ITU-T home networking recommendations
Common name Recommendations
HomePNA 2.0 G.9951, G.9952, G.9953
HomePNA 3.0 G.9954 (02/05)
HomePNA 3.1 G.9954 (01/07)
G.hn G.9960, G.9961
G.hn-management G.9962
G.hn-mimo G.9963
G.hn-psd G.9964
G.vlc G.9991
G.cx G.9972
G.hnta G.9970
G.dpm G.9977
G.sa G.9978
G.cwmp (TR-069) G.9980

Gigabit Home Networking (G.hn) is a specification for wired home networking that supports speeds up to 2 Gbit/s and operates over four types of legacy wires: telephone wiring, coaxial cables, power lines and plastic optical fiber. Some benefits of a multi-wire standard are lower equipment development costs and lower deployment costs for service providers (by allowing customer self-install).[1]

G.hn offers enhanced immunity to power line disturbances compared to other connection technologies. It serves as a bridge, connecting older systems prevalent in industrial settings with modern technologies that can revolutionize operations. While many machines and devices have transitioned to wireless, wired legacy systems remain integral for communication in industrial contexts. In the industrial realm, swift and dependable connectivity is crucial for seamless machine-to-machine interactions. Absence of this can lead to operational halts or reduced service quality. G.hn stands as a pivotal infrastructure for time-sensitive and safety-critical tasks, boasting strong features that support vital communications and a network's ability to auto-recover. [2]

History

G.hn was developed under the International Telecommunication Union's Telecommunication Standardization sector (the ITU-T) and promoted by the HomeGrid Forum and several other organizations. ITU-T Recommendation (the ITU's term for standard) G.9960, which received approval on October 9, 2009,[3] specified the physical layers and the architecture of G.hn. The Data Link Layer (Recommendation G.9961) was approved on June 11, 2010.[4]

Prominent organizations, including CEPca, HomePNA, and UPA, who were creators of some of these interfaces, rallied behind the latest version of the standard, emphasizing its potential and significance in the home networking domain.[5] Moreover, the ITU-T extended the technology with multiple input, multiple output (MIMO) technology to increase data rates and signaling distance.[6] This new feature was approved in March 2012 under G.9963 Recommendation.

The development and promotion of G.hn have been significantly supported by the HomeGrid Forum and several other organizations.[7] The technology was not only designed to address home-networking challenges but also found applications beyond this initial scope, showcasing its versatility and potential in the networking domain.[8]

Technical specifications

Technical overview

G.hn specifies a single physical layer based on fast Fourier transform (FFT) orthogonal frequency-division multiplexing (OFDM) modulation and low-density parity-check code (LDPC) forward error correction (FEC) code. G.hn includes the capability to notch specific frequency bands to avoid interference with amateur radio bands and other licensed radio services. G.hn includes mechanisms to avoid interference with legacy home networking technologies[9] and also with other wireline systems such as VDSL2 or other types of DSL used to access the home.

OFDM systems split the transmitted signal into multiple orthogonal sub-carriers. In G.hn each one of the sub-carriers is modulated using QAM. The maximum QAM constellation supported by G.hn is 4096-QAM (12-bit QAM).

The G.hn media access control is based on a time division multiple access (TDMA) architecture, in which a "domain master" schedules Transmission Opportunities (TXOPs) that can be used by one or more devices in the "domain". There are two types of TXOPs:

Optimization for each medium

Although most elements of G.hn are common for all three media supported by the standard (power lines, phone lines and coaxial cable), G.hn includes media-specific optimizations for each media. Some of these media-specific parameters include:[10]

Security

G.hn uses the Advanced Encryption Standard (AES) encryption algorithm (with a 128-bit key length) using the CCMP protocol to ensure confidentiality and message integrity. Authentication and key exchange is done following ITU-T Recommendation X.1035.[12]

G.hn specifies point-to-point security inside a domain, which means that each pair of transmitter and receiver uses a unique encryption key which is not shared by other devices in the same domain. For example, if node Alice sends data to node Bob, node Eve (in the same domain as Alice and Bob) will not be able to easily eavesdrop their communication.[13]

G.hn supports the concept of relays, in which one device can receive a message from one node and deliver it to another node farther away in the same domain. Relaying becomes critical for applications with complex network topologies that need to cover large distances, such as those found in industrial or utility applications. While a relay can read the source and target addresses, it cannot read the message's content due to its body being end-to-end-encrypted.

Profiles

The G.hn architecture includes the concept of profiles. Profiles are intended to address G.hn nodes with significantly different levels of complexity. In G.hn the higher complexity profiles are proper supersets of lower complexity profiles, so that devices based on different profiles can interoperate with each other.[14]

Examples of G.hn devices based on high complexity profiles are Residential Gateways or Set-Top Boxes. Examples of G.hn devices based on low complexity profiles are home automation, home security and smart grid devices.

Technical parameters

The chart depicts a summary of the crucial technical specifications of the G.hn standard. Many of these technical elements are consistent across different physical media, with variations seen in areas such as Tone Spacing and frequency ranges. This uniformity is essential as it allows silicon manufacturers to produce a singular chip capable of implementing all three media types, leading to cost savings. Presently, G.hn chipsets are compatible with all three media types. This compatibility allows system manufacturers to create devices that can adjust to any wiring type simply by modifying a software configuration in the equipment.[15]

Spectrum

The G.hn spectrum depends on the medium as shown in the diagram below:

G.hn spectral usage

Protocol stack

G.hn protocol stack

G.hn specifies the physical layer and the data link layer, according to the OSI model.[10]

The interface between the Application Entity and the Data Link Layer is called A-interface. The interface between the Data Link Layer and the physical layer is called Medium Independent Interface (MII). The interface between the physical layer and the actual transmission medium is called Medium Dependent Interface (MDI).

Support

HomeGrid Forum

The HomeGrid Forum is a non-profit trade group promoting G.hn.[16]

HomeGrid Forum members include:[17]

Promoters Contributors Adopters
AT&T 3 Rivers Communications Actiontec Electronics, Inc.
Bayernwerk BC Institute of Technology ARRIS Solutions, Inc.
CenturyLink Bell Aliant Allion Labs, Inc.
China Telecom[18] Bell Canada CIG Shanghai Co. LTD.
China Unicom[19] CAICT COMTREND Corporation
ISSI Connexion Technologies ENPROTECH
KT Corporation Consolidated Communications HOMA Technologies JSC
Chunghwa Telecom DBS Satellite Services Methode Electronics
Liberty Global[20] devolo AG[21] Nokia
MaxLinear EATELCORP, Inc. SendTek Corporation
Telus GVT Technicolor USA, Inc
Verizon Hawaiian Telcom Teleconnect GmbH
GVT TRIAX A/S
Hawaiian Telcom UVAX Concepts, S.L.
Highland Communication Services Xingtera Inc.
Logic Communications
Lucerne University (HSLU)
Moapa Valley Telephone
MTCC
New Hope Telephone Cooperative
Northeast Louisiana Telephone Co., Inc.
Phonoscope
Randolph Telephone Membership Corporation
Rural Telephone Service Co.
Sandwich Isles Communicationes
Smithville Telecom, LLC
Tata Sky Ltd.
TBayTel
Telecom Italia S.P.A.
Triangle Communications
The University of British Columbia
Universidad de Malaga
University of Johannesburg
University of Science Ruhr West
ZHAW – Zurich University of Applied Sciences

Vendors

Vendors promoting G.hn include MaxLinear, ReadyLinks Inc, Lantiq, devolo AG, microprocessor manufacturer Intel,[22] system-on-a-chip vendor Sigma Designs,[23] and Xingtera, which announced a product in January 2013.[24]

The first live public demonstration of G.hn interoperability was shown at CES, January 10–13, 2012 by Lantiq, Marvell Technology Group, Metanoia, and Sigma Designs.[25]

Service providers

On February 26, 2009, as part of a HomePNA press release, AT&T (which makes use of wireline home networking as part of its U-Verse IPTV service) expressed support for the work developed by ITU-T creating standards for home networking, including G.hn.[26]

Service providers like AT&T promoted G.hn for:[27]

Other service providers that are contributors to the work ITU-T Study Group include British Telecom,[28] Telefónica, and AT&T.

Equipment vendors

In April 2008, during the first announcement of HomeGrid Forum, Echostar, a manufacturer of set-top boxes for the service provider market, expressed its support for the unified standard:[29]

Consumer electronics

In March 2009, Best Buy (which is the largest retailer of consumer electronics in the United States) joined the board of directors of HomeGrid Forum and expressed its support for G.hn.[30]

Panasonic, one of the largest manufacturers of consumer electronics, is also a contributor member of HomeGrid Forum.

Analysts

In 2008, several marketing firms promoted G.hn and made optimistic predictions.[31][32][33]

Other organizations

In July 2009, HomeGrid Forum and DLNA signed a liaison agreement "setting the stage for collaboration between the two organizations and the approval of G.hn as a DLNA-recognized Physical Layer technology".[34]

In June 2010, Broadband Forum and HomeGrid Forum signed an agreement to deliver a compliance and interoperability testing program for products using G.hn technology. The Broadband Forum will support HomeGrid Forum's validation of G.hn products, their promotion of product conformance and interoperability, and help expedite the total time to market for HomeGrid Forum Certified products.[35] In May 2011, both organizations jointly announced the first open G.hn plugfest.[36]

Related standards

Relationship between G.hnta and G.hn

ITU G.9970 (also known as G.hnta) is a Recommendation developed by ITU-T that describes the generic architecture for home networks and their interfaces to the operators' broadband access networks.

ITU G.9972 (also known as G.cx) is a Recommendation developed by ITU-T that specifies a coexistence mechanism for home networking transceivers capable of operating over power line wiring. The coexistence mechanism would allow G.hn devices which implement G.9972 to coexist with other devices implementing G.9972 and operating on the same power line wiring.

ITU G.9991 (also known as G.vlc) is a Recommendation developed by ITU-T that specifies the PHY and DLL for High speed indoor visible light communication transceivers, used in applications such as Li-Fi. G.vlc reuses the PHY and DLL of G.hn, enabling the same chips to be used for both applications.

Residential applications

The major motivation for wired home networking technologies was IPTV, especially when offered by a service provider as part of a triple play service, voice and data service offering such as AT&T's U-Verse.[37] Smart grid applications like home automation or demand side management can also be targeted by G.hn-compliant devices that implement low-complexity profiles.[38]

  1. IPTV: In many customers' homes the residential gateway that provides Internet access is not located close to the IPTV set-top box. This scenario becomes very common as service providers start to offer service packages with multiple set-top boxes per subscriber. G.hn can connect the residential gateway to one or more set-top boxes, by using the existing home wiring. Using G.hn, IPTV service providers do not need to install new Ethernet wires, or 802.11 wireless networks. Because G.hn supports any kind of home wiring, end users might install the IPTV home network by themselves, thus reducing the cost to the service provider.[39]
  2. Home networks: Although Wi-Fi technology is popular for consumer home networks, G.hn is also intended for use in this application. G.hn is an adequate solution for consumers in situations in which using wireless is not needed (for example, to connect a stationary device like a TV or a network-attached storage device), or is not desired (due to security concerns) or is not feasible (for example, due to limited range of wireless signals).
  3. Consumer electronics: Consumer electronics (CE) products can support Internet connectivity using technologies such as Wi-Fi, Bluetooth or Ethernet. Many products not traditionally associated with computer use (such as TVs or hi-fi equipment) provide options to connect to the Internet or to a computer using a home network to provide access to digital content. G.hn is intended to provide high-speed connectivity to CE products capable of displaying high-definition television. Integrating the power connection and the data connection provides potential energy savings in CE devices. Given that CE devices (such as home theater receivers) very often run on standby or "vampire power", they represent major savings to homeowners if their power connection is also their data connection - the device could reliably be turned off when it is not displaying any source.
  4. Smart grid: Because G.hn can operate over wires including AC and DC power lines, it can provide the communication infrastructure required for smart grid applications. A comprehensive smart grid system requires reaching into every AC outlet in a home or building so that all devices can participate in energy conserving strategies. In September 2009, the US National Institute of Standards and Technology included G.hn as one of its standards for the smart grid "for which it believed there was strong stakeholder consensus", as part of an early draft of the "NIST Framework and Roadmap for Smart Grid Interoperability Standards".[40] In January 2010 G.hn was removed from the final version of the "Standards Identified for Implementation".[41]

Industrial applications  

G.hn technology facilitates the connection of devices across various network types using different wiring options, including coax, phone lines, power lines, and optical fiber. Initially designed for home networking, its applications expanded to encompass a broad spectrum of industrial scenarios.[15]

  1. Smart elevators: Contemporary elevators are equipped with numerous sensors and actuators that ideally communicate via IP. Leveraging G.hn for communication between these dispersed IP nodes can lead to significant reductions in wiring during installation.
  2. Intelligent lighting systems: In the realm of smart cities, lighting systems are evolving into interactive platforms that interact with their surroundings. This might encompass nodes linked to street signage, light modulation, water monitoring, atmospheric sensors, pedestrian communication systems, vehicle charging stations, imaging units, and audio systems.
  3. Airport navigation lights: Utilizing the right signal coupler allows the existing infrastructure to be repurposed with the G.hn PLC profile, simplifying the communication system setup.
  4. Charging stations: Charging station networks, encompassing quick payment, user-friendly queries, operations, station oversight, and cloud-based control, can efficiently repurpose existing powerline infrastructure for data transfer.
  5. Industrial facilities: G.hn components can be integrated to function alongside industrial control systems through the power bus. The employment of coaxial cables is seen as beneficial due to their durability in challenging conditions, reducing the need for protective conduits.
  6. Fiber solutions for harsh conditions: G.hn access systems come with an industrial profile, allowing them to function in challenging conditions like flooding or extreme temperature fluctuations.

The ITU-T endorsed G.hn technology stands out as today's most adaptable and dependable network backhaul for multi-gigabit connectivity, spanning from residential and business applications to industrial and smart grid scenarios. G.hn is consistently advancing across various media, including coax, copper pairs, powerlines, and plastic optical fibers, as well as LiFi communication systems using visible light, ultraviolet, and infrared spectrums. This supports the industry's digital transformation. HomeGrid Forum members champion the worldwide adoption of G.hn, a unified networking technology with multiple sources.

See also

References

  1. ^ HomeGrid Forum Webinar: In-Stat's Perspective on Integrated, Segregated & Next-Generation Wired In-Home Networks[permanent dead link]
  2. ^ Rosu, Livia (2021). "G.hn is opening the door to new industrial opportunities". IoT Now.
  3. ^ New ITU standard opens doors for unified 'smart home' network, ITU Press Release
  4. ^ United Nations ITU-T's G.hn Approved as Global Standard for Wired Home Networking
  5. ^ "Technology Organizations Align to Support United Nations' ITU-T G.hn Standard: CEPCA, HomePNA, and UPA Unite with HomeGrid Forum to Promote Next-Generation Home Networking Technology". Press release. HomeGrid Forum. February 25, 2009. Archived from the original on March 10, 2009. Retrieved December 1, 2013.
  6. ^ a b Ben-Tovim, Erez (February 2014). "ITU G.hn - Broadband Home Networking". In Berger, Lars T.; Schwager, Andreas; Pagani, Pascal; Schneider, Daniel M. (eds.). MIMO Power Line Communications: Narrow and Broadband Standards, EMC, and Advanced Processing. Devices, Circuits, and Systems. CRC Press. doi:10.1201/b16540-16. ISBN 9781466557529.
  7. ^ HomeGrid Forum (2021). "G.hn in Home Networking". HomeGrid Forum.
  8. ^ ISE MAG (2022). "G.hn and CATV Coexistence". ISE MAG.
  9. ^ HomeGrid Forum White-paper: G.hn Compatibility with Existing Home Networking Technologies Archived May 9, 2010, at the Wayback Machine, HomeGrid Forum Blog
  10. ^ a b HomeGrid Forum - G.hn Technology Overview[permanent dead link], (registration required)
  11. ^ G.9963 (2015) Amd 1
  12. ^ "Top Ten Things You Need to Know About the New G.hn Standard". Archived from the original on May 26, 2009. Retrieved May 13, 2009.
  13. ^ "An introduction to G.hn security". Archived from the original on October 14, 2009. Retrieved September 22, 2009.
  14. ^ Updated Issues List for G.hn - Geneva May 2009[permanent dead link], (ITU membership required)
  15. ^ a b HomeGrid Forum (2023). "White Paper G.hn Industrial IoT Use Cases" (PDF). HomeGrid Forum.
  16. ^ ITU-T G.hn Specification Achieves Key Milestone with Successful Consent at Geneva ITU-T Meeting Archived February 7, 2009, at the Wayback Machine, Significant Progress Towards Unified Standard for Home Networking Endorsed by HomeGrid Forum
  17. ^ "Our Members – HomeGrid Forum".
  18. ^ "China Telecom Shanghai Research Institute joins the HomeGrid Forum to support G.hn technology deployment in Asia – HomeGrid Forum".
  19. ^ "HomeGrid Forum welcomes China Unicom Research Institute and CAICT as new members supporting G.hn in China ahead of CES ASIA 2018 – HomeGrid Forum".
  20. ^ "Liberty Global joins HomeGrid Forum as support grows for G.hn standard – HomeGrid Forum".
  21. ^ "HomeGrid Forum member devolo launches G.hn-based devolo Magic: MaxLinear and devolo showcasing new G.hn products with Mesh Wi-Fi at IBC 2018 – HomeGrid Forum".
  22. ^ "Intel publishes white-paper on G.hn standard". Archived from the original on January 2, 2010. Retrieved June 8, 2009.
  23. ^ SIGMA DESIGNS JOINS HOMEGRID FORUM BOARD OF DIRECTORS[permanent dead link]
  24. ^ Xingtera G.hn Device Upgrades Home Networks with Radio Frequency (RF) Over Coax
  25. ^ "HomeGrid - Press Releases and News". Archived from the original on February 8, 2012. Retrieved February 2, 2012.
  26. ^ HomePNA and HomeGrid Sign Liaison Agreement, Groups Work to Promote New ITU G.hn Global Wired Home Networking Standard
  27. ^ HomeGrid Forum Webinar: A Service Provider's Perspective on G.hn Archived August 17, 2009, at the Wayback Machine, Tom Starr, AT&T
  28. ^ BT Joins HomeGrid Forum Board of Directors[permanent dead link]
  29. ^ "Industry Creates HomeGrid Forum to Develop Technology for Enjoying Multimedia Anywhere in the Home". Archived from the original on February 7, 2009. Retrieved April 25, 2009.
  30. ^ HomeGrid Forum Adds New Members, Best Buy Joins Board Of Directors Archived July 19, 2009, at the Wayback Machine, Consumer Electronics Retailer to Help Drive G.hn Technology
  31. ^ New G.hn Home Networking Standard Has Significant Potential Archived December 4, 2008, at the Wayback Machine, ABI Research
  32. ^ "New global standard for fully networked home". Archived from the original on February 21, 2009. Retrieved December 12, 2008.
  33. ^ CopperGate Communications Commits to G.hn
  34. ^ HOMEGRID FORUM SIGNS LIAISON AGREEMENT WITH DIGITAL LIVING NETWORK ALLIANCE[permanent dead link]
  35. ^ Broadband Forum and HomeGrid Forum Reach Definitive Collaboration Agreement With the Aim of Enabling Conformance and Interoperability of G.hn Products
  36. ^ "HomeGrid Forum and Broadband Forum Announce First Open G.hn Chipset Interoperability Plugfest" (PDF). Archived from the original (PDF) on July 24, 2011. Retrieved May 26, 2011.
  37. ^ Multiple industries converging around the G.hn standard Archived June 21, 2009, at the Wayback Machine, HomeGrid Forum Blog
  38. ^ Berger, Lars T.; Iniewski, Krzysztof (April 2012). Smart Grid - Applicacions, Communications and Security. John Wiley and Sons. pp. 1–16. ISBN 978-1-1180-0439-5. 712376.
  39. ^ "Why do we need a unified standard at all?" Archived June 22, 2009, at the Wayback Machine, HomeGrid Forum Blog
  40. ^ "Commerce Secretary Unveils Plan for Smart Grid Interoperability". Archived from the original on June 25, 2012. Retrieved July 13, 2017.
  41. ^ NIST Smart Grid Interoperability Standards Roadmap