Dot-decimal notation
Dot-decimal notation is a presentation format for numerical data. It consists of a string of decimal numbers, using the full stop (dot) as a separation character.[1]
A common use of dot-decimal notation is in information technology where it is a method of writing numbers in
IPv4 address
In computer networking, the notation is associated with the specific use of quad-dotted notation to represent IPv4 addresses
An IPv4 address has 32 bits. For purposes of representation, the bits may be divided into four octets written in decimal numbers, ranging from 0 to 255, concatenated as a character string with full stop delimiters between each number.[3] This octet-grouped dotted-decimal format may more specifically be called "dotted octet" format,[6] or a "dotted quad address".[7]
For example, the address of the loopback interface, usually assigned the host name localhost, is 127.0.0.1. It consists of the four octets, written in binary notation: 01111111, 00000000, 00000000, and 00000001. The 32-bit number is represented in hexadecimal notation as 0x7F000001.
No formal specification of this textual IP address representation exists.
A popular implementation of IP networking, originating in
A POSIX-conforming variant of inet_aton, the inet_pton() function, supports only the four-decimal variant of IP addresses.[10]
IP addresses in dot-decimal notation are also presented in
OIDs
Object identifiers use a style of dot-decimal notation to represent an arbitrarily deep hierarchy of objects identified by decimal numbers. They may also use textual words separated by dots, like some computer languages (see inheritance).
Version numbers
Software releases are often given
Libraries
Libraries use notation systems consisting of decimal numbers separated by dots, such as the older Dewey Decimal Classification and the Universal Decimal Classification, to classify books and other works by subject. The UDC additionally codes works with multiple dot-decimal topics, separated by colons.[11]
Texts
Dot-decimal notation is often used for sections within a large text. This was standardized in ISO 2145.
Medicine
Dot-decimal notation is also used to describe illnesses in a language-neutral way. For instance, the
See also
- IPv6 address § Representation
- ISO 2145
- Decimal section numbering
References
- ^ "Gepunktete Dezimalschreibweise". Techplugged (in German).
- ^ "What is Dotted Decimal Notation? - Definition from Techopedia". Techopedia.com.
- ^ a b "IPv4 and IPv6 address formats". www.ibm.com.
An IPv4 address has the following format: x . x . x . x where x is called an octet and must be a decimal value between 0 and 255. Octets are separated by periods. An IPv4 address must contain three periods and four octets. The following examples are valid IPv4 addresses:
1 . 2 . 3 . 4
01 . 102 . 103 . 104 - ^ "Dot address". TechTarget. Retrieved 2010-11-18.
- ^ "Dotted Decimal Notation". encyclopedia.com.[permanent dead link]
- ^ a b c d e Main, Andrew (23 February 2005). Textual Representation of IPv4 and IPv6 Addresses. IETF. I-D draft-main-ipaddr-text-rep-02.
- ^ "Definition of dot address". PCMAG.
- ^ Braden, Robert (1 October 1989). Requirements for Internet Hosts -- Application and Support. IETF. sec. 2.1.
- ^ "Ping and FTP resolve IP address with leading zero as octal". Microsoft Support. Archived from the original on 2006-12-06.
- ^ Linux Library Functions Manual –
- ^ Taylor, Arlene G. (2005). "15: Decimal Classification". Introduction to Cataloging and Classification (PDF) (10th ed.). preprint, to be published by Libraries Unlimited in2006.
- ^ PMID 33328790.
- S2CID 39138324.