Internet das coisas

Disponível somente no TrabalhosFeitos
  • Páginas : 6 (1476 palavras )
  • Download(s) : 0
  • Publicado : 8 de abril de 2013
Ler documento completo
Amostra do texto
Internet of Things - An Introduction

Dr. P.C. Jain, Dr. Arti Noor, Vinod Sharma

School of Electronics

Outline:
• • • • • • • • Introduction Wireless Sensor Network Low Power WPAN IPv6-6LoWPAN Energy Harvesting Applications Ubiquitous Computing Group Activities Conclusions

Introduction
• Internet of Things (IoT) represented as “Worldwide network interconnecting Things / objects” •Objects/Things could be Books, Cars, Electrical appliances, Food etc.

• IoT will become third IT revolution after mobile phones and PCs

Cost

Miniaturization

Internet of Things

• * * * •

IoT covers communication between Things–to–person, Things-to-things, Machine-to- machine It will have billions or trillions objects communicating with one another It has become possible dueto advances in Micro-electronics Wireless communication and Information technology

• * * *

• Objects of IoT Interact with one another to perform action on behalf of people • IoT will improve ultimately the quality of life • Objects will have their own IP addresses (IPv6 with 128 bit address) embedded in complex system • Objects are made smart * using micro-controllers and * usedtransceivers to communicate wirelessly

• Use RFID tags for identify the objects and its location • Use sensors to sense changes in physical environment • Use actuators to counteract on changes in physical environment

Antenna

Sensor

MicroController

Transceiver

Power PowerSupply Supply

Wireless Sensor Node

Sensor Node

Single Chip WSN Node

• Wireless Sensor Network (WSN)work under Low power Wireless Personal Area Network (LoWPAN) standard • For the same IEEE802.15.4 standard was introduced • Currently WSN have non-IP network protocol such as ZigBee, Bluetooth, or Ultra Wideband (UWB) where TCP/IP protocol is not used

IEEE802.15.4 Standard
This network is • Low cost • Long battery life (months to years) • Accommodate large sensor networks (Max. 65,535 nodes) •Provides high security using 128 bits AES • High reliability

• IEEE802.15.4 specify MAC and PHY layer

• PHY layer addresses robust modulation, transmission and receiving technique • MAC layer allocate medium to multiple nodes to not interfere with each other transmission

• IEEE802.15.4 has low data rate, low power consumption • Provides maximum data rate of 250kb/s at operatingfrequencies from 2.4 to 2.4835 GHz with 27 channels • In MAC layer channel access is carried out using Carrier Sense Multiple Access/ Collision Avoidance (CSMA/CA)

IPv6 – 6LoWPAN Standard
• To implement Internet over small devices, IETF came with “IPv6 over Low power Wireless Personal Area Network (6LoWPAN) standard as RFC 4944” • It specifies IPv6 datagram carried over IEEE802.15.4 frames • IPv6 hasenough address space to identify all the things in the world at the molecule level • IP protocols HTTP, TCP/IP are applied directly on things (sensor nodes)

IPv6 Internet Protocol: • IPv4 is a foundation for most of the Internet communication • It has 32 bit address (2^32 >4 Billion addresses) • Internet of Things will need billions to trillions of addresses • IPv6 has 128 bit address(2^128=10^38 address • IPv6 address written in 8 groups • 2001: 0db8 : 85a3: ……. :7334(h) • IPv6 header occupies 40bytes

1

4

12

32

48

60

64bit

Version Traffic Class

Flow label

Payload Length Source Address

Next Header

Hop Limit

Destination Address

IPv6 Header (40 Bytes)

Adaptation Layer:
• 6LoWPAN provides WSN node communication with IPv6 by puttingAdaptation layer above 802.15.4 MAC layer • Adaptation layer does IPv6 header compression, fragmentation and re-assembly of payload • IPv6 header is 40 byes long and payload up to 1280 bytes long • Maximum length of 802.15.4 data frame is only 127 bytes

6LoWPAN Protocol Stack

IEEE802.15.4 Header PHY MAC Header Security Header IPv6 Header TCP Header
6 25 Bytes 21 40
127 Bytes

20

TCP...
tracking img