Application Layer

Question 1

Consider different activities related to email:

m1: Send an email from a mail client to a mail server
m2: Download an email from mailbox server to a mail client
m3: Checking email in a web browser

Which is the application level protocol used in each activity?

• m1: HTTP m2: SMTP m3: POP
• m1: SMTP m2: FTP m3: HTTP
• m1: SMTP m2: POP m3: HTTP
• m1: POP m2: SMTP m3: IMAP

Question 2

Identify the correct order in which the following actions take place in an interaction between a web browser and a web server.

1. The web browser requests a webpage using HTTP.
2. The web browser establishes a TCP connection with the web server.
3. The web server sends the requested webpage using HTTP.
4. The web browser resolves the domain name using DNS.

• 4,2,1,3
• 1,2,3,4
• 4,1,2,3
• 2,4,1,3

Question 3

A graphical HTML browser resident at a network client machine Q accesses a static HTML webpage from a HTTP server S. The static HTML page has exactly one static embedded image which is also at S. Assuming no caching, which one of the following is correct about the HTML webpage loading (including the embedded image)?

• Q needs to send at least 2 HTTP requests to S, each necessarily in a separate TCP connection to server S
• Q needs to send at least 2 HTTP requests to S, but a single TCP connection to server S is sufficient
• A single HTTP request from Q to S is sufficient, and a single TCP connection between Q and S is necessary for this
• A single HTTP request from Q to S is sufficient, and this is possible without any TCP connection between Q and S

Question 4

In one of the pairs of protocols given below, both the protocols can use multiple TCP connections between the same client and the server. Which one is that?

• HTTP, FTP
• HTTP, TELNET
• FTP, SMTP
• HTTP, SMTP

Question 5

Which one of the following statements is NOT correct about HTTP cookies?

• A cookies is a piece of code that has the potential to compromise the security of an Internet user
• A cookie gains entry to the user’s work area through an HTTP header
• A cookie has an expiry date and time
• Cookies can be used to track the browsing pattern of a user at a particular site

Question 6

Consider the following statements:
I. telnet, ftp and http are application layer protocols.
II. EJB (Enterprise Java Beans) components can be deployed in a J2EE (Java2 Enterprise Edition) application server. 
III. If two languages conform to the Common Language Specification (CLS) of the Microsoft.NET framework, then a class defined in any one of them may be inherited in the other.
Which statements are true?

• l and II only

• II and III only

• l and III only

• I, II and III

Question 7

Which of the following is/are example(s) of stateful application layer protocols?

(i)  HTTP
(ii) FTP
(iii) TCP
(iv) POP3 

• (i) and (ii) only
• (ii) and (iii) only
• (ii) and (iv) only
• (iv) only

Question 8

An application layer is an abstraction layer that specifies the shared communications protocols and interface methods used by hosts in a communications network. Consider the following statements regarding various application layer protocols: (S1) : BOOTP is a Host initialization protocol which is implemented using the Transmission Control Protocol (TCP) as transport protocol. (S2) : Domain Name System (DNS) is Networking support protocol which uses User Data Protocol (UDP) as transport protocol. (S3) : Simple Network Management Protocol (SNMP) is a Remote host management protocol which uses Transmission Control Protocol (TCP) as transport protocol. Which of the following option is True?

• Only (S1) and (S2) are not correct.
• Only (S1) and (S3) are not correct.
• Only (S2) and (S3) are not correct.
• All statements (S1), (S2), and (S3) are correct.

Question 9

Which of the following protocol is used for transferring electronic mail messages from one machine to another?

• TELNET
• FTP
• SNMP
• SMTP

Question 10

Which of the following protocols is used by email server to maintain a central repository that can be accessed from any machine ?

• POP3
• IMAP
• SMTP
• DMSP