ITU-T G.9991
ITU-T G.9991, provisionally known as G.vlc, is an international standard developed by the International Telecommunication Union Telecommunication Sector (ITU-T) for high-speed line-of-sight optical networking, commonly referred to as Light Fidelity (LiFi).[{{Cite web |title=Li-Fi and Other Visible Light Communications (VLC) Standards |url=https://www.connectivity.technology/2023/10/lifi-and-other-visible-light.html |access-date=2025-05-01 |website=www.connectivity.technology}}]
LiFi gained attention after Harald Haas’s 2011 TED Talk[{{Cite AV media |url=https://www.youtube.com/watch?v=NaoSp4NpkGg |title=Wireless data from every light bulb {{!}} Harald Haas |date=2011-08-02 |last=TED |access-date=2025-05-01 |via=YouTube}}] demonstrated data transmission via visible light, sparking interest in optical wireless communication as a secure and spectrum-efficient alternative to RF. The ITU-T, recognizing the potential of VLC, began exploring standardization to ensure interoperability and scalability.
In 2016, the ITU-T Study Group 15 (SG15) began developing G.9991 under the G.hn standard family to define physical and data link layers for VLC systems. The standard was developed to define a physical layer (PHY) and data link layer (DLL) for VLC systems, ensuring high-speed, secure communication using visible light (380–780 nm). The first version of G.9991 was published in March 2019, specifying data rates up to several Gbps, support for multiple users, and integration with existing lighting infrastructure.
Since its initial release, G.9991 has been updated to refine its specifications, including support for infrared (IR) light in addition to visible light, to enhance performance and reduce interference from ambient light. The standard leverages Orthogonal Frequency Division Multiplexing (OFDM) and supports features like spatial multiplexing and wavelength division multiplexing (WDM) to increase capacity.
G.9991 emerged alongside the IEEE 802.11bb LiFi standard (published in 2023), creating a competitive landscape. While 802.11bb aligns with WiFi ecosystems and focuses on VLC for higher theoretical speeds (up to 9.6 Gbps), G.9991 prioritizes secure, stable deployments, with speeds typically in the multi-gigabit range.[{{Cite web |last=Jungnickel |first=Volker |date=2023-03-13 |title=IEEE 802 Standards on Light Communication |url=https://mentor.ieee.org/802.11/dcn/23/11-23-0277-01-0000-ieee-802-standards-on-light-communication.pdf |url-status=live |access-date=2025-05-01 |website=IEEE Org}}] The theoretical speeds 802.11bb have not been realized, and existing products built to G.9991 have been faster.[{{Cite web |date=2020-12-25 |title=Li Fi Rewind 2020 |url=https://www.lifitn.com/blog/2020/12/19/li-fi-rewind-2020 |access-date=2025-05-01 |website=LiFi |language=en-GB}}]
Several companies are at the forefront of developing and commercializing LiFi products that adhere to the ITU G.9991 standard. The most prominent among them are:
Signify (formerly Philips Lighting)[{{Cite web |title=Trulifi |url=https://www.signify.com/en-in/innovation/trulifi |access-date=2025-05-01 |website=Signify |language=en}}]
- Signify is widely recognized as a global leader in lighting and has been a major driver in the adoption of the ITU G.9991 standard for LiFi. Their Trulifi product line is explicitly based on G.9991, offering high-speed, secure, and reliable wireless communication via IR light. Signify has deployed its TruLiFi line, based on G.9991, in a variety of enterprise and government settings. {{Cite web |title=Netherlands Implements “LiFi” Technology for Secure Ammunition Operations |url=https://www.defensemirror.com/news/37982/Netherlands_Implements____LiFi____Technology_for_Secure_Ammunition_Operations |access-date=2025-05-01 |website=www.defensemirror.com}}(e.g., Dutch Ministry of Defense)
- The company emphasizes leveraging existing lighting infrastructure for LiFi, making adoption more cost-effective and scalable.
- Oledcomm, based in France, is another key player using ITU G.9991 in its LiFi solutions. Oledcomm markets LiFi equipment using ITU-style “baseband” chipsets, and its products are designed for high-speed, secure communications in environments such as factories, offices, and public spaces.
- Oledcomm’s LiFiMAX and Soleris product lines are positioned for aerospace,{{Cite web |title=Ariane 6 launches LIFI: light-speed secure communications |url=https://www.esa.int/Enabling_Support/Space_Transportation/Ariane/Ariane_6_launches_LIFI_light-speed_secure_communications |access-date=2025-05-01 |website=www.esa.int |language=en}} cable replacement, and secure office communications.
- Oledcomm is a proponent of the G.9991 standard.
Fraunhofer Heinrich Hertz Institute (Fraunhofer HHI)[{{Cite web |title=LiFi Standardization |url=https://www.hhi.fraunhofer.de/en/departments/pn/research-groups/metro-access-and-in-house-systems/lifi-standardization.html |access-date=2025-05-01 |website=www.hhi.fraunhofer.de}}]
- Fraunhofer HHI has played a significant role in the research and development of G.9991-compliant LiFi systems. The institute was among the first to develop USB-operated LiFi systems with high data rates and low power consumption.
- Fraunhofer HHI continues to contribute to standardization and product development in the LiFi sector.
- Terra Ferma, a US manufacturer of LiFi and Power Over Ethernet products, is a newcomer in the LiFi space. Terra Ferma markets their LiFi solutions for Government and Military applications. Their products are designed for high-speed, secure communications in sensitive environments such as Government offices, laboratories, and military operations.
- Terra Ferma has two product lines: Helios and Fortis. The Helios line of products are designed for secure, indoor applications while the Fortis line meets Military Standards 810-H and 461-G for outdoor and military use.
Other LiFi Vendors and Research Groups: Multiple vendors and academic groups have adopted G.9991, leveraging its compatibility with G.hn chipsets and its robust, standardized approach to optical wireless networking.
HomeGrid Forum[{{Cite web |title=HomeGrid Forum – Any wire. Anywhere. It just works. |url=https://homegridforum.org/ |access-date=2025-05-01 |language=en-US}}]
The HomeGrid Forum, which promotes G.hn standards, supports G.9991 adoption. Members like MaxLinear and Microchip Technology integrate G.9991 into their chipsets for LiFi-enabled devices, targeting smart homes, industrial IoT, and enterprise networks. These chipsets enable manufacturers to build G.9991-compliant LiFi solutions.
- Multiple chipset vendors already support G.996x and are extending their support to G.9991, ensuring that LiFi products can interoperate with a broad ecosystem of existing networking devices.
- This hardware compatibility accelerates adoption and simplifies integration into mixed-media environments.
Enterprise and Industrial Sectors:
Companies in sectors requiring secure, RF-free communication—such as manufacturing, healthcare, and finance—use G.9991-based systems. {{Cite web |title=What is Li-Fi and Could It Be the Future of the Internet? |url=https://www.cnet.com/home/internet/what-is-li-fi/ |access-date=2025-05-01 |website=CNET |language=en}}For instance, G.9991 is deployed in factories to connect IoT devices without RF interference, and in hospitals to avoid disrupting sensitive medical equipment.
Government and Defense:
Government agencies and defense organizations adopt G.9991 for its security benefits. The standard’s line-of-sight nature prevents signal interception, making it ideal for secure communication in sensitive environments. The Dutch Ministry of Defense uses Signify’s TruLiFi (based on G.9991) for secure office connectivity. {{Cite web |last=Media |first=OpenSystems |title=Communication pact for DoD signed between Intelligent Waves and Signify - Military Embedded Systems |url=https://militaryembedded.com/comms/communications/communication-pact-for-dod-signed-between-intelligent-waves-and-signify |access-date=2025-05-01 |website=militaryembedded.com |language=en}} The US Government has implemented Terra Ferma LiFi Access Points and Controllers into several Government and Military Projects.
----{{Short description|ITU-T standard for indoor line-of-sight optical networking}}
ITU-T G.9991 (provisionally known as G.vlc) is a standard developed by ITU-T for line-of-sight optical networking.{{Cite web |last=Hollister |first=Sean |date=2023-07-15 |title=Infrared may no longer be a punchline, as IEEE approves 9.6Gbps wireless light |url=https://www.theverge.com/23795599/li-fi-wi-fi-802-11-bb-internet-of-light |access-date=2023-07-17 |website=The Verge |language=en-US}}{{Cite web |last=Eggmayr |first=Bernadette |date=2020-01-01 |title=ITU-T G.9991 (aka G.VLC) Activities in 2020 |url=https://www.eliot-h2020.eu/itu-t-g-9991-aka-g-vlc-activities-in-2020/ |access-date=2023-07-17 |website=ELIoT |language=en-GB}}
G.9991 was approved in March 2019.{{Cite web |title=ITU-T Recommendation database |url=https://www.itu.int/itu-t/recommendations/rec.aspx?rec=13781 |access-date=2023-07-17 |website=ITU |language=en}}
References
{{reflist}}
See also
- IEEE 802.11bb, an IEEE standard for line-of-sight optical networking approved in 2023
- IrDA, an early low-speed infrared communication protocol
- IEEE 802.1X
- IEEE 802.1AE
{{networking-stub}}