Quiz4 CN

Packetizing at the network layer involves

• Encapsulating the payload at the source

• Adds a header that contains the source and destination information

• Decapsulating the payload at the destination

• All of the choices are correct

Routers in the path are not allowed to ___________________________.

• fragment the packet they receive

• decapsulate the packet

• change source or destination address

• All of the choices are correct

The network layer in the Internet provides _________________.

• comprehensive error and flow control

• limited error control, but no flow control

• comprehensive error control but limited flow control

• All of the choices are correct

In a virtual-circuit approach, the forwarding decision is based on the value of the _____________ field in the packet header.

• source address

• destination address

• label

• None of the choices are correct

In a datagram approach, the forwarding decision is based on the value of the _____________ field in the packet header.

• source address

• destination address

• label

• None of the choices are correct

The performance of a network can be measured in terms of ________.

• delay

• throughput

• packet loss

• all of the choices are correct

Transmission delay (time) is the ratio of ______________________.

• transmission rate to packet length

• transmission rate to distance

• packet length to transmission rate

• processing time to transmission rate

Propagation delay (time) is the ratio of ______________________.

• transmission rate to propagation speed

• propagation speed to distance

• packet length to propagation speed

• distance to propagation speed

When the load in the network reaches the network capacity, the packet delay ___________ and the network throughput reaches ______________.

• increases sharply; its minimum

• increases sharply; its maximum

• decreases sharply; its minimum

• decreases sharply; its maximum

In open-loop congestion control, policies are applied ____________________.

• to prevent congestion before it happens

• to alleviate congestion after it happens

• to either prevent congestion before it happens or to alleviate congestion after it happens

• None of the choices are correct