Talk:OSI model

SIP -- both Layer 7 and Layer 5?

The Article includes SIP in both the Application Layer (Layer 7) and the Session Layer (Layer 5), both in the table and in the right-hand-side box. Is this and error or was this deliberate? The Wikipedia page for SIP and RFC 3261 both state that SIP is an Application-layer protocol. Rahul (talk) 07:47, 22 November 2010 (UTC)

SPDY in session layer??

SPDY is listed in the session layer. But the main article for SPDY describes it as an application-level protocol (and it solves the same problems as HTTP/HTTPS, which are app-level). Does someone know if its placement in session layer is correct? — Preceding unsigned comment added by 98.217.176.221 (talk) 17:28, 28 May 2011 (UTC)

Corrected. -- Tomtefarbror (talk) 16:51, 28 August 2011 (UTC)

Internet Engineering Task Force (IETF)

Many questions raised in the Discussion would be answered by including a column in the Examples table, for IETF RFCs. An IETF columns belongs in it, anyway.

FWIW IETF is the source of information used for writing ANSI specs. ANSI determines what the U.S. contributes to ISO specs. Kernel.package (talk) 18:58, 14 June 2011 (UTC)

Edit request from Scottghall, 20 July 2011

The graphics in the can be more legible by using this graphic:

http://bcamca.in/wp-content/uploads/2011/04/osi-model.png

Scottghall (talk) 22:08, 20 July 2011 (UTC)

Question: Does that image have a copyright? If so it can be uploaded to the commons and then requested again to be put into the article. See Wikipedia:Uploading images for more information. Jnorton7558 (talk) 23:39, 20 July 2011 (UTC)

Unhelpful help

Section Layer 1: Physical Layer, second paragraph – the paragraph actually confuses more than it clarifies. The trouble is that the reasoning "think of Layer 1 as 1 connection, but Layer 2 as 2 or more connections" confuses numerics with meta thinking – it's more informative to explain that Layer 2 peruses and remedies problems occuring in Layer 1. I don't like the paragraph. The section is better without it. Rursus dixit. (^mbork³!) 08:33, 27 July 2011 (UTC)

Capitalized layers

Hi, I don't see why the layers (layer 1, physical layer etc.) should be capitalized. While they certainly are established concepts they are not proper names. I would like to correct that. Thanks, --EnOreg (talk) 10:14, 13 September 2011 (UTC)

If you don't see why, then please study the subject matter and the defining documents, and don't presume to just come here and changes things out of ignorance. Too many people come to WP and want to make changes to things they don't understand quite obviously. Kbrose (talk)

Yes, they are proper nouns: they are the names of the OSI layers. They are used in this article to refer to the specific layers of the OSI protocol and no others. — Dgtsyb (talk) 18:09, 13 September 2011 (UTC)

But they are not themselves the protocol. The protocol probably qualifies to be a proper noun, and therefore to be upcased, but the generic components of such a protocol (used in other protocols, I presume) are like "computer": downcased. There is every reason not to upcase "physical layer" and "data link layer". Otherwise, the whole point of upcasing gets watered down and starts to be meaningless to our readers.

BTW, I am surprised that the "m" in the article title isn't upcased, since it's a proprietary name, isn't it. And the opening line is weird: "The Open Systems Interconnection model (OSI model) is a product of the Open Systems Interconnection effort ...". Surely "Model" is part of the name. If it were "An Open Systems Interconnection model", sure, you'd use "m", or possibly downcase the entire item (i.e., one of many such models, or so widespread that it has lost the ownership/specificity that underpinned the original capitals, like hoovering the carpet, not Hoovering the carpet).

BTW, why is "X.200" boldfaced?

PS User:EnOreg pointed me here, since we've been discussing capitalisation in this area, and I've been looking at the sorry state of the MoS subpage on this field. Tony (talk) 02:22, 14 September 2011 (UTC)

You presume wrong: they are not used in other models. Referring to "layer 7" has no meaning in this context. OTOH, "Layer 7" is the "Application Layer". You will not see any lowercasing even in the talk page, (except here). Also, they are capitalized in X.200 even though ITU is famous for lower-casing nouns that they coined themselves. — Dgtsyb (talk) 03:56, 14 September 2011 (UTC)

As far as OSI model is concerned, ITU refers to it in X.200 as the "Reference Model" or the "Basic Reference Model", capitalized. So that should probably be changed to "OSI Reference Model". — Dgtsyb (talk) 04:00, 14 September 2011 (UTC)

The layer names are most certainly proper names, they are the defined names of these layers in OSI, alongside with the numbered versions. And no, model is not part of the name of the concept. It is a model with the adjective OSI but not more. It is very tiresome to see inexperienced editors in these subject matters come every few months or years and try to change or question what has been hashed over many times. Simply, if you don't understand the subject matter, just stay away, you are causing more waste of time than anything else. Kbrose (talk) 04:05, 14 September 2011 (UTC)

• Kbrose, sorry, you're showing distinct signs of WP:OWNERSHIP, but this is not going to go away, so I ask that you treat other editors with a little more dignity. You can feel it's tiresome for as long as you like, but please hold the insults about inexperienced editors. On your specific point, you haven't convinced me that "model" isn't part of the proper noun: there's only one of these, isn't there? It's unique, and a title. It's odd that you think on the other hand that the numbered layers need a cap (I don't disagree).

  Dgtsyb, it's generally considered polite not to start with "You presumed wrong": you also seem to be showing early signs of ownership. When you say, "You will not see any lowercasing even in the talk page", that is more likely to make me draw the opposite conclusion. Please remember that WP's readership is much wider than the experts and professionals in a particular area, and that maximising the use of caps for no good reason aside from the fact that people on this talk page might do it, and some publications haven't thought it through, needs to be questioned. On the specifics, "Layer 7", yes, caps there would be endorsed by a wide range of style guides, and WP's own house style (although many would be happy with the lowercase option). But "physical layer" is not unique to this model, surely? The distinction needs to be made, if so. Tony (talk) 04:13, 14 September 2011 (UTC)

The "Physical Layer" is unique to this model, which all experts in the subject matter understand. — Dgtsyb (talk) 19:14, 14 September 2011 (UTC)

These things have nothing to do with ownership, but knowledge and experience. Again, you are showing you are lacking such and should be content with reading and learning not editing. Many systems have physical layers, but when the subject is the Physical Layer, it is the instance of such a concept in OSI. TCP/IP on the other hand doesn't have a Physical Layer definition, but it is assumes a physical layer underneath the model. These usages are really completely covered by standard English rules for common and proper nouns. A common problem on WP occurs when people take details from technical reference works in which certain terms are defined as proper names with definitive meaning in the framework of the specification and write self-standing articles without properly specifying or building the context within which these terms are in fact proper nouns. Kbrose (talk) 04:26, 14 September 2011 (UTC)

I am not accusing you of ignorance in English-language style, or sloppiness (even though you don't seem to notice the inadequacies of the article in those respects). So please don't accuse me: "Again, you are showing you are lacking such and should be content with reading and learning not editing" and the extraordinary, "just stay away, you are causing more waste of time than anything else". They are rude, gratuitous insults that border on the xenophobic, and the more you persist, the more you'll see of me. You need to take a check of your attitude, and you'll also need to get used to justifying upper-case usage where there's doubt. I do appreciate your expertise, BTW: thank you for explaining. But I'm not yet sure that I accept your conclusions: if many systems have physical layers, why is this particular physical layer a Physical Layer? Why do you say "model" should be in lower case in the title, then? It just doesn't seem logical. And I note that the first caption has "OSI-Model" and "layers 3 to 5": huh? And "Example" in the middle, with a wrong upper-case E. You can imagine why other editors are starting to ask questions. There are other stylistic glitches littered through the article, too; for example, why do we have "Service Data Unit (SDU)" but then "protocol data unit (PDU)", in the same sentence, if you please? If the articles in this field are so sloppy and inconsistent, why are you spinning out when people come in to assist? Sounds like it's a certain advantage not to be in the field, in that respect, but expert–outside collaboration is clearly needed. So, again, cut the rudeness and engage with us civilly, please. Tony (talk) 04:41, 14 September 2011 (UTC)

These issues in capitalization results from people that know nothing of the context of the usage coming in an changing capitalization here and there from time to time, like now, destroying the consistent usage in the entire article. If you would like to clean it up, Capitalizing Everything would be a better start that lower-casing everything. — Dgtsyb (talk) 19:17, 14 September 2011 (UTC)

I'll try to summarize the arguments we have so far on whether the layers are proper nouns.

• Proper nouns:
  • (1) They are the names of the OSI layers, referring to the specific layers of the OSI protocol and no others. E.g., the "Physical Layer" is unique to this model.
  • (2) They are capitalized in X.200 even though ITU is famous for lower-casing nouns that they coined themselves.
• Not proper nouns:
  • (3) The layers are generic and applied to other protocols.

I would argue as follows. The actual OSI protocols were a failure—they never played any practical role in the industry. But the reference model caught on and has been widely used to classify any protocol into one of the layers. Therefore, the layers have become generic networking terms that do not qualify as proper nouns.

A Google search produces corroborating evidence, suggesting that the vast majority of university lectures and research papers spell the layers in lower case. The same is true for the educational material by one of the largest vendors, Cisco. Even more strikingly, the standard textbooks on the subject, most prominently Tanenbaum as well as Peterson & Davie, use the lower case. Unlike standards documents, textbooks undergo rigorous copy-editing by language experts. All this seems to make a strong case for lower-case layers. --EnOreg (talk) 14:05, 17 September 2011 (UTC)

Wow! Are you saying that the relative failure or adoption rate of an ISO standard determines whether the nouns in WP articles are proper or not? I didn't see that reasoning in WP:CAPS. ;) — Dgtsyb (talk) 01:30, 19 September 2011 (UTC)

Nah, that is mostly background information. Please consider the entire argument. --EnOreg (talk) 09:21, 21 September 2011 (UTC)

Are there any other arguments we're missing? Or are the arguments I laid out above convincing? --EnOreg (talk) 15:37, 28 September 2011 (UTC)

If there are no more objections let's change the layers to lower case. --EnOreg (talk) 10:19, 3 October 2011 (UTC)

I object: they are proper nouns. — Dgtsyb (talk) 18:12, 3 October 2011 (UTC)

The layer names are clearly proper nouns, they are the given names of the defining characteristics of the standard. You name your son John or Shorty, you capitalize it. The Moon is our companion, despite many other planets having a moon, too. Kbrose (talk) 00:11, 4 October 2011 (UTC)

Then let's hear your arguments. I've presented mine on September 17, countering the previous ones for proper nouns. How do you argue against these? --EnOreg (talk) 08:38, 5 October 2011 (UTC)

It's been a month since the arguments for proper nouns have been refuted and no new ones have been presented since. That leaves really no reason not to adapt the article to the spelling commonly found in the literature on the subject. --EnOreg (talk) 15:42, 16 October 2011 (UTC)

The arguments were not refuted. They are proper nouns and must stand. — Dgtsyb (talk) 02:30, 17 October 2011 (UTC)

On September 17 I summarized all arguments pro caps I could find in this discussion and presented arguments that I think refute both of them. Since then no counter-arguments have been presented. If you think the pro arguments were not refuted you need to say either which pro argument I missed, or which part of my refutation failed to convince you and why. Only repeating your conclusion doesn't count. You need to reveal your arguments to have a grown-up discussion. --EnOreg (talk) 20:21, 17 October 2011 (UTC)

Having not read all the above, I simply consulted books, and found that the layer "names" are not typically treated as proper names: [1], [2], [3], [4] generic; [5], [6] capitalize "Application" etc. but not "layer"; in the first page of 10 google book hits for OSI and "Application Layer", exactly zero show evidence of treatment of "Application Layer" as a proper name. For OSI and "Physical Layer", did find one out of ten: [7] (it also includes "The Lemon-Pudding Layer", so clearly a great moist source). Dicklyon (talk) 04:22, 18 October 2011 (UTC)

Lacking any credible support for the assertion "they are proper names", and lots of evidence of generic lowercase usage in reliable sources about the OSI model, I think it's time for a multiple RM on the various capitalized "Layer" articles, and corresponding fixes to this one. EnOreg, you want to start that, or should I when I have time to read WP:RM about to do a multiple move request? Dicklyon (talk) 19:49, 18 October 2011 (UTC)

OK, I have gone ahead and started a multiple RM at Talk:Physical Layer#Requested move, multiple. Dicklyon (talk) 03:46, 19 October 2011 (UTC)

Thanks Dicklyon. --EnOreg (talk) 07:34, 19 October 2011 (UTC)

Odd that nobody has bothered to oppose the multiple move, given all the assertions above. Dicklyon (talk) 23:20, 25 October 2011 (UTC)

Since the moved happened, I went ahead and did a first-pass case correction here. If I got anything wrong, please tweak it. Dicklyon (talk) 18:57, 26 October 2011 (UTC)

PPTP is session layer or data link layer??? Please fix contradiction

If you look at the table at top right corner of the article, PPTP belongs to "session layer". If you look down in the table with examples, PPTP belongs to the "data link layer". I am not sure, where it belongs more, but please fix it ASAP. --Sena (talk) 08:49, 14 September 2011 (UTC)

Well, it seems that PPTP belongs to the "data link layer". You can find it in this table OSI_model#Examples and in lots of places in internet. If nobody will object it, I will move PPTP to the data link level in 7 days. --Sena (talk) 08:31, 15 September 2011 (UTC)

No, it is not listed as at the link layer in OSI, only for TCP/IP as in the comparison in the table. In pure OSI it literally cannot be below a connection-oriented layer, e.g. Transport Layer, since it requires the services of TCP. Please make no changes out of ignorance or what other dubious sources may lead you to conclude. Kbrose (talk) 15:44, 15 September 2011 (UTC)

Ah, OK. Thanks for explanations. Now I get it. PPTP is on the "data link" level for the TCP/IP "mapped" on OSI model. So, in the top-right table it is shown in pure OSI model. Great, but I think this must be somehow better explained. First quick look shows some kind of contradiction. --Sena (talk) 16:45, 15 September 2011 (UTC)

7 layer model

I hear many people calling this model the 7 layer model, could someone please redirect that term (seven layer model) to this page? — Preceding unsigned comment added by 89.138.50.78 (talk) 10:03, 10 October 2011 (UTC)

These exist: Seven-layer model, Seven-layer OSI model. Dicklyon (talk) 19:43, 18 October 2011 (UTC)

"History" - what about a date?

The "history" section doesn't mention even a single date... — Preceding unsigned comment added by 80.174.219.223 (talk) 16:58, 14 November 2011 (UTC)

datagram service model?

In the section OSI model#Cross-layer functions, the description of Multiprotocol Label Switching (MPLS) states, "It was designed to provide a unified data-carrying service for both circuit-based clients and packet-switching clients which provide a datagram service model." There are two ambiguities with this:

1. Dangling participle error: What provides the datagram service model? Is the provider one or more of the clients, the data carrying service, or the MPLS function being described?
2. What is a datagram service model? That phrase does not appear in any other articles and it is not defined in context.

Will an MPLS expert please revise this? Stephen Charles Thompson (talk) 21:19, 24 January 2012 (UTC)