Module 3 Flashcards
Protocol suite
nodes and base stations
- wireless hardware used in base stations
- nodes or clients , devices that connect to the base station
- base stations are the routers or gateway
IoT protocol
- common language that allows devices to interact with other IoT devices
- IoT protocol lay down standards that adopted in every IoT ecosystem for proper functioning and avoid security threats.
iot protocol model
(explain each layer)
->analytics/visualization layer
->application/integration layer
->data/database layer
->network layer
->physical/device layer
three layer protocol suite
(explain each layer)
-> application layer
-> network layer
-> perception layer
five layer protocol suite
(explain each layer)
-> business layer
-> application layer
-> processing layer
->transport layer
-> perception layer
functions of physical layer
(explain points)
- Representation of bits
- data rate 3. synchronization
- interface 5. topologies
- line configuration
- transmission modes
link layer
includes protocol that defines communication between local network nodes which fulfill the purpose of maintaining link states between the local nodes
BLE
- Bluetooth low energy
- BLE is an intelligent and a low power version of Bluetooth wireless technology
- not suitable for sending real time data
- short range communication protocol with PHY and MAC layer
benefits of BLE
- lower implementation costs
- multi-vendor interoperability
- enhanced range
- much improved pairing speed
application of BLE
- battery powered devices developed for industries like healthcare, fitness, security and home industries
features of BLE
- Location detection accuracy
- proximity detection
- power consumption
BLE architecture
- BLE follows master/slave technology . slave node sent the advertising frame to discover one or more dedicated advertisement channels. master nodes sense this advertisement channels to find slaves and connect them
- BLE always remains in sleep mode except when the connection between devices is intiated.
LoRAWAN
- Low Power Wide Area Networking communication protocol
- Low power, wide area networking protocol built on top of the LoRa radio modulation technique
- architecture- star to stars topology
application of LoRAWAN/LoRa
usage in smart cities and industrial spaces because it is an affordable long range , bi-directional communication protocol with very low power consumption
3. device can run for 10 years on a small battery
LoRa
1.radio manipulation technique that is essentially a way of manipulating radio waves to encode information.
2. physical layer protocol that supports long range communication at the cost of a narrower bandwidth
why LoRAWAN?
- ultra low power 2. long range
- deep indoor penetration
- license free spectrum
- geolocation 6. high capacity
- public and private deployments
- end to end security 9. roaming
- firmware updates over air
- low cost
architecture LoRAWAN
- star to stars topology
[end to end nodes]->[gateway]->[network server]->[application server]
characteristics of LoRAWAN technology
- Long range communication
- long range battery duration upto 10 years
- low cost for devices and maintenance
- license free radio spectrum nut regulations apply
- Low power
Security in LoRA
1.LoRA achieved by implementing security at two different layers:
-> one for the network
-> one for the application
2. to achieve the required levels of security for LoRa networks, several layers of encryption have to be employed.
use cases of LoRaWAn
- vaccine cold chain monitoring
- animal conservation
- dementia patients
- smart farms
- water conservation
- food safety 7. smart waste bins
- smart bikes 9. airport tracking
- efficient workspace
- cattle health 12. LoRa in space
network layer
this layer is divided into two parts
->routing layer: sends packages from origin to destination
-> encapsulation layer: largely responsible for creating packages
transport layer
- main role is to provide communication services directly to the application processes running on different hosts.
- TCP,UDP two transport layer protocols that provide different set of services to the network layer
- application communicates to either one of these protocols. These applications can read and write to the transport layer. So communication is a two way process
services offered by transport layer
- end to end delivery
- addressing 3. reliable delivery
- flow control 5. multiplexing
multiplexing
- upward multiplexing: multiple transport layer connections use the same network connection
- downward multiplexing: means one transport layer connection uses the multiple network connections
MQTT
- Message Queue Telemetry Transport
- used for machine to machine communication
- simple and lightweight messaging protocol , uses publish/subscribe model
- supports messaging between devices to the cloud and the cloud to the device
why is MQTT important?
(explain points)
- lightweight and efficient
- Scalable 3. reliable 4. secure
- well-supported
MQTT client
- client sends messages then its a publisher , if it receives messages then its a subscriber are the two roles of a client
- a device is a client if it opens a network connection to the server, publishes messages that other clients want to see, subscribes to a message
MQTT broker
backend system which coordinates messages between the different clients. broker include receiving and filtering messages, identifying clients subscribed to each message
MQTT connections
- clients and brokers begin communicating by using an MQTT connection. Clients initiate connection by sending a CONNECT message to the MQTT broker.
- the broker confirms that a connection has been established by responding with a CONNACK message
- clients never connect with each other, only with broker
MQTT architecture
[Publisher]->(message)->[MQTT Broker]->(message)->[subscriber]
in the middle there is a central server or broker that acts as a mediator. Each incoming message is filtered by the broker who then send them to appropriate customers
QoS 0
- provides bare minimum of data transfer.
- Every message is transmitted to a user only once at this stage with no verification
QoS 1
- This broker tries to send the message and then checks for the user’s approval reply
- with no verification received in a certain amount of time, the message is resent.
- if broker does not get user’s confirmation on time, message maybe sent to user multiple times using this approach
QoS 2
- four step handshake used by the client and broker to ensure that information is received and only once
- optimum solution in cases where communication are inconsistent but links aren’t as resource- constrained
CoAP
- Constrained Application protocol
- a lightweight protocol for M2M communication
- particularly used in IoT scenarios where constrained devices and networks are involved
features of CoAP
(explain points)
- lightweight
- request-response model
- RESTful interaction
- reliable and unreliable messaging
- resource discovery
- security
application of CoAP
(explain points)
- smart home automation
- industrial monitoring and control
- asset tracking
- environmental monitoring
- smart agriculture
- healthcare and wearable devices
CoAP vs MQTT
to be gone through along with diagram
