Talk:IP address

This is the talk page for discussing improvements to the IP address article.
This is not a forum for general discussion of the subject of the article.

Add new text under old text.
New to Wikipedia? Welcome! Learn to edit; get help.

Start a new topic

Article policies

Find sources: Google (books · news · scholar · free images · WP refs) · FENS · JSTOR · TWL

Archives (index): 1, 2, 3, 4: 6 months

Computing: Networking High‑importance

	This article is within the scope of WikiProject Computing, a collaborative effort to improve the coverage of computers, computing, and information technology on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.ComputingWikipedia:WikiProject ComputingTemplate:WikiProject ComputingComputing
High	This article has been rated as High-importance on the project's importance scale.
	This article is supported by Networking task force (assessed as Top-importance).

Internet High‑importance

	Internet portal This article is within the scope of WikiProject Internet, a collaborative effort to improve the coverage of the Internet on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.InternetWikipedia:WikiProject InternetTemplate:WikiProject InternetInternet
High	This article has been rated as High-importance on the project's importance scale.

Additional Reserved IPv4 Subnets Per RFC5737

Latest comment: 2 years ago1 comment1 person in discussion

The IP Address page is protected (and my English is not good enough for editing such a page) so I just like to note that there are 3 more IP addresses subnets that are reserved: https://datatracker.ietf.org/doc/rfc5737/

The blocks 192.0.2.0/24 (TEST-NET-1), 198.51.100.0/24 (TEST-NET-2), and 203.0.113.0/24 (TEST-NET-3) are provided for use in documentation and I think that this should be noted in a separate paragraph. 2A06:C701:4C05:C200:47E2:4FB4:F37A:C580 (talk) 21:35, 26 April 2024 (UTC)Reply

Does 127.0.0.0/8 count as part of class A?

Latest comment: 1 year ago2 comments2 people in discussion

https://www.icann.org/en/system/files/files/inet-tutorial-ajm-18jun02-en.pdf (page 15) implies that it doesn't count as part of class A, and I find it hard to believe that a mistake would stay on ICANN's website for 20 years

If it does count as part of class A, a citation should definitely be added Person568 (talk) 03:17, 14 March 2025 (UTC)Reply

The definition of class A is that the first bit (MSB) is zero (RFC790 page 2). Class B has first two bits 10, class C is 110. Looking at those bits is how computers work out the class. 127.x.x.x has a special purpose but it is class A. Your link shows some slides for a tutorial talk. A tutorial might omit 127 because they don't want to give the impression that it is available for a private network. Johnuniq (talk) 03:46, 14 March 2025 (UTC)Reply

This page was redesigned at the edge.

Additional Reserved IPv4 Subnets Per RFC5737

Does 127.0.0.0/8 count as part of class A?