Nessum, previously HD-PLC (short for 'High Definition

Power Line Communication Power-line communication (PLC) is the carrying of data on a conductor (the ''power-line carrier'') that is also used simultaneously for AC electric power transmission or electric power distribution to consumers. A wide range of power-line comm ...

'), is a communication technology standardized by the Institute of Electrical and Electronics Engineers (

IEEE The Institute of Electrical and Electronics Engineers (IEEE) is an American 501(c)(3) organization, 501(c)(3) public charity professional organization for electrical engineering, electronics engineering, and other related disciplines. The IEEE ...

). It is standardized as IEEE 1901-2020. The standard is to be used to communicate data over wired and

wireless Wireless communication (or just wireless, when the context allows) is the transfer of information (''telecommunication'') between two or more points without the use of an electrical conductor, optical fiber or other continuous guided transm ...

media using high frequencies between ~500kHz and ~56 MHz bands. The Nessum Alliance is the certifying body for compatibility between Nessum-based communication devices.

Overview

Nessum offers two types of communication: wired (Nessum WIRE) and wireless (Nessum AIR).

Wired communication

Nessum WIRE can be used for various types of wires such as

power lines Electric power transmission is the bulk movement of electrical energy from a generating site, such as a power plant, to an electrical substation. The interconnected lines that facilitate this movement form a ''transmission network''. This is ...

twisted pair Twisted pair cabling is a type of communications cable in which two conductors of a single circuit are twisted together for the purposes of improving electromagnetic compatibility. Compared to a single conductor or an untwisted balanced ...

wiring, coaxial cables, and

telephone line A telephone line or telephone circuit (or just line or circuit industrywide) is a single-user circuit on a telephone communication system. It is designed to reproduce speech of a quality that is understandable. It is the physical wire or oth ...

s. The communication distance can range between tens of meters to several kilometers depending on the use case. In addition, when an automatic relay function called multi-hop (ITU-T G.9905) is utilized, a maximum of 10 stages of relay is possible to extend the range, and support various network topologies (

Ring (The) Ring(s) may refer to: * Ring (jewellery), a round band, usually made of metal, worn as ornamental jewelry * To make a sound with a bell, and the sound made by a bell Arts, entertainment, and media Film and TV * ''The Ring'' (franchise), a ...

Star A star is a luminous spheroid of plasma (physics), plasma held together by Self-gravitation, self-gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sk ...

Bus A bus (contracted from omnibus, with variants multibus, motorbus, autobus, etc.) is a motor vehicle that carries significantly more passengers than an average car or van, but fewer than the average rail transport. It is most commonly used ...

MESH Medical Subject Headings (MeSH) is a comprehensive controlled vocabulary for the purpose of indexing journal articles and books in the life sciences. It serves as a thesaurus of index terms that facilitates searching. Created and updated by th ...

). With a maximum physical speed of 1 Gbps and effective throughput ranging from several Mbps to several hundred Mbps, this technology is used to reduce network construction costs and complexity by utilizing the existing lines or dedicated lines.

Wireless communication

Nessum wireless communication is called Nessum AIR. It uses magnetic field communication for short range communication. The communication distance can be controlled in the range of a few centimeters to 100 centimeters. Maximum physical speed is 1 Gbps, with an effective speed of 100 Mbps.

Technical overview

Physical layer (PHY)

The

physical layer In the seven-layer OSI model of computer networking, the physical layer or layer 1 is the first and lowest layer: the layer most closely associated with the physical connection between devices. The physical layer provides an electrical, mechani ...

uses Wavelet

OFDM In telecommunications, orthogonal frequency-division multiplexing (OFDM) is a type of digital transmission used in digital modulation for encoding digital (binary) data on multiple carrier frequencies. OFDM has developed into a popular scheme for ...

(Wavelet Orthogonal Frequency Division Multiplexing), while a guard interval is required in ordinary OFDM systems. The Wavelet

system eliminates the guard interval and increases the occupancy rate of the data portion, thereby achieving high efficiency. In addition, due to the bandwidth limitation of each subcarrier, the level of sidelobes is set low, which facilitates the formation of spectral notches. This minimizes interference with existing systems and allows for flexible compliance with frequency utilization regulations. Furthermore,

Pulse-Amplitude Modulation Pulse-amplitude modulation (PAM) is a form of signal modulation in which the message information is encoded in the amplitude of a pulse train interrupting the carrier frequency. Demodulation is performed by detecting the amplitude level of th ...

(PAM) is used for each subcarrier, and the optimal number of modulation multi-levels is set according to the conditions of the transmission path, thereby improving transmission efficiency. The frequency band used can be selected from among standardized patterns.

Data link layer (MAC)

The

data link layer The data link layer, or layer 2, is the second layer of the seven-layer OSI model of computer networking. This layer is the protocol layer that transfers data between nodes on a network segment across the physical layer. The data link layer p ...

manages

quality of service Quality of service (QoS) is the description or measurement of the overall performance of a service, such as a telephony or computer network, or a cloud computing service, particularly the performance seen by the users of the network. To quantitat ...

and other control functions using control frames "beacons" broadcast periodically by the parent to all terminals in the network. The basic media access methods are Carrier-Sense Multiple Access with Collision Avoidance (

CSMA/CA Carrier-sense multiple access with collision avoidance (CSMA/CA) in computer networking, is a link layer multiple access method in which carrier sensing is used. Under CSMA/CA, nodes attempt to avoid collisions by beginning transmission only af ...

) and Dynamic Virtual Token Passing (DVTP), which dynamically assign transmission rights to terminals in the network and avoid collisions, The system uses a collision avoidance mechanism.

Specification and features

There are essentially two different types of HD-PLC: HD-PLC Complete and HD-PLC Multi-hop. They are incompatible.

HD-PLC Complete

Source: This is for high speed applications such as TV, AV, and surveillance cameras. The major technical features include: * IEEE 1901 full compliant * QoS by the priority control *

and DVTP(Dynamic Virtual Token Passing) supported * Concurrent multi-AV stream, VoIP, and file transfer and file transfer supported using IP packet classification * Multi-network access at priority

with network synchronization

HD-PLC Multi-hop

Source: This is for long-distance applications such as smart meter, building network, factory, energy management, and IoT devices. The major technical features include: * ITU-T G.9905 multihop technology

Common features

Source: * Uplinking/downlinking through 432 of 26 MHz (between 1.8 MHz and 28 MHz) bandwidth subcarriers with Wavelet OFDM * Maximum 240 Mbit/s PHY rate * Multilevel modulation for each subcarrier which suits the properties of the power line transmission channel and allows for the best transmission speed * Subcarrier masking with the arbitrary number which can comply with the rules in each country * Forward error correction (FEC) which enables effective frame transmission * Channel estimation launch system with change detector for cycle and transmission channel * HD-PLC network bridging compatible to Ethernet address system * Advanced encryption with 128 bit AES

4th-generation HD-PLC (HD-PLC Quatro Core technology)

Source: We now come to communication speed issues like high-definition video images (4K/8K) or in some cases multi hop technology is not enough to reach an isolated and distant PLC terminal. HD-PLC Quatro Core has been designed to solve these problems. This technology is an improvement on the conventional HD-PLC in both communication distance and speed. It achieves to double conventional HD-PLC's communication distance by adopting a communication band of 1/2 or 1/4 of conventional HD-PLC band and achieves to offer a maximum physical line transmission rate of 1 Gbit/s by using an expanded communication band 2 or 4 times the conventional HD-PLC band. This evolution of the standard therefore offers either an extended range in a larger building, at the cost of a lower data rate, or a higher data rate, but achievable over shorter distances than in the previous version of the standard.

Use cases

There are a few strengths of using HD-PLC technology on existing wires. * Expectable higher speed performance * Cost reduction on network construction by existed infrastructure * Support the area where the radio waves is difficult to be reached * Wire saving by sharing power lines and communication lines Typical use case include: *

HVAC Heating, ventilation, and air conditioning (HVAC ) is the use of various technologies to control the temperature, humidity, and purity of the air in an enclosed space. Its goal is to provide thermal comfort and acceptable indoor air quality. ...

systems *

Building Automation Building automation (BAS), also known as building management system (BMS) or building energy management system (BEMS), is the automatic centralized control of a building's HVAC, HVAC (heating, ventilation and air conditioning), electrical, light ...

* Photovoltaic (solar) panel communications * Smart metering * Meter to grid communications * Smart street lighting * Surveillance camera systems * Video entry systems * Communications in tunnels * Robot wiring optimisation

Nessum Alliance

Nessum Alliance was established in September 2007 as a voluntary association, originally under the name of "HD-PLC Alliance". In October 2023, the HD-PLC Alliance was renamed the Nessum Alliance.{{Cite press release , url=https://www.businesswire.com/news/home/20231003535815/en/HD-PLC-Alliance-is-renamed-Nessum-Alliance-as-it-enters-a-New-Era-of-Wired-and-Wireless-Any-Media-IoT-Communication-Applications%21 , title="HD-PLC Alliance" is renamed "Nessum Alliance" as it enters a New Era of Wired and Wireless (Any Media) IoT Communication Applications! , website=businesswire , date=4 October 2023 , accessdate=2023-10-13 Nessum Alliance is a certifying body for compatibility between communication devices that comply with the international standard IEEE 1901-2020. Associated organisations are the Japanese

Telecommunication Technology Committee The Telecommunication Technology Committee (TTC; ) is a standardization organization established in 1985 and authorized by Japan's Ministry of Internal Affairs and Communications to conduct research and to develop and promote standards for telecomm ...

(TTC) The Taiwanese

Industrial Technology Research Institute The Industrial Technology Research Institute (ITRI; ) is a technology research and development institution in Taiwan. It was founded in 1973 and is headquartered in Hsinchu, Hsinchu City, Taiwan, with branch offices in the United States, U.S., ...

and the

IEEE Standards Association The Institute of Electrical and Electronics Engineers Standards Association (IEEE SA) is an operating unit within IEEE that develops global standards in a broad range of industries, including: power and energy, artificial intelligence systems, ...

. At the outset of Q2 2025 the Nessum Alliance listed 41 member companies and organisations.

History

This technology is based on HD-PLC, a type of

power line communication Power-line communication (PLC) is the carrying of data on a conductor (the ''power-line carrier'') that is also used simultaneously for AC electric power transmission or electric power distribution to consumers. A wide range of power-line comm ...

developed by

Panasonic is a Japanese multinational electronics manufacturer, headquartered in Kadoma, Osaka, Kadoma, Japan. It was founded in 1918 as in Fukushima-ku, Osaka, Fukushima by Kōnosuke Matsushita. The company was incorporated in 1935 and renamed and c ...

in the early 2000s. HD-PLC was developed for room-to-room transmission of audio and video data at the time, but later began to be used not only for power lines but also for coaxial lines and twisted pair lines, and even for wireless communication. The name "power line communication" did not match the reality of the situation. In September 2023, Panasonic Holdings Corporation changed the name of HD-PLC to Nessum.

References

External links

Nessum Alliance
Computer networking