ITU T.50

ITU-T recommendation T.50 specifies the International Reference Alphabet (IRA), formerly International Alphabet No. 5 (IA5), a character encoding. ASCII is the U.S. variant of that character set.

The original version from November 1988 corresponds to ISO 646. The current version is from September 1992.

History

At the beginning was the International Telegraph Alphabet No. 2 (ITA2), a five bits code. IA5 is an improvement based on seven bits bytes.

• 5 T.50 (09/1992) In force
• 4 T.50 (11/1988) Superseded
• 3 T.50 (10/1984) Superseded
• 2 V.3 (11/1980) Superseded
• 1 V.3 (10/1976) Superseded

Use

This standard is referenced by other standards such as RFC 3966.

It is also used by some analog modems such as Cisco ones.^[1]

This standard is referenced by other standards such as RFC 3939 - Calling Line Identification for Voice Mail Messages.

Standardisation

• Identical standard: ISO 646:1991 (Twinned)

References

1. "AT Command Set and Register Summary for NM-8AM-V2, NM-16AM-V2, WIC-1AM, and WIC-2AM Analog Modem WAN Interface Cards - 2: Syntax and Procedures [Cisco 3600 Series Multiservice Platforms] - Cisco Systems". Cisco.com. Retrieved 2012-10-03.

External links

• Official ITU-T T.50 page
• Tech Info - Character Codes (IA5 and ISO 646)