CN-2

What is the essential property of a channel that makes it "wirelike"?

• Bits are delivered in reverse order.

• Bits are delivered in random order.

• Bits are delivered in exactly the same order in which they are sent.

• Bits are delivered with a delay.

What is one of the functions of the data link layer?

• Encrypting data for security.

• Providing a well-defined service interface to the network layer.

• Compressing data to save space.

• Managing user access to the network.

Which issue does the data link layer address to prevent slow receivers from being overwhelmed?

• Data encryption

• Data compression

• Regulating the flow of data

• Increasing data speed

What is a limitation of communication circuits mentioned in the text?

• They have infinite data rates.

• They never make errors.

• They have a nonzero propagation delay.

• They always deliver data instantly.

What does the data link layer do with packets from the network layer?

• Encrypts them

• Encapsulates them into frames

• Compresses them

• Discards them

Which service involves sending independent frames without acknowledgment from the destination machine?

• Acknowledged connectionless service

• Unacknowledged connectionless service

• Acknowledged connection-oriented service

• Connection-oriented service

What is a key characteristic of the acknowledged connectionless service?

• Uses logical connections

• Frames are individually acknowledged

• No frames are acknowledged

• Requires a connection setup

For which scenario, the unacknowledged connectionless service be appropriate?

• High error rate

• Low error rate

• High bandwidth requirement

• Low bandwidth requirement

In connection-oriented service, what happens in the first phase?

• Frames are transmitted

• Connection is released

• Connection is established

• Data is encrypted

How does connectionless service differ from connection-oriented service?

• It guarantees each frame is received

• It uses a reliable bit stream

• Lost acknowledgements can cause packets to be sent multiple times

• It establishes a connection before data transfer