14,057 views
44 votes
44 votes

Which of the following functionality must be implemented by a transport protocol over and above the network protocol?

  1. Recovery from packet losses
  2. Detection of duplicate packets
  3. Packet delivery in the correct order
  4. End to end connectivity

7 Answers

Best answer
76 votes
76 votes

Answer(D) TCP and UDP are transport layer protocols.

Question is asking which service must be provided by transport layer so that source can successfully communicate to destination. UDP is a connection-less protocol but it's a transport layer protocol so that from here we can say that reliability is not a service that MUST be provided by transport layer protocols. with that same argument cut all those options in which such a service is mentioned which UDP doesn't provide so only (D) remain so it's the answer..

other way to answer is ' for Process to Process delivery transport layer service is MUST otherwise there is no way to deliver the data to right process'.. if reliability is in danger data can survive (Data link layer also take care about errors so we can compromise error recovery at transport layer), if there are duplicate packets , yet data can survive ,only bandwidth is wasted, if packets are delivered out of order data can survive but if data of process A is delivered to process B , data can't survive.... "to Assigning port numbers" Transport layer service is MUST...

edited by
27 votes
27 votes
End to end connectivity is the required functionality provided by Trnasport protocol. UDP of transport layer protocol that doesn't implement other three functionalities, they are implemented only in TCP.
6 votes
6 votes
Service point addressing is an important functionalities of transport layer That's why End to End connection or Socket to Socket connection is must gifted properties of Transport layer.
5 votes
5 votes
D. Transport layer protocol is called end to end connecting layer.
Answer:

Related questions

29 votes
29 votes
5 answers
1
27 votes
27 votes
4 answers
2
Kathleen asked Sep 21, 2014
13,758 views
Match the following:$$\begin{array}{llll} \text{(P)} & \text{SMTP} &(1)& \text{Application layer} \\ \text{(Q)} & \text{BGP}& (2) & \text{Transport layer} \\ \text{(R)}...