In telecommunication

Telecommunication

Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded...

s and computer networking, Concrete Syntax Notation One (CSN.1) is a standard

Standardization

Standardization is the process of developing and implementing technical standards.The goals of standardization can be to help with independence of single suppliers , compatibility, interoperability, safety, repeatability, or quality....

 and flexible notation that describes data structures for representing, encoding, transmitting, and decoding data, specifically GPRS used for cell phones. Many examples of CSN.1 encoded data structures can be found in 3GPP

3GPP

The 3rd Generation Partnership Project is a collaboration between groups of telecommunications associations, known as the Organizational Partners...

 TS44.060 and an informative description of the CSN.1 syntax is found in 3GPP

3GPP

The 3rd Generation Partnership Project is a collaboration between groups of telecommunications associations, known as the Organizational Partners...

 TS 24.007.

Here is an example of a CSN.1 description of a message. If the first bit is 1, an apple structure follows, which is a 5-bit Apple code. If the first bit is 0, on the other hand, a 3-bit orange code, and a 2-bit peel type follow.


::= { 1 | 0 } 0;



::= < Apple Code : bit(5) >;



::= ;


Disadvantages

• The notation is not as compact as ASN.1
• It is very difficult to maintain when extensions and new releases of the protocols need to be implemented
• Creating a compiler for the language is very difficult, because the language can include expressions that refer to any named elements previously decoded.
• The CSN.1 structures listed in communication standards are not checked and are often filled with errors and non-standard notation.

See also

• Concrete Syntax Notation Specification
• Annex B of 3GPP TS 24.007 contains a detailed description of CSN.1.
• CSN1.INFO provides a complete online description of CSN.1 (including those parts not explained on TS 24.007), with examples and common pitfalls.