Computer Networks

1. The core function of the Data Link Layer that involves adding a header and trailer to a network layer packet is called

• Encapsulation

• Modulation

• Framing

• Segmentation

2. Which of the following is NOT a design issue of the Data Link Layer?

• Framing

• Flow control

• Error control

• Routing

Which technique is commonly used for error detection in data link layer?

• Checksum

• Cyclic Redundancy Check (CRC)

• Hamming Code

• Parity Bit

Hamming Code is primarily used for:

• Error Detection only

• Error Correction only

• Both Error Detection and Correction

• Flow Control

In Stop-and-Wait protocol, the sender can send:

• Multiple frames at once

• One frame at a time and wait for acknowledgment

• A window of frames without waiting

• Only control frames

In Go-Back-N ARQ, if frame k is lost, the receiver

• Requests retransmission of only frame k

• Accepts all frames after k

• Discards all frames after k and waits for retransmission of k

• Sends cumulative acknowledgment

Selective Repeat ARQ is more efficient than Go-Back-N because

• It retransmits only the erroneous frames

• It requires fewer acknowledgments

• It does not need sequence numbers

• It avoids timeouts

Which of the following is NOT a multiple access protocol

• ALOHA

• CSMA

• TDMA

• ARP

The main advantage of a switched LAN over a hub-based LAN is

• Higher bandwidth per device

• No collisions

• Dedicated point-to-point links

• All of the above

Link Virtualization allows

• Multiple virtual links over a single physical link

• Only one-to-one dedicated physical connections

• Removal of congestion in the Internet

• Hardware replacement without downtime