After Li-Fi: What IEEE 802.11br Could Change

IEEE 802.11bb brought light communications into the 802.11 family. The active IEEE P802.11br project asks what the next optical amendment should improve: additional optical bands, new channelization, wavelength-division multiplexing, multi-link operation, optical-front-end integration, ranging support, and compatibility with existing 802.11bb devices.

It is tempting to summarize that work as “faster Li-Fi.” That misses the more interesting direction. P802.11br is about making light a more capable and integrated 802.11 link, not declaring that optical wireless will replace radio.

Where 802.11bb left off

IEEE 802.11bb-2023 defined light communications within the familiar 802.11 MAC framework. It established a standards path for devices to use optical links while retaining concepts that network engineers recognize from Wi-Fi.

Standardization solved an important interoperability and architecture problem. It did not remove the physical characteristics of light. Optical links remain sensitive to transmitter and receiver geometry, obstruction, ambient conditions, device orientation, and the design of uplink as well as downlink.

Those characteristics can be advantages in bounded environments and constraints in mobile ones.

Why IEEE created P802.11br

The approved project scope identifies capabilities beyond the first light-communications amendment. It proposes an enhanced light-communications PHY, changes to the MAC for that PHY and multi-link operation, and compatibility with legacy light-communications devices in the identified bands.

Because P802.11br is an active project, its scope is evidence of what the working group intends to address—not a guarantee that every proposed capability will appear unchanged in a final standard or product.

New optical bands

The project identifies operation in optical ranges from 400 to 600 nanometres and from 1200 to 1600 nanometres. The first spans visible-light wavelengths; the second is in infrared.

Supporting multiple optical regions allows designers to separate communication from visible illumination and to select emitters, receivers, and regulatory constraints suited to the environment. It also reinforces an important terminology point: enhanced light communications is broader than visible-light communication alone.

Wavelength-division multiplexing

Wavelength-division multiplexing uses multiple optical wavelengths as separate channels. The idea is familiar from fibre systems, although a wireless optical implementation faces different propagation, mobility, cost, and front-end constraints.

Within a WLAN amendment, WDM could increase available capacity or support more flexible channelization. Real performance will depend on transmitter and receiver complexity, wavelength separation, optical power, noise, and how effectively devices maintain the link. A scope item is not a field throughput claim.

Multi-link operation

Multi-link operation is particularly relevant because a useful optical network may also have radio links available. A device could potentially use different links according to coverage, capacity, mobility, or obstruction.

This makes hybrid networking more plausible than a simple replacement narrative. Light can provide a high-capacity bounded link where geometry is favourable, while RF maintains continuity when a user moves, blocks the receiver, or leaves the optical cell.

The hard problems are coordination, handover, scheduling, power use, device support, and predictable behavior under changing conditions. Multi-link capability creates options; it does not make those policies automatic.

Optical front ends and implementation

P802.11br includes simpler integration between the 802.11 baseband and optical front ends. That detail may be more commercially important than a headline data rate. A cleaner integration model can reduce the cost and complexity of building interoperable devices.

Adoption depends on components, certification, power, thermal design, form factors, and a reason for manufacturers to include optical hardware. A standard can enable an ecosystem, but it cannot create demand by itself.

Ranging and positioning

The project scope includes PHY support for existing ranging techniques. Because optical coverage can be spatially bounded and associated with known transmitters, light links may contribute to positioning or location-aware services.

That possibility needs careful language. A standards mechanism that supports ranging is not the same as a guaranteed indoor-positioning accuracy. Reflections, receiver placement, calibration, device variation, and environmental conditions affect a real deployment.

What this could mean for deployment

Enhanced light communications may be valuable where radio is constrained, spatial reuse matters, or optical infrastructure already exists. Candidate settings include specialized industrial environments, selected healthcare or aviation contexts, secure bounded rooms, high-density fixed workspaces, and positioning-assisted applications.

Each candidate still needs a complete link budget, uplink plan, mobility design, lighting and eye-safety review, device ecosystem, operations model, and fallback behavior.

The likely architecture is heterogeneous: Ethernet for fixed infrastructure, RF Wi-Fi for broad mobility, and optical links for specific coverage or capacity requirements.

Why commercialization will take time

P802.11br is active standards work. After technical agreement comes implementation, silicon and optical component integration, interoperability testing, certification, device adoption, and deployment learning. Organizations should not purchase against features that exist only in project scope.

The right posture is interest without promotion. IEEE 802.11br could make optical WLANs more flexible through bands, WDM, multi-link integration, and improved implementation paths. Whether that becomes common networking will depend less on laboratory peaks and more on whether products solve a real coverage, capacity, privacy, or interference problem at an acceptable operational cost.