ZIGBEE

1. ZIGBEE Erkan Ünal CSE 401 SPECIAL TOPICS IN COMPUTER NETWORKS

2. OUTLINE • ZIGBEE AND APPLICATIONS • ZIGBEE PROTOCOL • ZIGBEE ALLIANCE • ZIGBEE APPLICATIONS • IEEE 802.15.4 PROTOCOL • PHYSICAL LAYER • MAC LAYER • ZIGBEE SPECIFICATION • NETWORK LAYER • SECURITY IN ZIGBEE • ZDO AND APPLICATION SUB-LAYER

3. SENSOR/CONTROL NETWORK REQUIREMENTS • Networks form by themselves, scale to large sizes and operate for years without manual intervention • Extremely long battery life (years on AA cell), • low infrastructure cost (low device & setup costs) • low complexity and small size • Low device data rate and QoS • Standardized protocols allow multiple vendors to interoperate

4. WHAT IS ZIGBEE PROTOCOL? • The IEEE 802.15.4 covers the physical layer and the MAC layer of low-rate WPAN. • The ZigBee is “an emerging standard that is based on the IEEE 802.15.4 and adds network construction (star networks, peer-to-peer/mesh networks, and cluster-tree networks), application services, and more”.

5. ZIGBEE ALLIANCE • Organized as an independent, neutral, nonprofit corporation in 2002 • Open and global • Anyone can join and participate • Membership is global • Activity includes • Specification creation • Certification and compliance programs • Branding, market development, and user education

6. ZIGBEE ALLIANCE • Is a growing community of companies • ~200 members vs. 35 Dec. 2002 (5+X Growth) • Includes major names in the Semiconductor, Software Developer, End Product Manufacturer, and Service Provider Industries including major Telecom Carriers • Has made its specification publicly available • ZigBee is open to all-ZigBee 2006 now available • 38,000+ downloads to date • Has over 30 compliant platforms • Many certified vendors make choosing ZigBee a safe choice • No dominating elements or companies.

7. WHY ZIGBEE? • Standards based • Low cost • Can be used globally • Reliable and self healing • Supports large number of nodes • Easy to deploy • Very long battery life • Secure

8. The IEEE 802 Wireless Space WWAN IEEE 802.22 IEEE 802.20 WMAN WiMax IEEE 802.16 Range WLAN WiFi 802.11 ZigBee 802.15.4 15.4c 802.15.3 802.15.3c Bluetooth 802.15.1 WPAN 0.01 0.1 1 10 100 1000 ZigBee standard uniquely fills a gap for low data rate applications Data Rate (Mbps)

9. ZIGBEE PROMOTERS

10. ZIGBEE APPLICATIONS security HVAC AMR lighting control accesscontrol TV VCR DVD/CD remote ZigBee Wireless Control that Simply Works PC & PERIPHERALS PERSONAL HEALTH CARE patient monitoring fitness monitoring TELECOM SERVICES asset mgt process control environmental energy mgt security HVAC lighting control access control irrigation m-commerce info services object interaction (Internet of Things)

11. Home Automation [HA] Defines set of devices used in home automation Light switches Thermostats Window shade Heating unit etc. SOME APPLICATION PROFILES

12. SOME APPLICATION PROFILES • Industrial Plant Monitoring • Consists of device definitions for sensors used in industrial control • Temperature • Pressure sensors • Infrared • etc.

13. MORE APPLICATION PROFILES • Multiple profiles at various stages of completion • Commercial Building Automation • Building control, management, and monitoring • Telecom Services/M-commerce • Automated Meter Reading • Addresses utility meter reading • Wireless Sensor Networks • Very low power unattended networks • Vendors may form new profile groups within ZigBee and/or propose private profiles for consideration • 400+ private profile IDs issued

14. In-Home Patient Monitoring graphic • Patients receive better care at reduced cost with more freedom and comfort • Patients can remain in their own home • Monitors vital statistics and sends via internet • Doctors can adjust medication levels • Allows monitoring of elderly family member • Sense movement or usage patterns in a home • Turns lights on when they get out of bed • Notify via mobile phone when anomalies occur • Wireless panic buttons for falls or other problems • Can also be used in hospital care • Patients are allowed greater movement • Reduced staff to patient ratio graphic

15. Wireless lighting control Dimmable intelligent ballasts Light switches/sensors anywhere Customizable lighting schemes Quantifiable energy savings Opportunities in residential, light commercial and commercial Extendable networks Lighting network can be integrated with and/or be used by other building control solutions Commercial Lighting Control

16. DEFINITION OF IEEE 802.15.4 STANDARD • IEEE Std 802.15.4 defines the physical layer (PHY) and medium access control (MAC) sublayer specifications for low-data-rate wireless connectivity with fixed, portable, and moving devices with no battery or very limited battery consumption requirements typically operating in the personal operating space (POS) of 10 m. It is foreseen that, depending on the application, a longer range at a lower data rate may be an acceptable tradeoff.

17. IEEE 802.15.4 DEVICE TYPES • The IEEE 802.15.4 standard (2003) defines the device types that can be used in a LR-WPAN which are Full Functional Device (FFD) and Reduced Functional Device (RFD). • The RFD can be used in simple applications in which they do not need to transmit large amounts of data and they have to communicate only with a specific FFD

18. IEEE 802.15.4 DEVICE TYPES • The FFD can work as a PAN coordinator, as a coordinator, or as a simple device. It can communicate with either another FFD or a RFD.

19. LR-WPAN TOPOLOGIES • In keeping with the application requirements, the LR-WPAN operates in a star or peer-to-peer topology. • The star topology the RFD communicates with a single controller, the PAN coordinator. • The PAN coordinator can perform the same function as the RFD, but it is also responsible for controlling the PAN; “it initiates, terminates, or routes communication around the network”

20. LR-WPAN TOPOLOGIES • Peer-to-peer topology supports ad-hoc mesh multi-hop networking. • Any device in the peer-to-peer topology can communicate with any other device within its communication range; however, this topology also has a PAN coordinator. • All the devices in a LR-WPAN have a unique 64-bit address. This or a short address, allocated by the PAN coordinator, can be used inside a PAN. • Each PAN has a unique identifier. The combination of the PAN identifier and the sort addresses allows communication across different PANs

21. LR-WPAN TOPOLOGIES Star and Peer-to-Peer topologies in LR-WPAN

22. PHYSICAL LAYER • The 802.15.4 standard specifies two different services that the Physical Layer(PHY) provides. • The PHY data service controls the radio, and thus, the transmission and reception of the PPDUs. • The management service performs Energy Detection in the channel, Clear Channel Assesment before sending the messages and provides LQI for the received packets.

23. IEEE 802.15.4 BANDS • 868/868.6 MHz for Europe • 902/928 MHz for North America • 2400/2483.5 MHz worldwide

24. PPDU PACKET FORMAT • The LSB is always transmitted and received first • The PPDU size can be up to 127 bytes

25. MAC LAYER • Interface between the SSCS and the PHY layer. • Similarto the PHY layer, the MAC layer supports two services. • The MAC data serviceis responsible for the transmission and reception of the MPDUs through thePHY data service.

26. MAC LAYER • The MAC management service, if the device is acoordinator, manages the network beacons. It is also responsible for PANassociation and disassociation, frame validation, and acknowledgmentproviding “a reliable link between two peer MAC entities.” • Uses the CSMA/CA for channel access and handles and maintains the GTSmechanism. • Supports device security.

27. MAC LAYER FRAME FORMATS • The IEEE 802.15.4 standard defines four different frame types: the beacon,data, acknowledgment, and MAC command frame. • All frame types are basedon the general MAC frame format. • The frame control field describesand specifies the above different frame types.

28. MAC LAYER FRAME FORMATS • Every MAC frame comprises aMHR, which consists of a frame control, sequence number, and theinformation field. It also contains the MAC payload. • Different frame typeshave different MAC payload fields.

29. GENERAL MAC LAYER FRAME FORMAT • Each frame includes a MFR, which contains a FCS. • Thedata in the MPDU follows the same order as the PPDU: the least significantbits are left in the frame and are transited first.

30. BEACON FRAME FORMAT • The beaconframe is transmitted periodically by the PAN coordinator. • It providesinformation about the network management through the super frame andGTS fields. • It also synchronizes thenetwork devices and indicates the proper communication period for them.

31. DATA FRAME FORMAT • Encapsulates data from the higher layers.

32. ACKNOWLEDGEMENT FRAME FORMAT • Does not have a payload. • When adevice receives a packet, it is not obliged toresponse with anacknowledgement packet

33. COMMAND FRAME FORMAT • Useful for communicationbetween the network devices. • The command identifier specifies actions likeassociation, disassociation, and data, GTS or beacon request.

34. SUPER FRAME • In the LR-WPAN, every PAN has its own coordinator. The PAN coordinatormanages the communication in the local area; it has two options, to use or notuse the super frame structure. • The super frameuses networkbeacons. • If the coordinator does not want to use a super frame structure, itsuspends the beacon transmission.

35. SUPER FRAME • The beacon is important fordevice association and disassociation. • If the coordinator wishes to maintainclose communication control in the PAN, and to support low-latency devicesit usually uses the super frame. • A super frame determines a specific time period, beacons bound it.

36. SUPER FRAME STRUCTURE

37. DATA TRANSFER TYPES • Three different types of datatransferexist. • Data transfer from a device to the PAN coordinator. • Data transfer from the PAN. • Peer-to-peer Data Transfer • The types differ if the coordinator uses or does notbeacons

38. DATA TRANSFER FROM A DEVICE TO THE PAN COORDINATOR

39. DATA TRANSFER FROM THE PAN COORDINATOR

40. PEER-TO PEER DATA TRANSFER • The devices arefree to communicate with any other device within their communication range. • In a peer-to-peer PAN the devices can “either receive constantly orsynchronize with each other.” • If they are receiving constantly, to transmitdata they use un-slotted CSMA-CA. In the second case, synchronization mustbe achieved first.

41. SECURITY IN IEEE 802.15.4 • Provides a securitybaseline, including “the ability to maintain an ACL and use symmetriccryptography” for data encryption. • The algorithm that is used for encryptionis the AES. • The higher level layers decide when security is need. • Theupper layers are in general responsible for device authentication and keymanagement.

42. ZIGBEE STANDARD • ZigBee, a new standard which became publicly available in June 2005, isbased on the IEEE 802.15.4 standard. • It expands the IEEE 802.15.4 by addingthe framework for the network construction, security and application layer services.

43. ZIGBEE STACK

44. NETWORK LAYER • The ZigBee standard works on topof the IEEE 802.15.4 addressing schema by using the standard 64-bit and theshort 16-bit addressing. • Network layerresponsibilities: • Establishment of a new network. • New device configuration, addressing assignment, networksynchronization • Frames security • Message routing.

45. DEVICE TYPES • Uses notion of “logical devices.” • “ZigBee Coordinator” is the first typeof logical devices. • It is responsible for initializing, maintaining, and managingthe network. • Under the coordinator in the network hierarchy is the “ZigBeerouter,” • Responsible for controlling the message routing between thenodes. • “ZigBee End Device” acts as the end point of the network structure.

46. ZIGBEE NETWORK TOPOLOGIES

47. SECURITY IN ZIGBEE • Security services provided byZigBee: “key establishment, key transport, frame protection, and devicemanagement.” • The security mechanism covers the network and theapplication layer. • The notion of end-to-end security issupported; the source and destination devices have access and use the sameshare key. • In the MAC layer the 802.15.4 AES mechanism provides the proper security.

48. SECURITY IN ZIGBEE • The mechanism protects “the confidentiality, integrity, and authenticity of theMAC frames” • An auxiliary header field in front of the MACpayload indicates if the frame is encrypted or not. • The MAC frames’ integrityis supported by calculating and using a MIC at the end of the MAC payload. • Nonce is used to provide MAC confidentiality andauthenticity.

49. SECURITY IN ZIGBEE • For differentsecurity aspects the MAC layer uses different mode of the AES: • For theencryption it uses the AES in Counter (CTR) mode. • For the integrity, theCBC-MAC. • Combination (CCM) of the above two modes.

50. SECURE MAC FRAME