Which three statements characterize the transport layer protocols?

Question

Hi, guys. Recently, I've prepared one test about network.

For this time, I found one question but I don't know the answer.

The question is below.

Which three statements characterize the transport layer protocols?(Choose three.)

1. TCP and UDP port numbers are used by application layer protocols.

2. TCP uses port numbers to provide reliable transportation of IP packets.

3. UDP uses windowing and acknowledgments for reliable transfer of data.

4. TCP uses windowing and sequencing to provide reliable transfer of data.

5. TCP is a connection-oriented protocol. UDP is a connectionless protocol.

I make sure that No 4, 5 are correct.

But I'm confusing what is the answer between No1 and No2.

Please give me the answer if you know this question.

Thank you for reading this article.

Answer 1

1) Is a correct statement

2) Is incorrect, since port numbers do not provide reliability, they are only used in the application layer

3) is incorrect because UDP is a broadcast protocol with no acknowledgemement of packets

As you know, TCP uses 3-way handshake and is connection oriented; TCP gives guaranteed delivery, flow control and windowing. That's why TCP packets use sequence numbers, acknowledge numbers, etc.; UDP packets don't use sequence numbers. UDP is connectionless, which means best effort delivery. Some TCP protocols are POP3, SMTP, FTP, HTTP etc. whereas some UDP protocols are TFTP, DHCP, SNMP etc.

Answer 2

#2 looks correct but it is wrong

#1 is correct...cos its all about sockets....which the applications use...like windows media player