Question

Answer the Following

- Suppose you are designing an application. This application of yours is time sensitive (i.e., media application). Which protocol would you use UDP or TCP? Why?

- Why do HTTP, FTP, SMTP, and POP3 run on top of TCP rather than on UDP?

- Explain initial transfer of home page and how many RTT required?

- In terms of RTT, how quickly your browser downloads the base page for www.hamburger.com and all the embedded objects under following conditions:

1. One connection per item, with up to 4 concurrent connections.
2. A single persistent, non-pipelined connection.
3. A single pipelined connection.

Answer 1

Hey buddy, i have spent much time to explain these terms in simple form so, if you got something from it, give it a upvote. Thank you.

1. Suppose you are designing an application. This application of yours is time-sensitive (i.e., media application). Which protocol would you use UDP or TCP? Why?

The Internet makes two transport protocols available to its applications that are UDP(User Datagram Protocol) and TCP(Transmission Control Protocol).
So the best protocol for designing application(which is also a time-sensitive) is UPD because
- UDP is the best for time-sensitive communications, including (VoIP) voice over internet protocol, (DNS)domain name system lookup, and video or audio. UDP avoids the overhead of such processing in the protocol stack. Time-sensitive applications often use UDP protocol because dropping packets is preferable to wait for packets delayed due to retransmission, which may not have other options in a real-time system.
- Voice and video traffic are sent using this protocol because they are both time-sensitive and designed to handle a medium level of loss. For example, the voice over IP, which is used by many internet-based telephone services, operates over UDP. This is because a static phone conversation is preferable to one that is crystal clear but mostly delayed for this.

2. Why do HTTP, FTP, SMTP, and POP3 run on top of TCP rather than on UDP?

- TCP is the most sought after transmission protocol due it’s reliability and ubiquity, such that it has now become the underlying protocol for almost all network transmissions. UDP being a connectionless transport protocol, there can be no guarantee of reliable data transmission.
- TCP provides all application data be received in the correct order, also without gaps, but UDP does not do that. So, HTTP, FTP, SMTP, and POP3 run on top of TCP rather than on UDP.
- Its feature of handling small queries from a huge number of clients is useful for servers. Hence this is the reason why TCP is the most commonly used application protocol for HTTP, FTP, SMTP, IMAP, POP3.
- UDP is a fire and forgets protocol, but extremely quick, and useful for computers in a local network. UDP is a connection-less transport protocol, with minimum overhead.

3. Explain the initial transfer of the home page and how many RTT required?

- A home page is a webpage that serves as the starting point of the website. It is the default webpage that loads when you visit a web address for the first time or when you load
- So what is Round-trip time: Round-trip time (RTT) is the period in milliseconds (ms) it takes for a network request to go from a starting point to a destination and back again to the starting point.
the RTT or Round-trip time required for the home page is that 2RTT is the initial required for connection: one for TCP connection and one for HTML base file.
Formula : Total time=2RTT + transmit time

4. In terms of RTT, how quickly your browser downloads the base page for www.hamburger.com and all the embedded objects under the following conditions:

a. One connection per item, with up to 4 concurrent connections.
- 7 RTT or 8 RTT Because
(for this 3 RTT required to fetch the first HTML page and 2 RTT to fetch each of the embedded images and lastly 3 RTT to fetch other images)

b. A single persistent, non-pipelined connection.
- 10 RTT Because
(3 RTTs to fetch the first HTML page. with persistent and non-pipelined connection, the browser can only fetch one item at a time and with all of the embedded images so 1+1+1+1+1+2 = 7 RTT + 3 RTT = 10 RTT)

c. A single pipelined connection.
- 7 RTT Because
( for single pipelined connection 3 RTT to fetch the first HTML page. and 4 RTT for embedded images to transfer, So 4 RTT + 3RTT = 7 RTT).