TCP segment structure in Computer Networks - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Identify the purpose of the Sequence Number field in a TCP segment

What is the main role of the Sequence Number field in a TCP segment?

A It indicates the order of bytes sent from sender to receiver to ensure data is reassembled correctly.

B It contains the checksum value used for error detection in the segment.

C It specifies the maximum size of the TCP segment that can be received.

D It signals the type of service requested for the segment in the network.

💡 Hint

Think about how TCP ensures data arrives in the right order.

The Sequence Number field helps the receiver put the data back in the correct order by numbering each byte sent.

📋 Factual

intermediate

Size of the TCP Header without options

What is the size in bytes of a standard TCP header without any options?

A 40 bytes

B 8 bytes

C 20 bytes

D 32 bytes

💡 Hint

Recall the fixed length of the TCP header before options are added.

The standard TCP header is 20 bytes long when no options are included.

🔍 Analysis

advanced

Determine the effect of the Window Size field in TCP flow control

How does the Window Size field in a TCP segment affect data transmission?

A It contains the port number of the destination application.

B It specifies the total size of the TCP segment including header and data.

C It indicates the priority level of the segment in the network queue.

D It controls how many bytes the sender can transmit before waiting for an acknowledgment, managing flow control.

💡 Hint

Consider how TCP prevents overwhelming the receiver with too much data at once.

The Window Size tells the sender how much data it can send before needing an acknowledgment, helping to avoid congestion.

❓ Comparison

advanced

Compare the roles of the Acknowledgment Number and Sequence Number fields

Which statement correctly compares the Acknowledgment Number and Sequence Number fields in a TCP segment?

A Sequence Number is used only in connection setup; Acknowledgment Number is used only in connection teardown.

B Sequence Number indicates the byte number sent; Acknowledgment Number indicates the next expected byte from the other side.

C Sequence Number shows the total bytes received; Acknowledgment Number shows the total bytes sent.

D Sequence Number and Acknowledgment Number both indicate the same byte number for error checking.

💡 Hint

Think about how TCP tracks sent data and confirms receipt.

The Sequence Number marks the byte position sent; the Acknowledgment Number tells the sender which byte the receiver expects next.

❓ Reasoning

expert

Identify the error caused by an incorrect Checksum field in a TCP segment

What happens if the Checksum field in a received TCP segment does not match the computed checksum?

A The segment is discarded because it is considered corrupted during transmission.

B The segment is accepted but flagged for retransmission later.

C The segment is forwarded to the application layer without error checking.

D The segment triggers a connection reset immediately.

💡 Hint

Consider how TCP ensures data integrity before processing.

If the checksum does not match, TCP treats the segment as corrupted and discards it to avoid passing bad data.