File talk:Classful-IPv4-networks.webm

Video is out-of-date

Earlier today Renepick left the following note on my talk page:

classful ip addresses

hey W163 in the article en:Internet_protocol_suite you commented "the video explains "classfull" IP addresses, but we've been using "classless" IP addresses for over 20 years now". I am not sure if I understand you correctly. We are using en:Classless_Inter-Domain_Routing but IP adresses still come with a network class even though these networks might be divided into further subnets? How and where exactly do you see the need for an update? maybe you could give your feedback and thoughts on the talk page of the video on commons File:Classful-IPv4-networks.webm best --Renepick (talk) 00:38, 23 October 2013 (UTC)

And so, as suggested, I'm continuing the discussion here.

Basically the idea of a classful world where IP addresses are divided into class A, B, and C is obsolete. The classful concept has been replaced with the classless approach and classes are no longer relevant other than as a historical curiosity. Classlessness was introduced with RFC 1338 in June 1992. I can't think of a case where the class of an IP address is still used today. The size of address blocks given out is no longer limited to the number of blocks in a class. Routing no longer uses the class of an address to determine the network portion of the address. So, explaining classful addresses without explaining the idea of classless addresses and routing is confusing. Even explaining class based addresses together with the concept of classless routing seems unnecessarily complex. My suggestion is to skip explaining the class based concept and move on and explain classlessness instead. I might throw in a discussion of subnet masks too.

--Jeff Ogden, W163 (talk) 02:41, 23 October 2013 (UTC)

Here is what the lead to the classful network article says:

A classful network is a network addressing architecture used in the en:Internet from 1981 until the introduction of en:Classless Inter-Domain Routing in 1993. The method divides the address space for Internet Protocol Version 4 (en:IPv4) into five address classes. Each class, coded in the first four bits of the address, defines either a different network size, i.e. number of hosts for en:unicast addresses (classes A, B, C), or a en:multicast network (class D). The fifth class (E) address range is reserved for future or experimental purposes.

Since its discontinuation, remnants of classful network concepts remain in practice only in limited scope in the default configuration parameters of some network software and hardware components (e.g., default en:subnet mask), but the terms are often still used erroneously by people working in IT.

--Jeff Ogden, W163 (talk) 02:41, 23 October 2013 (UTC)