Communication And Networking Principles And Technologies For IoT

Question 1

How does a typical architecture of IoT device looks like?

Answer 1

Sensors will be used to sense environment - will be sent to the microcontroller, which is run with help from battery and memory. Battery will help microcontroller transmit data further.

Question 2

Discuss the three basic tasks for an IoT decice.

Answer 2

Sensing: observe the environment. (Temperature, humidity, pressure, noise, etc)

Computation: process the sensed data (done with help from the microcontroller. Usually C-like languages used for coding the microcontroller, fx Arduino)

Communication: transmit the data wirelessly (IoT transmitters could be ZigBee, LoRa. Typically low data rates, ~100 kbit/s)

Question 3

Discuss what elements does a lot of power consumption? How do we reduce the consumption?

Answer 3

Transmitting and receiving data have high power consumption. LED is almost as high as receiving data. Reduce the power consumption by using sleep or standby. (Either periodicly or by trigger)
Communcation is power hungry. Computation and sensing also require some power.

Question 4

Pros and cons of using a low duty cycle for power consumption?

Answer 4

Pro: Ensures long life
Con: Latency in data delivery, control and management of the network.

Question 5

A general IoT structure consist of..

Answer 5

• The IoT device monitered and active
• A network creates end-to-end communication between machines
• An application server (responsable for running server side code) which processes data when demanded, to the machines.

Question 6

Come with examples of Wired access networks, and discuss pros/cons.

Answer 6

Wired - cable between sensors: Cable, Optical, etc

Pros: Very reliable, very high rates, little delay, secure

Cons: Expensive to set up, vandalism, not scalable, no mobility.

Question 7

Come with examples of wireless capillary access networks, and discuss pros/cons.

Answer 7

Wireless capillary - shared short-range link/network: IEEE 802.11, Wireless M-BUS, etc.

Pros: Cheap to set up, generally scalable, low power.

Cons: Short-range, low rates, weak security, lack of universal infrastructure. Multi-hop not a solution

Question 8

Come with examples of Low power Wide area access networks, and discuss pros/cons.

Answer 8

Low power wide area: LoRa, SigFox

Pros: Cheap to set up, generally scalable, low power.

Cons: Short range, low rates, weaker security, lack of universal infrastructure. Multi-hop not a solution

Question 9

Discuss Satelite access network.

Answer 9

Satelite - serves as a relay between device and gateway: Satelite M2M communication.
High returns per device.

Question 10

What is the ratio (of control information vs data in human-oriented communications) in a short IoT packet?

Answer 10

Almost 50/50 ratio. We wish to have more data in human-oriented communications (which we have in larger packets)

Question 11

Where to we see the use of uplink and downlink traffic in IoT?

Answer 11

Most IoT traffic is uplink oriented. For instance when sending data of sensor readings.
Downlink mostly used for signaling and network control functions.

Question 12

Discuss real-time control IoT traffic.

Answer 12

Have already-defined cycles. Thereby easy to schedule (because they are static), and all devices should be synchronous.

Question 13

Discuss Periodic monitoring IoT traffic.

Answer 13

Devices continuosly observe the enviroment. Reporting is performed regular periods, size vary from miliseconds to hours.

Question 14

Discuss event detection IoT traffic.

Answer 14

Devices continuosly observe the enviroment. Will alarm the user about some event, and reported instantly. Example: Too high temperature, detection of movement.