Wireless Networks Quiz 3

Which of the following are true IEEE 802.11n-2009?

• uses OFDM and MIMO

• known as WiFi 4 standard

• uses multiple antennae

• cannot transmit and receive simultaneously

The standard IEEE 802.15.4 has the following features -

• Very little power consumption.

• Low-cost and low-speed communication.

• Very High bandwidth

• Ideal for long distance communication

IEEE 802.15.4 -

• uses Carrier Sense Multiple Access

• uses TIme Division Multiple Access

• does not support secure communication

• controls power consumption and data rate

How is WSN MAC different from MAC?

• WSN MAC requires high throughput

• WSN MAC requires low error rates

• WSN MAC requires low protocol overhead

• WSN MAC requires energy-efficiency

Which of the following are problems specifically for WSN?

• Collisions

• Overhearing

• Idle listening

• Protocol Overhead

Which of the following medium access categories are not feasible for large undivided networks?

• Centralized Medium Access

• Schedule-based Medium Access

• Contention-based Medium Access

• Distributed Medium Access

Sensor-MAC is a -

• Synchronous type MAC

• Duty Cycle based MAC

• Centralized MAC

• Randomized MAC

The given figure is a node distribution of a WSN. Which of the labeled nodes have the highest probability of being depleted of energy when S-MAC is used?

• A

• B

• C

• D

Which of the following WSN protocols use RSSI sampling to reduce energy while detecting channel activity?

• S-MAC

• B-MAC

• LEACH

• RI-MAC

What are the pre-requisites of using LEACH?

• Presence of central sink.

• Sparse network of nodes.

• Ability to communicate with sink.