ANSI/CEA709 (EN14908) Standards August 2006 Vijay Dhingra 04H1122

Background 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

Control Network Technology Requirements 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 Open standards based and Interoperable products Large Ecosystem of cost effective solution Best of breed products in commercial and home market Confidence and leverage in a future proof environment

Multiple Media Support Control applications require flexibility in selecting communication medium Protocol and routing technology that allows multiple media (Mixed as needed within system): 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 Flat Peer-Peer Network Architecture Eliminate complex cabling Lower installation and maintenance costs Eliminate proprietary & closed gateways, and central controllers Simplify HMI development Open Choose interoperable components from multiple vendors Control networks are more common than you think. For example, your car may have several control networks in, for example, the seat belt warning system, the ABS braking system, or the engine management system. A control network may have 3 devices, or 300, or 30,000, or more, and can range in complexity from a few smart light switches on a timer to a jet passenger airplane (both of which are examples of existing LonWorks networks). It may be a simple alarm controlled by a remote occupancy sensor, or a city's traffic management system, monitoring and controlling signal lights, traffic flow, the actions of emergency vehicles, power distribution, etc. To many people, control networks are most easily understood as smart houses or home automation. However, most control systems in use today are in commercial buildings and factories doing such things as building cars, computer chips or controlling elevators, lights, and security systems. LonWorks networks are used for all of these and more.

ANSI/CEA-709.1-B Control Networking Protocol

ANSI/CEA-709.1-B Protocol 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 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 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 OSI Layer Purpose Services Provided 7 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 Network Variables; Application Messages; Foreign Frame Transmission; Standard Types 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)

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 Unsigned Long 2 Bytes Network Variable Selector 2 Bytes Service Type ID Transaction Num 1 Byte Addr Format, Domain Length Source Addr (Subnet/Node) Dest Addr (Group) Domain ID (Zero Len Domain) 1 Byte 2 Bytes 1 Byte 0 Bytes Backlog Priority Alt Path 1 Byte 12 Bytes

Layer 1—Physical Layer Electrical interconnect Transmission of raw bits over a communication channel

Physical Layer—Common Channel Types 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 ANSI/CEA-709.4 Yes FO-20S IP-852 ANSI/CEA-852 IP Tunneling N/A ANSI/CEA-852 PL-20A CENELEC A-band Power Line 2613bps LONMARK Interoperability Guidelines PL-20C CENELEC C-band Power Line w/access protocol 156.3k/3987bps ANSI/CEA-709.2 PL-20N CENELEC C-band Power Line w/o access protocol TP/FT-10 Free Topology Twisted Pair 78.13kbps ANSI/CEA-709.3 TP/RS485-39 RS-485 Twisted Pair 39.06kbps EIA/TIA-232-E TP/XF-1250 Transformer-Isolated Twisted Pair

Typical Channel Capacities PL-20x Channels PL-20N ~20 packets/sec PL-20C ~18 packets/sec PL-20A ~11packets/sec TP/FT-10 Channel Peak: ~225 packets/sec Sustained: ~180 packets/sec TP/XF-1250 Channel Peak: ~720 packets/sec Sustained: ~576 packets/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 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—TP/FT-10 Link Power LPT-11 Device Power and network data carried over a common twisted wire pair Power is supplied by a common central power supply No power supplies required in any of the devices in the network when used with the LPT-11 Link Power Transceiver Supports free topology wiring architecture LPT-11 Device 48VDC Power Supply LPI-10 Link Power Interface LPT-11 Device LPT-11 Device LPT-11 Device LPT-11 Device

Physical Layer—PL-20 Channel Advanced technology for reliable communication Dual carrier frequency operation Digital signal processing Worldwide operation Meets FCC, Industry Canada, Japan MPT, and European CENELEC EN50065-1 regulations regulations ANSI/CEA-709.2 compliant European utility support Dual frequency DSP performance in the A-Band for AMR/DSM applications Available in cost-effective device-on-a-chip Transceiver, application processor, memory Proven technology Millions of devices installed worldwide C-Band 115kHz 132kHz A-Band 75kHz 86kHz

Layer 2—Link Layer 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 Features CRC error checking Media access—predictive p-persistent CSMA Priority Collision avoidance

Link Layer—Media Access Predictive p-persistent CSMA Channel access is always randomized over time slots Number of time slots are varied based on collision avoidance algorithm 16 to 1008 slots Non-priority Slots Packet Busy Channel Packet Cycle

Link Layer—Media Access Priority Packet 1 2 3 n ... Priority Slots Busy Channel Packet Cycle Non-priority Slots Configurable priority messages Reserved time slot Reduces overall channel bandwidth Priority slot number is assigned at installation time No collisions possible during priority portion of packet cycle following preceding packet Highest priority message has predictable response time

Link Layer—Media Access Benefits Linear response time over 99% of channel bandwidth Critical for open media such as power line Remove and attach devices without halting communications Predictable performance for high-priority messages

Link Layer—709.1 MAC vs. Ethernet from: Computer Networks, Andrew S. Tanenbaum, Fourth Edition, 2003.

Layer 3—Network Layer Message delivery How data frames are routed from a source device to one or more destination devices Physical address 48-bit Neuron ID—used for initial configuration 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 1 SUBNET 1 127 1 SUBNET 2 127 1 SUBNET 3 127 GROUP 1 1 SUBNET 4 127 1 SUBNET 255 127 DOMAIN (32,385 Devices)

Network Layer—Addressing Modes Address Mode Address Format Destination Address Size (bytes) Domain-wide Broadcast Domain (Subnet = 0) All devices in the domain 3 Subnet-wide Broadcast Domain, Subnet the subnet Unicast Domain, Subnet, Node Specific device within a subnet 4 Multicast Domain, Group the group Neuron ID Domain, Neuron-ID 9 Optimize bandwidth with multiple addressing modes Application communications only requires 3- or 4-byte network addresses 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 18,446,744,073,726,329,086 domains 255 subnets per domain 127 devices per subnet 32,385 devices per domain 256 groups per domain 64 devices per acknowledged group 32,385 devices per unacknowledged group

Network Layer—Routers Domain Subnet 1 Subnet 2 Subnet 1 ... Channel Router Repeater Group 1 Router Subnet 5 Subnet 3 Group 1 Router Repeater Group 2 Subnet 4 Extend channel segments Improve reliability Increase overall bandwidth Simplify network configuration Routers are transparent to devices and applications

Layer 4—Transport Layer End-to-end reliability—allows reliable delivery of message packets Three message delivery services Acknowledged Sending device requires acknowledgment from all receiving devices All acknowledgments are end-to-end Automatic retries if acknowledgement not received Repeated Configurable number of messages per transaction Conserves bandwidth with large groups Better response time Three repeats provides > 99.999% probability of delivery Unacknowledged One message per transaction Conserves network bandwidth and provides highest performance Duplicate detection prevents repeated messages to the application S R Acknowledged - Unicast R R R S R Acknowledged - Multicast S R Repeated- Unicast or Multicast S R Unacknowledged - Unicast or Multicast

Layer 5—Session Layer Adds control to the data exchanged by the lower layers Request/response service Used for device management, fetching values, and requesting other remote actions Authentication Verifies identity of message sender… S R R R R S R

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 Verifies identity of message sender Uses a 48-bit secret key known by each device Sender must provide correct reply to 64-bit random challenge from the receiver

Layer 6—Presentation Layer 23 Room Temp Set Point Temp Temp Sensor (Made in USA) Setpoint Display (Made in Korea) Boiler System (Made in Europe) Data exchanged using network variables Propagation automatically handled by Neuron firmware Provides fastest and most compact code Devices from different manufacturers can exchange data with a common interpretation

Presentation Layer—Connections Motion Room Occupied Feedback Brightness Motion Detector Lamp 0% - 100% Key Code Control Knob Alarm Intruder Arm / Disarm Key Pad Alarm Bell Sensors “publish” information, and actuators “subscribe” to information Devices are logically connected Connections do not affect device applications

Presentation Layer—Standard Types 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 Ensures consistent data presentation in tools and HMIs Example A SNVT_temp_p value of 2940 is displayed as follows: 29.4 degrees C 84.9 degrees F 52.9 degrees F

Layer 7—Application Layer 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 Alarming Data logging Scheduling More than 60 others

Application Layer—Application Configuration 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 Configuration Properties Optional Network Variables nvoStatus SNVT_obj_status nv2 nvoAlarm2 SNVT_alarm_2 nv10 nvoDateResync SNVT_switch nv11 nvoAlarm SNVT_alarm nv4 nvoFileStat SNVT_file_status nv6 nvoFileDirectory SNVT_address nv8 nviRequest SNVT_obj_request nv1 nviTimeSet SNVT_time_stamp nv3 nviDateEvent SNVT_date_event nv9 nviFileReq SNVT_file_req nv5 nviFilePos SNVT_file_pos nv7 nvoLogStat SNVT_log_status nv13 nviLogReq SNVT_log_req nv12 Mandatory 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 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