Talk:List of IP protocol numbers

HEX numbers

I've added the HEX numbers so that it is easier for programmers to look up their protocols. The List is far away from any main path, so it should not bother the normal surfer. If you have any suggestions, please write it here. And please do not delete the HEX values. Musterstudent (talk) 13:26, 27 June 2008 (UTC)

It is not clear how this column helps programmers look up their protocols (maybe in a protocol analyzer but these now do the decode to decimal for you) and whether this is something that we should be trying to achieve here. IANA specifies this in decimal. Because over half of our readers are using mobile devices, we'd like to avoid unnecessary width in tables. ~Kvng (talk) 14:03, 21 December 2024 (UTC)

While adding these hexadecimal numbers is quite redundant I do believe they can be quite useful in some scenarios and are worth keeping. I have encountered myself needing to manually convert decimal from tables to hexadecimal numerous times and it's quite the chore if you just want to get something done quickly. rafa_br34 (talk) 23:50, 27 May 2025 (UTC)

@Rafabr34, can you give us more information on how exactly what scenarios these are helpful? Programming languages let you specify numbers in the base of your choice. Modern protocol analyzers routinely decode into decimal. In what exact context are you needing to use hex for these numbers? ~Kvng (talk) 13:35, 28 May 2025 (UTC)

Personally I like to implement enumerators using hexadecimal for larger sets and binary for smaller sets so for me it's especially useful in that regard. I also have found myself manually dissecting hex streams of network packets and in such cases having some reference to search for and a way to quickly lookup what some value means is very important. rafa_br34 (talk) 15:16, 28 May 2025 (UTC)

@Rafabr34: Your personal preferences have no significance for this article, sorry. --Zac67 (talk) 06:10, 29 May 2025 (UTC)

While I specifically said that it's my personal preference to use hexadecimal numbers to implement enumerators it is also a widely adopted practice along programmers, especially when the enumerator is more than 8-bits wide (not the case here) and/or the "enumerator" is a set of constants that need to manually be defined, for example in linux/fs/9p/v9fs.h and linux/drivers/acpi/acpica/aclocal.h, I could find way more but I hope this is enough to make my point. Obviously a programmer that actually values their code base and how RFC compliant it is, will skip Wikipedia entirely and use a more reliable and professional source like IANA so I guess it doesn't really matter in this specific scenario. rafa_br34 (talk) 07:09, 29 May 2025 (UTC)

@Rafabr34, As an experienced programmer, I understand best practice to be to code those enums in the base in which they are defined and cite the source of the definition in the comments. These definitions are done by IANA in decimal.

I've also had to occasion to dig through hex dumps but programming and debug tools have improved since then so this is not a common exercise today. ~Kvng (talk) 14:29, 29 May 2025 (UTC)

We have in this thread both a compelling reason they might be harmful for mobile viewers, and a compelling reason they might be useful to at least a subset of programmers. It seems to me that programmers are more likely to be reading on desktop than a general audience is, and both concerns might be addressed by using class="nomobile" on the hex column. I've made this change in [1]. Thoughts? DefaultFree (talk) 15:12, 29 May 2025 (UTC)

That's a productive suggestion but I disagree that we have a compelling reason they might be useful to at least a subset of programmers. IME, the subset of programmers referred to are those time traveling from 1995. I'd prefer to remove the column altogether. ~Kvng (talk) 15:29, 29 May 2025 (UTC)

Occurence

What does the occurrence have to do with anything? SurDin (talk) 15:50, 5 February 2009 (UTC)

The Occurrence section was removed by another editor. For those wondering what that was about see this revision of the article. --Marc Kupper|talk 02:47, 27 September 2016 (UTC)

The name of this article is weird

...Why is the name of this article esentially 'Internet Protocol protocol numbers'? Am I missing something here? ^Jguy_Talk^Done 17:00, 12 October 2011 (UTC)

Because the Internet Protocol is itself able to carry different protocols. These protocols are identified by protocol numbers. Protocol appears twice because we have a protocol within a protocol. --Kvng (talk) 19:36, 15 October 2011 (UTC)

I think "IP in IP" is misleading

Protocol 4 is currently listed like this:

Decimal	Hex	Keyword	Protocol	References
4	0x04	IP	IP in IP (encapsulation)	RFC 2003

RFC2003 defines IPv4 tunneled in IPv4. (the iana website also refers to RFC2003 in it's list). However it depend on where the number 4 is used which tunneling protocol is used. If it is in a IPv4 packet, IP in IP is probably the correct link. But in a IPv6 packet, it should link to 4in6. And in a Authentication Headers (AH) or Encapsulating Security Payloads (ESP) it should link to IPsec.

So I think it is better to just call it IPv4 and refer to RFC791. (compare this to protocol 41 - which links to IPv6 and not 6in4 or any other encapsulation protocol):

Decimal	Hex	Keyword	Protocol	References
41	0x29	IPv6	IPv6 (encapsulation)	RFC 2473, RFC 3056

--wimmel (talk) 16:58, 6 April 2012 (UTC)

Sound like this is used for several different applications. I would propose that we add a note to the entry explaining this. Here's the wiki syntax for notes. --Kvng (talk) 14:42, 8 April 2012 (UTC)

Obsolete

It would be helpful to know which of these protocol numbers became obsolete. I suggest to add a column Obsolete with the date or the RFC that made them obsolete. Theking2 (talk) 09:38, 1 July 2013 (UTC)

obsolete is a de-faqto category, finding which rfc caused the last user or potential user to take a course that would not involve that protocol number is very hard. TristanDC (talk) 11:58, 23 July 2023 (UTC)

Value?

This list does not appear to provide any encyclopedic value compared to the list published by IANA. I'm tempted to WP:PROD it to save us the hassle of maintaining it. ~KvnG 17:05, 2 July 2013 (UTC)

One value is that it has wikilinks to articles about each of the protocols. The Internet protocol list is very rarely changed and so the maintenance load is low. --Marc Kupper|talk 02:51, 27 September 2016 (UTC)

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IPsec

Protocols 50 and 51 are, collectively, IPsec.

Would anyone object if I changed:

 0x32 	50 	ESP 	Encapsulating Security Payload 	RFC 4303
 0x33 	51 	AH 	Authentication Header 	RFC 4302

To:

 0x32 	50 	ESP 	Encapsulating Security Payload (IPsec) 	RFC 4303
 0x33 	51 	AH 	Authentication Header (IPsec)	RFC 4302

Regards, Ben Aveling 00:00, 20 September 2019 (UTC)

About protocol 84 duplication

Protocol 84 no longer needs to be listed twice. Sallersanyi (talk) 05:57, 4 November 2023 (UTC)

@Sallersanyi: Thanks – SESU is no WP:RS but IANA is authoritative. Since TTP is freshly obsoleted I've added a remark. --Zac67 (talk) 07:27, 4 November 2023 (UTC)