mail clients to retrieve e-mail from a mail server. 

Key Points 

SMTP stands for Simple Mail Transfer Protocol. SMTP is used when email is delivered from an email client, such as Outlook Express, to an email server or when email is delivered from one email server to another. SMTP uses port 25.

POP3 stands for Post Office Protocol. POP3 allows an email client to download an email from an email server. POP3 normally uses port 110.

IMAP stands for Internet Message Access Protocol. It is a protocol that an email client can use to download email from an email server. IMAP requires more disk space on the server and more CPU resources than POP3, as all emails are stored on the server. IMAP normally uses port 143.