6lowpan 110828234426-phpapp01
Transcript of 6lowpan 110828234426-phpapp01
6LoWPAN(IPv6 over Low power Wireless
Personal Area Networks)
Introduction • IP based devices
• web services• security• management• frame size
• issues• power & duty cycle• multi cast• topology• bandwidth• reliability
Internet of things
Related TechnologiesRFC 4944 ISA 100 IPSO
Applications
Home building automationHealth care Industry Automation & LogisticsVehicular AutomationEnvironmental monitoring and many more
Architecture
Protocol stack
• UDP is preferred
Link layersCompatibility with existing technologies like
802.15.4, Sub-GHz Radio and Power- line communications.
Adaptation for IP Addressing of nodes (Locally & Globally)
AddressingExtended Unique identifier(EUI-64) -- like
ZigbeeConfigurable short addressing(8-16 bits)Similar like IPv6 64 bits IID is used---
generally called Stateless Address Auto configuration (SAA)
Forwarding and Routing
1. IP Routing Model
2. LoWPAN Routing(L3 , Route over)
Forwarding and Routing (contd..)
3(a). DLL mesh forwarding (L2, Mesh Under)
3(b). LoWPAN adaptation (L2, Mesh Under)
Header Compression Headers of IP is compressed(IPv6 headers occupy more
space) Router decompresses the header and transmits over
different link
MTU is not sufficient Need to achieve flow control Must be used when needed The throughput of network reduces
Fragmentation and Reassembly
Data Packet of 802.15.4802.15.4 IPv6 header Payload
802.15.4 Mesh Addr Frag IPv6 header Payload
802.15.4 Fragmentation IPv6 header Payload
128 bytes
Payload
decreases
Fragmentation Header
Mesh Header
IP Header format (HC)
For IP , HC1 is used HC2 bit indicates further transport protocols UDP, TCP, ICMPv6
IPv6 Header
UDP
RFC4944’s HC TF,FL into 2 bits Version, Payload Length,
Link Local Prefix UDP ports (61616-61631)
Uni Cast
Multi Cast
Global
Improved HC (IPHC) TF,FL are
individually compressed
Hop limit compression
Removes prefixes for IPv6 addresses
Supports Multicast for ND, SLAAC
4 bit index represents 16 contexts (if CID is set)
U
M
G
Networking Issues
Establishing a network (Commissioning)◦ new node joining◦ Network re-organizing
Uses ◦ Service Set ID (WLAN)◦ Security (Wireless Protected Access)
Prefix match -- Home network Neighbor Discovery
◦ DHCPv6 (Stateless Address Auto configuration)◦ Registration◦ Reg. collision◦ Multi-hop registration◦ Various operations (node, router, edge router)
Bootstrapping
Networking Issues (contd..) Objectives
◦ Confidentiality◦ Integrity◦ Availability
Layer2 mechanisms◦ As 802.15.4 implements AES(CCM, RFC 3610)◦ 13 byte key based on 8 byte MAC Id◦ 2^22= 7 weeks of key repetition
Layer3 mechanisms (Internet Key Exchange [RFC 2409])◦ Doesn’t suit for LoWPANs
Key Management (Enhanced L3)◦ Username & Password◦ Long, Short, Group, Pair wise keys
Security
Other Aspects Mobility
◦ Roaming (macro)◦ Handover (micro)
Causes◦ Physical movement◦ Radio channel◦ Network performance◦ Sleep schedules◦ Node failure
Node & Network controlled (Wi-Fi, cellular systems)
Solutions for Mobility◦ Commissioning◦ Bootstrapping◦ Security◦ Updating DNS◦ Notifying upper layers
So far nodes are considered stationary
Other Aspects (contd..)MIPv6 Proxy Home Agent
Other Aspects (contd..)Proxy MIPv6 NEMO (NEtwork MObility)
Application protocols General IPv6
◦ HTTP, FTP, SIP, SNMP, RTP, SLP Need modifications SOAP, REST (Simple Object Access Protocol,
REpresenational State Transfer) Need Port Address
Application protocols (contd..)
NetworkingHost IssuesCompressionSecurity
Application protocols (contd..) Protocol paradigms
◦ End to End◦ Real Time Streaming / Session◦ Pub/ Sub
Common Protocols◦ Web service protocols◦ MQTT (MQTT-S)◦ ZIGBEE Compact Application Protocol◦ Service Discovery
SLP, UPnP, DPWS◦ Industry Specific (BACnet, oBIX, ANSI c12.19)
ZCAP, MQTT has own discovery features
Implementing 6lowpan
Single Chip Two Chip
Implementing 6lowpan (contd..) Protocol Stacks
◦ ContikiOS & uIPv6◦ TinyOS & BLIP◦ Sensinode NanoStack◦ Jennic 6LoWPAN◦ Nivis ISA100 (Industrial Standard)
Implementing 6lowpan (contd..) ContikiOS
◦ C◦ MSP430, AVR, HC12,
Z60, etc..◦ 2kB RAM, 40kB ROM◦ LoWPAN Support◦ Multitasking◦ Event driven kernel◦ uIP stack◦ Thread based◦ COOJA Simulator◦ TMote
TinyOS◦ nesC◦ MSP430, AVR◦ 0.4kB RAM◦ LoWPAN Support◦ BLIP◦ TOS Simulator◦ FIFO◦ OS merges with
Program◦ TelosB, IMote etc..
Implementing 6lowpan (contd..)
Application development
Hardware Interaction layer
Hardware Implementation Layer
nesC
TinyOS
H/W Platform
Contiki OSTinyOS