# item.guide
Side-by-Side Comparison Infrared & Optical

IrDA vs. Li-Fi

Comparing 2 standards across 13 specifications. 13 key differences identified.

Comparing:
IrDA
Li-Fi

IrDA is a point-to-point, line-of-sight optical data transmission standard developed by the Infrared Data Association. Operating at 850–900 nm over distances up to 1 meter, it evolved from 115.2 kbps Serial Infrared (SIR) to 4 Mbps Fast Infrared (FIR) and 16 Mbps Very Fast Infrared (VFIR) for wireless printing, laptop file exchange, and mobile synchronization.

View full IrDA spec sheet →

Light Fidelity (Li-Fi, standardized under IEEE 802.11bb in 2023) is a high-speed, bidirectional, fully networked optical wireless communication (OWC) technology. Utilizing invisible infrared (800–1000 nm) or visible LED light emitters, it transmits data at multi-gigabit speeds with zero radio frequency (RF) emissions, immune to electromagnetic interference.

View full Li-Fi spec sheet →

Specification Comparison Table

13 Parameters
Parameter / Spec
Optical Wavelength
850 to 900 nm
Nominal Range
0 to 1.0 m (at ±15° cone angle)
Standard Speed Tiers
SIR (up to 115.2 kbps), MIR (1.152 Mbps), FIR (4.0 Mbps), VFIR (16.0 Mbps), UFIR (96.0 Mbps)
Pulse Encoding (SIR)
Return-to-Zero (RZ) with 3/16th bit duration pulse
Pulse Encoding (FIR)
4PPM (4-Pulse Position Modulation)
Software Protocol Stack
IrLAP (Link Access), IrLMP (Link Management), Tiny TP, IrOBEX (Object Exchange)
IEEE Standard
IEEE 802.11bb-2023
Optical Wavelengths
800 to 1000 nm (Near-Infrared) and 380 to 780 nm (Visible Light Spectrum)
Peak PHY Data Rates
Commercial systems have demonstrated over 1 Gbps; lab demonstrations have reached far higher (a 2021 IEEE study cited up to 224 Gbps), though the 802.11bb standard itself does not fix a single peak rate
Modulation Schemes
OFDM (Orthogonal Frequency-Division Multiplexing) with QAM/DCO-OFDM
Electromagnetic Interference (EMI)
Zero (100% RF-free)
Security Boundary
Physical room containment (Light cannot penetrate opaque walls)
Primary Applications
Hospital surgical suites, defense/government SCIFs, commercial aviation cabin networking, industrial automation