Extension root

Extension root

In ASN.1, "extension root" is a definition of a type in Version 1 of protocol specification. Extension root acts as a base that can be extended in subsequent revisions of the protocol specification by appending "extension additions" to the end of the extension root or inserting them at a properly defined insertion point. Extension root is usually separated from extension additions by means of the ellipsis character acting as "extension marker". For example, in type definition A ::= INTEGER (0..127, ..., 256..511), 0..127 is extension root, 256..511 is extension additions and ... is an extension marker separating both. In B ::= SEQUENCE { a INTEGER, b INTEGER, ..., c INTEGER, d INTEGER }, definition of fields a and b forms the extension root of type B usually defined in Version 1 specification while fields c and d are extension additions added in subsequent revision of the specification. Type B should have been defined extensible already in Version 1 specification however to make later extensions possible, either explicitly using extension marker as in B ::= SEQUENCE { a INTEGER, b INTEGER, ... }, or implicitly using EXTENSIBILITY IMPLIED directive mentioned in the beginning of the containing ASN.1 module. Variants of the same type B in Version 1 and subsequent revisions of the same specification form "extension series" of this type.


Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Extension — • Philosophical term. From Lat. ex tendere, to spread out Catholic Encyclopedia. Kevin Knight. 2006. Extension     Extension     † …   Catholic encyclopedia

  • root sheath — n the epidermal lining of a hair follicle * * * 1. an epithelial extension of the cervical loop of the enamel organ, consisting of the inner and outer enamel epithelium, and directing the number and morphological growth of the roots. It is… …   Medical dictionary

  • root hair — root′ hair n. bot an elongated tubular extension of an epidermal cell of a root, serving to absorb water and minerals from the soil • Etymology: 1855–60 …   From formal English to slang

  • Root of unity — The 5th roots of unity in the complex plane In mathematics, a root of unity, or de Moivre number, is any complex number that equals 1 when raised to some integer power n. Roots of unity are used in many branches of mathematics, and are especially …   Wikipedia

  • Root Nameserver — globale Anycast Instanz des K Root Servers im AMS IX Root Nameserver, oft auch nur Root Server genannt, publizieren verlässlich die Root Zone des Domain Name Systems (DNS) im Internet. Diese Datei besteht aus ca. 2.500 Einträgen und ist die… …   Deutsch Wikipedia

  • Root name server — A Cisco 7301 router, part of the AMS IX mirror of the K root server. A root name server is a name server for the Domain Name System s root zone. It directly answers requests for records in the root zone and answers other requests returning a list …   Wikipedia

  • Root-Nameserver — globale Anycast Instanz des K Root Servers im AMS IX Root Nameserver, oft auch nur Root Server (was allerdings eine Mehrdeutigkeit zu den Angeboten vieler Server Hoster hat) genannt, publizieren verlässlich die Root Zone des Domain Name Systems… …   Deutsch Wikipedia

  • ROOT — Infobox Software name = ROOT caption = Example ROOT plot showing regions of interest in a 2D distribution developer = CERN latest release version = 5.20/00 latest release date = June 25th, 2008 operating system = Cross platform genre = Data… …   Wikipedia

  • root hair — noun thin hairlike outgrowth of an epidermal cell just behind the tip; absorbs nutrients from the soil • Hypernyms: ↑plant organ • Part Holonyms: ↑root * * * noun : one of the many hairlike tubular outgrowths of epidermal or sometimes cortical… …   Useful english dictionary

  • root — I. noun Usage: often attributive Etymology: Middle English, from Old English rōt, from Old Norse; akin to Old English wyrt root, Latin radix, Greek rhiza Date: 12th century 1. a. the usually underground part of a seed plant body that originates… …   New Collegiate Dictionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”