Low-power IP: 6LoWPAN & Co

Low-power IP: 6LoWPAN & Co 1|Matthias Kovatschhttp://people.inf.ethz.ch/mkovatsc

Matthias [email protected]

Low-power IP: 6LoWPAN & Co.

Monday, 16 Jun 2014IoT MeetupToulouse, France

mailto:[email protected]


2

Environmental Monitoring

Smart Energy

Structural Health

Building Automation

Ambient Assisted Living

Real-time CityInformation

Logistics

Networked Embedded Systems Everywhere

technologicalislands


The IP-based Internet of Things

end-to-endIP connectivity

6LoWPANfor low-power

wireless


A Bit of History


Smart Dust in 2000

the advent of Wireless Sensor Networks


Academic research Sensor node platforms (“motes”) Event-driven operating systems Low-power MAC protocols Applications

Industrial specifications ZigBee WirelessHART

Focus on IEEE 802.15.4 First 802.15.4 specification in 2003 TI buys Chipcon (CC2420)

Wireless Sensor Networks

Mica2 (AVR)

Tmote Sky / TelosB (MSP430)

BTnode (AVR + Bluetooth)


First Proposals for Low-power IPv4 in 2003

A. Dunkels. Full TCP/IP for 8-bit Architectures.In Proceedings MobiSys, San Francisco, CA, USA, 2003

Z. Shelby, P. Mahonen, J. Riihijarvi, O. Raivio, and P. Huuskonen. NanoIP: The Zen of Embedded Networking.In Proceedings ICC, Anchorage, AK, USA, 2003


IPv6 Efforts Officially Started in 2006

IETF 6LoWPAN Working Group Charter, 2006 RFC 4944: Initial 6LoWPAN Standard, 2007

J. Hui and D. Culler. IP is Dead, Long Live IP for Wireless Sensor Networks.In Proceedings SenSys, Raleigh, NC, USA, 2008

RFC 6282: Header Compression Update, 2011 RFC 6550: RPL Routing, 2012 RFC 6775: Neighbor Discovery Update, 2012


IP Convergence and CoAP, MQTT, etc. in 2014

… are now pushing the Internet of Things


6LoWPAN Basics


Edge Networks

LoWPAN

Internet

RouterServer

Localserver

Border Router

PC

Backbone (LAN)


Low-power IP Stack

Layer ProtocolApplication CoAP / (HTTP / MQTT)

Transport UDP + DTLS (– TCP)

Network IPv6 + RPL / ND

Adaption 6LoWPAN

MAC CSMA (+ link-layer bursts)

Radio Duty Cycling IEEE 802.15.4e / ContikiMAC

Physical IEEE 802.15.4


IPv6 + UDP Header = 48 Bytes0 1 2 30 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+|Version| Traffic Class | Flow Label |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| Payload Length | Next Header | Hop Limit |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| |+ +| |+ Source Address +| |+ +| |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| |+ +| |+ Destination Address +| |+ +| |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| Source Port | Destination Port |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| Length | Checksum |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| UDP Payload ...+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

128 bits16 Bytes


… prefixes

IPv6 Addressing

LoWPAN

ISP

Router

Border Router Backbone (LAN)

2001:620:8::/48

2001:620:8:32D6::/64

2001:620:8:32C3::/64

EUI-64 = MAC addr.11:22FF:FF33:44552001:620:8:32D6:


Stateless Header Compression


Exact Number of Bytes Varies

Imag

e: J

. Sen

s. A

ctua

torN

etw

.201

3, 2

(2),

235-

287;

doi

:10.

3390

/jsan

2020

235

http://dx.doi.org/10.3390/jsan2020235


Stateful Compression with Context Identifiers

Imag

e: J

. Sen

s. A

ctua

torN

etw

.201

3, 2

(2),

235-

287;

doi

:10.

3390

/jsan

2020

235

http://dx.doi.org/10.3390/jsan2020235


6LoWPAN Fragmentation

Minimal MTU of IPv6: 1280 Bytes

127 B 127 B 127 B 127 B 127 B 127 B 127 B 127 B 127 B

802.15.4 Frames


Routing


LoWPAN

Route-over with RPL \“Ripple”\

Border Router DODAG Root

Host

Router

source routing


LoWPAN



Host

Router

storing modeMPL multicast


LoWPAN



Host

Router

multiple DODAGs


LoWPAN

Mesh-under with 6LoWPAN-ND

Border Router

Host

Host

Whiteboard

duplicate addressdetection (DAD)

short-addressgeneration

look-upsmobility


Radio Duty Cycling


Power Consumption

0

5

10

15

20

25

CPU(normal/LPM)

Radio(RX/TX)

Flash(R/W/idle)

Sensors(tmp./PIR/acc.)

LEDs

Cur

rent

con

sum

ptio

n (c

a.) [

mA]


ContikiMAC

A

D

A

D A

ACK frame

Data frame

Radio on

Sender

Receiver

Transmission detected

DD DD

Channel check


Link-layer Bursts

A

AD

Sender

Receiver

Transmission detected

DD DD

Channel check

A

AD

D A

AD

D A

AD

D

D

A ACK frame

Data frame

Radio on


Trading Energy for Latency

Number of hopsNumber of hops

Ener

gy[m

J]

Late

ncy

[s]

No duty cyclingContikiMAC

1 2 3 4

0

100

200

300

400

1 2 3 40

0.2

0.4

0.6

0.8

1.0


Current Efforts


State of the Art in Low-power IP

Scale 16.000 nodes in one multihop network (Cisco) RPL for smart metering

Reliability >99% package delivery ratio in LLNs Low-power Wireless Bus (constructive interference for flooding) Opportunistic RPL (combination with ContikiMAC) 6TISCH

Efficiency years of battery lifetime (through <1% RDC) ContikiMAC, A-MAC, … 802.15.4e


New 6LoWPAN bindings

Bluetooth Low Energy (BLE)

Z-Wave / ITU-T G.9959

DECT Ultra Low Energy (DECT ULE)

Generic Headers Compression

6lo Working Group

Mesh networkingfor Bluetooth 4.1


An Application Layer for the Internet of Things

Web scripting IoT devices

Constrained Application Protocol (CoAP)


Interoperable, scalable security

Public key cryptography

Elliptic curve cryptography

Hardware acceleration

DTLS Profiles (DICE)

Secure multicast?

Auth. in Constrained Environments (ACE)

Next Big Thing for Low-power IP

Questions?

Matthias Kovatsch https://github.com/mkovatsc/[email protected] http://people.inf.ethz.ch/mkovatsc/

https://github.com/mkovatsc/

mailto:[email protected]

http://people.inf.ethz.ch/mkovatsc/

Technology

Low-power IP: 6LoWPAN & Co