IEEE 1451'5 Wireless interface option for 1451

1
IEEE 1451.5 Wireless interface option for1451

• Fall 2005
• ProfDr.Schmalzel
• Smart Sensors
• RaviKiran Kandalam

2
Contents

• What is 1451.5
• Overview of the 1451 Reference
• Key Elements of Sensor Standard
• Envisioned wireless structure
• 1451.5 Use of Core 1451.0 TEDS
• 802.11
• 802.11 standards
• 802.11a,b,d,e,f,g,h,i
• 802.11 architecture
• Ad-hoc network and ESS
• Layered frame work in NCAP and WTIM
• 802.11 PHY TEDS
• Bluetooth (802.15.1)
• What is Bluetooth
• Layered frame work in NCAP and TIM
• Bluetooth Features for IEEE1451.5
• Bluetooth Architecture
• Network Topology and its functional Overview
• Bluetooth Security

3
What is IEEE1451.5

• IEEE P1451.5 defines a transducer-to-NCAP
  interface and TEDS for wireless transducers.
• Wireless communication protocol standards
• 802.11 (Wi-Fi)
• 802.15.1 (Bluetooth)
• 802.15.4 (ZigBee)
• are being considered as some of the physical
  interfaces for IEEE P1451.5.
• One should be able to get the same sensor data
  from the wireless sensor implementing any of
  these three wireless protocols.

4
Overview of the 1451 Reference
5
Key Elements of Sensor Standard

• TEDS
• Synchronization of Data Sampling
• Unique Identification
• Accessibility to Networks (e.g. Internet)
• Plug-and-Play Sensor Connections

6
Envisioned Wireless Structure
7
1451.5 Use of Core 1451.0 TEDS

• Meta TEDS
• Describes the relation between the transducer
  channels that exists within the TIM.
• Stores the Time related parameters (worst-case
  timing parameters to check if TIM is responding
  or not).
• Transducer Channel TEDS
• Provides detailed information about a specific
  transducer (what physical parameter is being
  measured or controlled, the range over which the
  Transducer Channel operates, )
• Users Transducer Name TEDS
• This TEDS is intended to provide a place for the
  user of the transducer to store the name by which
  the system will know the transducer.
• Contents of the TEDS are user defined
• 1451.5-Specific PHY TEDS
• 802.11 PHY TEDS
• Bluetooth PHY TEDS
• ZigBee PHY TEDS

8
IEEE 802.11

• 802.11 standard specifies wireless for fixed
  portable and moving clients in a limited
  geographic area.
• In 802 LAN standards
• 802.3 ----- Ethernet
• 802.5 ----- Token ring
• Similarly 802.11 data rate of at least 1 Mbps
  and defines only the PHY and MAC layers.
• 802.11 MAC layer performs fragmentation, error
  recovery, mobility management, power conservation
  etc..

9
802.11 standards.

• Specifies the lowest 2 layers of OSI- MAC and PHY
• It is supplemented by a suite of extensions such
  as a, b, d, e, f, g, h, and i.
• Each extension has different physical layer,
  different wireless data rate but they all are
  based on same MAC protocol.
• 3 major extensions, a -- 5GHz, b 2.4GHz,
  and g works at the same frequency as a but is
  backward compatible with b extension.

10
802.11a

• Offers higher data rate at 5 GHz band, almost 5
  times higher than 802.11b.
• Advantages
• Has greater scalability (more channels are
  available, 12 vs 3 non overlapping radio channels
  for US operations)
• Better interference immunity
• Significantly higher speed

11

• Supports 4 indoor and 8 outdoor channels, with
  higher transmit power available for outdoor
  channels (more access points can be packed into
  same area, more users , higher data rate)
• Disadvantages
• 5 GHz signals have more trouble traveling thru
  walls, floors, furniture and other obstructions
• This system cannot be used in western European
  countries since 5GHz is reserved for another
  wireless LAN standard HiperLAN2.

12
802.11b

• Supports a max wireless data rate of 11 Mbps.
• Supports a max of 3 non-overlapping channels.
• Supports fallback rates of 5.5, 2Mbps, and 1Mbps.
• Drawbacks
• It suffers from interference in congested 2.4GHz
  band (ex High power microwave ovens)
• Has lower data rate than extension a and g.

13
802.11d

• Deals with regulatory issues
• Defines how access points exchange information on
  permissible radio channels
• And associated power levels at user end
• 802.11e
• Outlines how QoS and multimedia applications can
  be accommodated by enhancing 802.11 std

14
802.11f

• Defines inter-access point protocol (IAPP) that
  facilitates roaming across access points from
  multiple vendors
• Also deals with the wireless security issues.
• 802.11g
• It is a ratified standard of extension a
• Operates at 5GHz and provides data rate of 54Mbps
• Provides backward compatibility with extension b

15
802.11h

• Major improvements include
• channel energy measurement and reporting
• channel coverage in regulatory domains
• Dynamic channel selection (DCS)
• Transmit power control (TPC)
• 802.11i
• This task group was formed to look into improving
  the effectiveness of WEP and removing some
  security flaws

16
802.11 Architecture
17
802.11 Topologies

• When two or more stations come together to
  communicate with each other, they form a BSS

• A BSS that stands alone and is not connected to a
  base is called an IBSS or is referred to as an
  Ad-Hoc Network.

• Two or more BSS's are interconnected using a
  Distribution System or DS

• data moves between the BSS and the DS with the
  help of these access points

18
Layered Framework in NCAP WTIM
802.11,a/b/g at PHY (physical
layer) 802.11,i/e at MAC (data link layer) IP
version 4 or version 6 (network layer) TCP or
UDP (transport layer) IEEE p1451.0/X
Communications API (communication
management) Application to LAN backbone (NCAP)
or TMAPI (WTIM)
19
802.11 PHY TEDS

• --802.11 MAC Attributes
• --DEFINED AS "The MAC object class provides the
  necessary support
• --for the access control, generation, and
  verification of frame check
• --sequences, and proper delivery of valid data to
  upper layers."
• dot11mac OBJECT IDENTIFIER ieee802dot11 2
• --MAC GROUPS
• --dot11OperationTable dot11mac 1
• --dot11CountersTable dot11mac 2
• --dot11GroupAddressesTable dot11mac 3
• --802.11 PHY Attributes
• --DEFINED AS "The PHY object class provides the
  necessary support
• --for required PHY operational information that
  may vary from PHY
• --to PHY and from STA to STA to be communicated
  to upper layers."
• dot11phy OBJECT IDENTIFIER ieee802dot11 4
• --phyGROUPS
• --dot11PhyOperationTable dot11phy 1
• --dot11PhyAntennaTable dot11phy 2

20
What is Bluetooth

• Enable short-range unconscious radio
  communications personal area networks
• Key enablers
• Low cost
• Robust and reliable
• Low user maintenance
• Easy to enable, easy to use
• Upwards compatibility

21
Layered frame work in NCAP and TIM
22
Bluetooth Features for IEEE1451.5

• Bluetooth has many features that make it a
  suitable for wireless technology for IEEE1451.5
• Device Discovery
• Bluetooth Inquiry mode allows devices to be
  discovered
• The Class of Device identified during inquiry
  allows filtering for device types
• Bluetooth Service Discovery Profile (SDP) allows
  for browsing for features and services
• Connections
• Bluetooth allows piconets with point to
  multipoint connections of up to 7 slaves to one
  master
• Synchronous (SCO) channels for data streaming
• Data rates up to 723 Kbytes using asynchronous
  (ACL) channels
• Low power modes to allow battery powered devices
  with projected life in years

23
Bluetooth Architecture

• Two types of specifications
• Core spec
• Profile spec
• Discuss how technology works
• Deals with how to build interoperating devices
  using the core technologies

24
RF

• Bluetooth air interface is based on nominal
  antenna power of 0dBm (1mW) with extensions
  operating at up to 20dBm world wide.
• Radio uses FHSS (79 hops)
• Nominal link range 10 cm to 100 cm
• Can be increased to beyond 100 cm increasing
  transmit power.

25
Baseband

• The radio operates in a FH manner (2.4 GHz 79
  1MHz channels)
• A piconet is formed when one Bluetooth radio is
  connected to other.
• Both hop together thru 79 channels.
• Bluetooth frame consists of a transmit packet
  followed by a receive packet.
• Each packet can be composed of multiple slots (1,
  3, or 5) of 625 us.
• Multi-slot frames allow higher data rates because
  of the elimination of the turn-around time
  between packets

26
Bluetooth Usage Model

• Usage model is based on connecting devices
  together.
• 3 categories
• voice/data access points,
• peripheral interconnects, and
• Personal Area Networking (PAN).

27
Voice data access points

• computing device communication device via
  secure wireless link
• Ex a mobile computer equipped with Bluetooth
  could link to a mobile phone to access emails and
  stuff.

28
Peripheral Interconnects

• Connecting other devices together is PI
• Ex connecting keyboard, mouse, joystick together
  over a wireless link.
• In this case access point is the computer and all
  other devices use that access point

29
Personal Area Networking (PAN)

• It is an ad-hoc formation and break down of
  personal networks.
• Ex meeting someone in the airport and quickly
  and securely transferring documents by
  establishing a private piconet

30
Network Topology

• A piconet is formed when at least
• 2 devices are connected in an ad-hoc
  fashion using Bluetooth tech.
• A piconet supports up to 8 devices.
• When a Piconet is formed one device
• acts as master and the rest acts as slaves
• It is also sometimes called as PAN
• Each Bluetooth has a unique global ID that is
  used to create the hopping pattern.
• Master shares its GID and all the other radios
  that share this ID become slaves

31
Functional Overview
32
Bluetooth security

• Bluetooth radio system provides Authentication,
  Encryption, and Key Management.
• Provides a Personal Identification Number (PIN)
  translated into a 128-bit link key that can be
  authenticated in a one or two-way direction.
• Bluetooth security architecture relies on PIN
  codes for establishing trusted relationships
  between devices.

33
ZigBee Architecture
Applications

• Network Routing
• Address translation
• Packet Segmentation
• Profiles

ZigBee

• Channel acquisition
• NIC address
• Error Correction

IEEE 802.15.4 MAC

• Packet generation
• Packet reception
• Data transparency
• Power Management

IEEE 802.15.4
IEEE 802.15.4
2400 MHz
868/915 MHz
PHY
PHY
34
802.15.4 General Characteristics

• Data rates of 250 kb/s, 40 kb/s and 20 kb/s.
• Star or Peer-to-Peer operation.
• Support for low latency devices.
• Fully handshake protocol for transfer
  reliability.
• Low power consumption.
• Frequency Bands of Operation
• 16 channels in the 2.4GHz ISM band
• 10 channels in the 915MHz ISM band
• 1 channel in the European 868MHz band.

35
ZigBee application space

• 802.15.4 application space

• Home Networking
• Automotive Networks
• Industrial Networks
• Interactive Toys
• Remote Metering

36
Device types
37
IEEE 802.15.4 MAC Overview
Star Topology
ZigBee Coordinator or
Full function device
PAN coordinator
Reduced function device
reduced function device
38
IEEE 802.15.4 MAC Overview
Peer-Peer Topology
Mesh topology
Point to point
networks enable high levels of reliability and
scalability by providing more than one path
through the network
39
IEEE 802.15.4 MAC Overview
Combined or Cluster tree Topology
Clustered stars - for example, cluster nodes
exist between rooms of a hotel and each room has
a star network for control.
networks utilize a hybrid star/mesh topology that
combines the benefits of both for high levels of
reliability and support for battery-powered
nodes.
40
Typical ZigBee-Enabled Device Design
Typical design consist of RF IC and 8-bit
microprocessor with peripherals connected to an
application sensor or actuators
41
How does ZigBee compare to other wireless
standards?
42
ZigBee Envisioned PHY TEDS

• 802.15.4-ZigBee MAC attributes
• ZBmacAckWaitDuration
• ZBmacAssociationPermit
• ZBmacBattLifeExt
• ZBmacBeaconOrder
• ZBmacBeaconTxTime
• ZBmacGTSPermit
• ZBmacMaxCSMABackoffs
• ZBmacMinBE
• ZBmacRxOnWhenIdle
• ZBmacSuperframeOrder
• 802.15.4-ZigBee PHY attributes
• ZBphyChannelsSupported
• ZBphyTransmitPower
• ZBphyCCAMode

43
References

• www.ieee802.org/11
• www.zigbee.org
• Teik-kheong Tan and Benny Bing, world wide
  WI-FI, a John Wiley and sons inc.
  publication,2003
• http// www.atmel.com/products/zigbee/
• www.palowireless.com/zigbee
• http//en.wikipedia.org/wiki/ZigBee
• http//www.tutorial-reports.com/wireless/wlanwifi/
  index.php
• Ryon Coleman, Status of P1451.5 802.11
  Sub-Specification, rcoleman_at_3eti.com, June 7,
  2004
• James Kardach, Principle Engineer Bluetooth SIG
  Program Manager Intel Corporation, Bluetooth
  Architecture Overview, 1998
• Peter Flittner, CSR (Bluetooth Subgroup Chair)
  Thurston Brooks, 3eTI, IEEE P1451.5 Wireless
  Sensor Interface Working Group Bluetooth Subgroup
  Proposal,

44
homework

• Explain in brief the TEDS example given in the
  slides 19 and 42(what are the attributes listed
  in and what do they refer to)