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very fast infrared (VFIR)

Very Fast Infrared (VFIR) is an IrDA technology for point-to-point transmissions. The specifications for infrared transmission set by the Infrared Data Association (IrDA) were increased from 115 kbit/s to 4 Mbit/s

for Fast Infrared (FIR) in the 1990s. In 1999, this data rate was quadrupled to 16 Mbit/s with Very Fast Infrared. In addition, the range, which requires line-of-sight (LOS), was increased to eight meters. The data rate is very dependent on the distance and is 4 Mbit/s at four meters. Later Ultra Fast Infrared (UFIR) was introduced with a data rate of 96 Mbit/s and Giga-Infrared (GIR) with data rates of 512 Mbit/s and 1 Gbit/s

.

Protocol layers of IrDA

Protocol layers of IrDA

Very Fast Infrared uses Non Return to Zero Inverted (NRZ-I) as coding, it has a cyclic block check of 32 bits and a maximum frame length of 2 kB. The VFIR protocol stack consists of three protocols: The IrDA Link Access Protocol (IrLAP), which establishes the infrared link and monitors it throughout the session, the IrDA Link Management Protocol (IrLMP), which supports network services such as printing or faxing, and the IrDA Transport Protocol (IrTP), which can manage multiple data streams

simultaneously.

The different IrDA variants

The different IrDA variants

It is the same protocol stack that Fast Infrared (FIR) uses. This makes VFIR backwards compatible with Fast Infrared.

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Englisch: very fast infrared - VFIR
Updated at: 20.04.2013
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Translations: DE