Terminology » Other Wireless » IrDA vs. WLAN vs. Bluetooth: Wireless Technology Comparison

IrDA vs. WLAN vs. Bluetooth: Wireless Technology Comparison

wireless technology irda wlan bluetooth communication

This article dives into the differences between IrDA (Infrared Data Association), WLAN (Wireless Local Area Network), and Bluetooth technologies. We’ll explore each technology’s characteristics, advantages, and disadvantages, and also examine the IrDA protocol stack.

What is IrDA?

IrDA, or Infrared Data Association, is a non-profit organization dedicated to developing specifications for infrared wireless communication. Founded in 1993, IrDA released its first 1.0 specifications in 1994, supporting data rates up to 115.2 Kbps.

The IrDA protocol stack, which includes SIR, IrLAP, and IrLMP layers, defines how devices communicate. Typically, IrDA supports a range of about 2 meters, establishing a point-to-point, line-of-sight connection between devices. This technology utilizes light wavelengths of 850 to 900 nm for data transmission, using infrared LEDs for communication.

IrDA Security and Applications

IrDA doesn’t inherently provide link-level security. It lacks built-in authorization or authentication, meaning data is transmitted unencrypted. Security relies on software-level implementation. However, the line-of-sight nature of IrDA is often considered relatively secure.

IrDA finds use in various applications including PDAs, mobile phones, printers, cameras, and laptops.

Advantages of IrDA

  • Point-to-Point data communication
  • Line-of-sight application
  • Security (due to line of sight)
  • Low power consumption
  • Low cost

Disadvantages of IrDA

  • Line-of-sight requirement
  • One device at a time

Continuous research and new versions of IrDA aim to overcome these limitations.

IrDA, WLAN, and Bluetooth: A Comparison Table

The following table highlights the key differences between IrDA, WLAN, and Bluetooth:

SpecificationsIrDAWLANBluetooth
IEEE StandardInfrared Data Association Spec.802.11a, 11b, 11g, 11n, 11ac, 11ad802.15.1
Medium of communicationInfrared lightRF wavesRF waves
Coverage range0 to 2 meters20 to 100 meters10 to 100 meters
Network size2 devicesDozens of devices2 to 8 devices
LOS (Line of Sight)YesNoNo
Max. data rate16 Mbps54 Mbps3 Mbps
Power consumptionVery lowHighLow
Interference toleranceExcellentBadGood
Authentication,Authorization, encryptionNot availableavailableavailable

IrDA Protocol Stack

The IrDA protocol stack is structured in layers:

  • IrPHY (Layer 1): The physical layer specifies optical link features, modulation-code rates, CRC, and framing. It defines how data is physically transmitted.
  • IrLAP (Layer 2): The data link layer handles addressing, error detection, and flow control.
  • IrLMP (Layer 3): The network layer manages connections and multiplexing.

On top of IrLMP reside other layers like Tiny TP, IrCOMM, OBEX (Object Exchange Protocol), and IrSimple.

IrDA Data Rates and Modulation

Different modulation and coding techniques enable IrDA to support varying data rates:

  • SIR (Serial Infrared): 9.6 to 115.2 Kbps
  • MIR: 0.576 to 1.152 Mbps
  • FIR (Fast Infrared): Up to 4 Mbps
  • VFIR (Very Fast Infrared): Up to 16 Mbps
  • UFIR: Up to 96 Mbps
  • GigaIR: 512 Mbps to 1 Gbps

IrDA is actively researching even faster speeds, with the creation of the 5/10 Gigabit optical wireless communications workgroup (5/10 GigaIR) to explore new IrPHY implementations for higher data rates.