IrDA

8 hours ago

Light has been used for communication since early methods like signal fires and fiber optics, highlighting free-space optical (FSO) communications as a less common but functional option.
FSO technologies, including laser links for satellites and systems like Li-Fi, have existed for decades but remained niche until recent satellite constellations like Starlink popularized them.
Hewlett-Packard (HP) developed infrared protocols like RedEye and HP SIR for calculator-printer communication, evolving into the IrDA standard in 1993 for short-range wireless networking.
IrDA standardized a protocol stack including physical layers (e.g., SIR, MIR, FIR), link layers (IrLAP for discovery), and higher layers like IrLMP and TinyTP for multiplexing and flow control.
Application protocols over IrDA included IrCOMM for serial emulation, IrJetSend for printing, and OBEX for file and data transfer, enabling features like business card exchange between devices.
IrDA faced limitations like point-to-point connections due to optical constraints, lack of multipoint support, and competition from Bluetooth and Wi-Fi, leading to its decline by the mid-2000s.
Despite obsolescence in consumer electronics, IrDA persists in embedded applications due to low cost, security advantages, and regulatory benefits, with protocols like IrLAN exploring IP networking over infrared.

Hasty Briefsbeta