Transcript New Echelon Products 2005 - ISO/IEC JTC1 SC25 WG1 Home …

ANSI/CEA709 (EN14908)
Standards
August 2006
Vijay Dhingra
04H1122
Background
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Data networks interconnect computers, servers, and printers
Control networks connect sensors, actuators, displays, and other
machines to each other, to remote monitoring sites, and to the Internet
– All control networks perform a common set of functions: they sense,
process, actuate, and communicate
Internet
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Control Network Technology Requirements
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Robust, reliable communications
– Peer-to-peer protocol supports multiple media, efficient
addressing and authentication
– No single point of failure in the control system
– Predictable, autonomous applications regardless of
network traffic
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Open standards based and Interoperable products
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Large Ecosystem of cost effective solution
– Best of breed products in commercial and home market
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Confidence and leverage in a future proof environment
Multiple Media Support
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Control applications require flexibility in selecting
communication medium
– Protocol and routing technology that allows multiple
media (Mixed as needed within system):
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Power line
Twisted pair
Fiber optic
RF
Coaxial cable
Infrared
IP
Interface with other home networking
standards/protocols
– With simple application layer bridging
LONWORKS Control Networks
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Flat Peer-Peer Network Architecture
– Eliminate complex cabling
– Lower installation and maintenance costs
– Eliminate proprietary & closed gateways, and central
controllers
– Simplify HMI development
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Open
– Choose interoperable components from multiple vendors
ANSI/CEA-709.1-B
Control Networking Protocol
ANSI/CEA-709.1-B Protocol
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An open standard protocol for control applications
– Control applications have different requirements than data
applications
– TCP/IP is an example of a data networking protocol
– Reference document available from Global Engineering
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Protocol implementations are available from multiple vendors
– Protocol can be ported to any processor
– Echelon’s implementation is called the LonTalk® protocol
– Echelon’s Neuron® firmware includes the LonTalk protocol
– Echelon development systems include a royalty-free unlimited
license to use the Neuron firmware implementation
ANSI/CEA-709.1 Protocol Layers
Application
Presentation
Session
Transport
Network
Data Link
Physical
Physical Media
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ANSI/CEA-709.1 is layered
– As recommended by the International Standards
Organization Open Systems Interconnect (ISO OSI)
reference model
– OSI layers ensure that the required services are provided
without unexpected interactions between the services
– Device manufacturers only need to change the application
ANSI/CEA-709.1 Protocol Layers
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OSI Layer
Purpose
Services Provided
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Application
Application Compatibility
Network Configuration; Network Diagnostics; File Transfer;
Application Configuration, Specification, Diagnostics,
& Management; Alarming; Data Logging; Scheduling;
Time & Date Management
6
Presentation Data Interpretation
5
Session
Control
Request-Response; Authentication
4
Transport
End-to-End Reliability
Acknowledged & Unacknowledged Message Delivery;
Duplicate Detection
3
Network
Message Delivery
Unicast & Multicast Addressing; Routers
2
Link
Media Access and Framing
Framing; Data Encoding; CRC Error Checking;
Predictive CSMA; Collision Avoidance;
Priority & Collision Detection
1
Physical
Electrical Interconnect
Media-Specific Interfaces and Modulation Schemes
(twisted pair, power line, radio frequency, coaxial cable,
infrared, fiber optic)
Network Variables; Application Messages;
Foreign Frame Transmission; Standard Types
A Typical ANSI/CEA-709.1 Packet
Layer 2
Header
Layer 3
Address Information
Layer 4
Service Type
Layer 5/ 6
Header
DATA
Layer 2
CRC
2 Bytes
Network
Variable
Selector
Service Type ID
Transaction Num
Unsigned
Long
2 Bytes
2 Bytes
1 Byte
Addr Format, Domain Length
1 Byte
Source Addr (Subnet/Node)
2 Bytes
Dest Addr (Group)
1 Byte
Domain ID (Zero Len Domain)
Backlog
Priority
Alt Path
0 Bytes
1 Byte
12 Bytes
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Layer 1—Physical Layer
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Electrical interconnect
– Transmission of raw bits over a communication channel
Physical Layer—Common Channel
Types
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Optimize cost and performance for a broad range of control applications
Name
Media
Bit Rate
Definition
Standard
DC-1250
Direct-Connect Twisted Pair
1.25Mbps
Neuron Chip Data Book
No
FO-20L
Fiber Optic
1.25Mbps
ANSI/CEA-709.4
Yes
FO-20S
Fiber Optic
1.25Mbps
ANSI/CEA-709.4
Yes
IP-852
ANSI/CEA-852 IP Tunneling
N/A
ANSI/CEA-852
Yes
PL-20A
CENELEC A-band Power
Line
2613bps
LONMARK Interoperability
Guidelines
Yes
PL-20C
CENELEC C-band Power
Line w/access
protocol
156.3k/3987bps
ANSI/CEA-709.2
Yes
PL-20N
CENELEC C-band Power
Line w/o access
protocol
156.3k/3987bps
ANSI/CEA-709.2
Yes
TP/FT-10
Free Topology Twisted Pair
78.13kbps
ANSI/CEA-709.3
Yes
TP/RS485-39
RS-485 Twisted Pair
39.06kbps
EIA/TIA-232-E
Yes
TP/XF-1250
Transformer-Isolated
Twisted Pair
1.25Mbps
LONMARK Interoperability
Guidelines
Yes
Typical Channel Capacities
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TP/FT-10 Channel
– Peak: ~225 packets/sec
– Sustained: ~180 packets/sec
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TP/XF-1250 Channel
– Peak: ~720 packets/sec
– Sustained: ~576 packets/sec
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PL-20x Channels
– PL-20N ~20 packets/sec
– PL-20C ~18 packets/sec
– PL-20A ~11packets/sec
IP-852 Channels
– ~10,000 packets/sec
– Supports aggregation
PL-20x
TP/FT-10
TP/XF-1250
IP-852
Physical Layer—TP/FT-10 Channel
Singly-Terminated Bus Topology
Star Topology
Doubly-Terminated Bus Topology
Mixed Topology
Loop Topology
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= Ter mination
Defined by ANSI/CEA-709.3-A Free-Topology Twisted Pair Channel Specification
Media is free topology twisted pair with optional link power
– Supports commonly available unshielded and shielded 0.50mm (24AWG) to 1.3mm
(16AWG) twisted pair wires
– Polarity insensitive wiring
– Reduces installation and maintenance costs
Up to 64 devices on a single network segment
– Or 128 devices along with a link power source
Available in cost-effective device-on-a-chip
– With all-in-one transceiver, application processor, and memory
Physical Layer—PL-20 Channel
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Advanced technology for reliable communication
– Dual carrier frequency operation
– Digital signal processing
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Worldwide operation
– Meets FCC, Industry Canada, Japan MPT, and
European CENELEC EN50065-1 regulations
regulations
– ANSI/CEA-709.2 compliant
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European utility support
– Dual frequency DSP performance in the A-Band
for AMR/DSM applications
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Available in cost-effective device-on-a-chip
– Transceiver, application processor, memory
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Proven technology
– Millions of devices installed worldwide
C-Band
115kHz 132kHz
A-Band
75kHz 86kHz
Layer 2—Link Layer
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Media access and framing
– Ensures efficient use of a single communications channel
– Raw bits of the physical layer are broken up into data
frames
– Link layer defines when a device can transmit a data frame
– Also defines how destination devices receive the data
frames and detect transmission errors
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Features
– CRC error checking
– Media access—predictive p-persistent CSMA
– Priority
– Collision avoidance
Link Layer—Media Access
Busy Channel
Packet Cycle
Predictive p-persistent CSMA
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Channel access is always
randomized over time slots
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Number of time slots are varied
based on collision avoidance
algorithm
– 16 to 1008 slots
Packet
Packet
Non-priority
Slots
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Link Layer—Media Access Priority
Busy Channel Packet Cycle
Packet
1 2 3 ... n
Packet
Priority Slots Non-priority Slots
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Configurable priority messages
– Reserved time slot
– Reduces overall channel bandwidth
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Priority slot number is assigned at installation time
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No collisions possible during priority portion of packet
cycle following preceding packet
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Highest priority message has predictable response time
Link Layer—Media Access Benefits
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Linear response time over 99% of channel bandwidth
– Critical for open media such as power line
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Remove and attach devices without halting communications
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Predictable performance for high-priority messages
Link Layer—709.1 MAC vs. Ethernet
from: Computer Networks, Andrew S. Tanenbaum, Fourth Edition, 2003.
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Layer 3—Network Layer
1
SUBNET 1
SUBNET 2
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Physical address
– 48-bit Neuron ID—used for initial
configuration
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Logical addresses
– Domain Identifies subsystem on
open media or
large system
– Subnet Subset of a domain typically
associated with a channel
– Node
Identifies device within
subnet
– Group
Additional device identifiers
independent of subnet
SUBNET 3 127
1
GROUP 1
1
SUBNET 4
SUBNET 255
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DOMAIN (32,385 Devices)
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Message delivery
– How data frames are routed from a
source device to one or more
destination devices
127
1
1
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Network Layer—Addressing Modes
Address Mode
Domain-wide
Broadcast
Address Format
Destination
Domain (Subnet = 0)
All devices in
the domain
3
All devices in
the subnet
3
Subnet-wide Broadcast Domain, Subnet
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Address Size
(bytes)
Unicast
Domain, Subnet,
Node
Specific device
within a subnet
4
Multicast
Domain, Group
All devices in
the group
3
Neuron ID
Domain, Neuron-ID
Specific device
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Optimize bandwidth with multiple addressing modes
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Application communications only requires 3- or 4-byte network addresses
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Send messages to many devices using only a single 3-byte network
address
Network Layer—Capacity
Room to grow from a few devices to millions
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18,446,744,073,726,329,086 domains
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255 subnets per domain
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127 devices per subnet
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32,385 devices per domain
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256 groups per domain
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64 devices per acknowledged group
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32,385 devices per unacknowledged group
Network Layer—Routers
Domain
Subnet 1
Subnet 1
Subnet 2
...
Channel
Router
Repeater
Group 1
Router
Subnet 5
Subnet 3
Group 1
Router
Group 2
Repeater
Subnet 4
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Extend channel segments
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Improve reliability
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Increase overall bandwidth
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Simplify network configuration
– Routers are transparent to devices and applications
Layer 4—Transport Layer
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End-to-end reliability—allows reliable delivery of message packets
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Three message delivery services
– Acknowledged
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Sending device requires acknowledgment from all
receiving devices
All acknowledgments are end-to-end
Automatic retries if acknowledgement not received
– Repeated
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Configurable number of messages per transaction
Conserves bandwidth with large groups
Better response time
Three repeats provides > 99.999% probability of delivery
– Unacknowledged
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S
R
Acknowledged - Unicast
S
R
R
RR
Acknowledged - Multicast
S
R
RepeatedUnicast or Multicast
S
R
One message per transaction
Unacknowledged Unicast or Multicast
Conserves network bandwidth and provides highest performance
Duplicate detection prevents repeated messages to the
application
Layer 5—Session Layer
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S
R
S
RR
R
R
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Adds control to the data exchanged by
the lower layers
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Request/response service
– Used for device management, fetching
values, and requesting other remote
actions
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Authentication
– Verifies identity of message sender…
Session Layer—Authentication
Sender
Authenticated Message
Receiver
64 bit Random Challenge
Key used to
transform
challenge
Key used to compare
response to value
transformed locally.
Challenge Response
Acknowledgment
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Verifies identity of message sender
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Uses a 48-bit secret key known by each device
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Sender must provide correct reply to 64-bit random
challenge from the receiver
Layer 6—Presentation Layer
Room Temp
Temp
Set Point
Temp Sensor
(Made in USA)
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Boiler System
(Made in Europe)
Set Point
Setpoint Display
(Made in Korea)
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Data exchanged using network variables
– Propagation automatically handled by Neuron firmware
– Provides fastest and most compact code
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Devices from different manufacturers can exchange data with a
common interpretation
Presentation Layer—Connections
Feedback
Room Occupied
Motion
Brightness
Motion Detector
Lamp
0% - 100%
Key Code
Control Knob
Intruder
Alarm
Arm / Disarm
Key Pad
Alarm Bell
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Sensors “publish” information, and actuators “subscribe” to information
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Devices are logically connected
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Connections do not affect device applications
Presentation Layer—Standard Types
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Standard network variable types
– Over 170 standard types defined at types.LONMARK.org
– XML definitions available for easy input/translation/interpretation by other
systems
Presentation Layer—Standard
Formatting
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Ensures consistent data presentation in tools and HMIs
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Example
– A SNVT_temp_p value of 2940 is displayed as follows:
29.4 degrees C
84.9 degrees F
52.9 degrees F
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Layer 7—Application Layer
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Defines standard network services that use data exchanged by
the lower layers
– Network configuration and diagnostics
– File transfer
– Application configuration, diagnostics, management, and
specification
– Standard profiles
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Alarming
Data logging
Scheduling
More than 60 others
Application Layer—Application Configuration
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Configuration properties characterize the behavior of a device in the system
– Types define data encoding, scaling, units, default value, range, and behavior
– Standard configuration property types defined at types.LONMARK.org
– XML definitions available for easy input/translation/interpretation by other
systems
Application Layer—Application Specification
Node Object
Mandatory Network Variables
nv1
nviRequest
SNVT_obj_request
nv2
nvoStatus
SNVT_obj_status
Optional Network Variables
nv3
nviTimeSet
SNVT_time_stamp
nv10 nvoAlarm2
SNVT_alarm_2
nv4
nvoAlarm
SNVT_alarm
nv9
nviDateEvent
SNVT_date_event
nv11 nvoDateResync
SNVT_switch
nv5
nviFileReq
SNVT_file_req
nv6
nvoFileStat
SNVT_file_status
nv7
nviFilePos
SNVT_file_pos
nv8
nvoFileDirectory
SNVT_address
nv12 nviLogReq
SNVT_log_req
nv13 nvoLogStat
SNVT_log_status
Configuration Properties
Mandatory
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Optional
Device Major Version
Device Minor Version
Functional Block Major Version
Functional Block Minor Version
Location
Maximum Status Send Time
Minimum Send Time (Send Throttle)
Network Configuration Source
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Functional block
– Portion of a device’s application
that performs a task
– Receives configuration and
operational data inputs
– Processes the data
– Sends operational data outputs
Application Layer—Standard Profiles
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