2105: Modern OSI Model

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Modern OSI Model

Title text: In retrospect, I shouldn't have used each layer of the OSI model as one of my horcruxes.

Explanation[edit]

The Open Systems Interconnection (OSI) Model is a conceptual model for network communications that defines 7 layers of functionality, where higher layers add increasing complexity to lower layers through associated protocols and standards. The 7 layers in the standard OSI Model are:

  • 7. Application layer: Defines how applications interact with the stack to request and receive information
  • 6. Presentation layer: Defines how one or more sessions are used by endpoints to send and receive a packet of information
  • 5. Session layer: Defines how communication events are initiated and managed in order to successfully transmit information
  • 4. Transport layer: Defines how information is transmitted across the nodes of a network
  • 3. Network layer: Defines how nodes are interconnected to form a network of nodes
  • 2. Data link layer: Defines how data is transmitted across a wired connection
  • 1. Physical layer: Defines the wiring connections between two different nodes

In practice, the OSI model abstracts the communication between two end points, like a Facebook client and Facebook servers all the way from the application layer on the server, down to the wire on which the data is transmitted, and back up to the application layer where the user views the data. As Facebook is one of the most used websites in the world with more than a billion users, Randall claims that the "application" layer (what the client sees and uses) is mostly Facebook.

A light gray shape labeled "Google & Amazon" surrounds all seven layers of the model in an irregular shape indicating that Google and Amazon, by dint of their size and dominance at multiple layers of the model influence the entire structure. An example of Google's influence would be their introduction of new protocols like QUIC and SPDY as replacements for the existing TCP protocol that was a foundation of the web, and their accompanying modifications of the original HTTP protocol.

The significance of the irregular pattern of the "Google & Amazon" blob isn't clear. It is likely that it is in reference to the irregular way in which their modifications to the OSI stack have evolved. Potentially with extensions to the left representing the influence of Google, and extension to the right representing the influence of Amazon. However, it is also notable that the irregular structure of the stack is reminiscent of a Jenga tower. Jenga is a game in which blocks are removed from a vertical stack and added back to the top until the whole collapses. This may be a commentary on the instability of the network stack in general, or on how Google and Amazon's additions and changes to it have destabilized the networking protocols. Or, the specific blocks to be pulled out (presentation, session, and network) may be the ones whose removal collapses the tower while the other ones can be easily removed and replaced (like the center blocks in Jenga), implying that between Google and Amazon, even if these were pulled out, the tower would remain standing. What this says about the three layers that would destabilize the tower is unclear.

The title text refers to Horcruxes used by Voldemort in the Harry Potter book series. A Horcrux is a magical artifact used to house a wizard's soul, preventing them from dying if their body is destroyed. Since they can only be created by murdering other people, they are heavily forbidden, and before Voldemort it was unheard of for a wizard to use more than one. Voldemort used seven -- the same number of layers in the OSI model. However, while Voldemort hid his seven Horcruxes in different places to make himself that much harder to kill, Randall's have all been collected in Google and Amazon, defeating the purpose of using more than one. Alternatively, transforming each layer of the OSI model into a horcrux may be regarded as a strategy to prevent them from being destroyed since doing so would destroy networking. This strategy would fail in the modern world, since some of the envisioned layers were not used in the more common modern TCP/IP networking model and in the case of cloud infrastructure potential exists to provide even more shortcuts.

The title text may also be a reference to a prior comic about Randall mixing up things that come in groups of seven, like data layers and Horcruxes.

Transcript[edit]

[A light gray shape that surrounds seven stacked dark gray rectangles centered above each other, all with labels. The light gray shape is connected but sometimes only on one side of the dark rectangles. It goes above and below the top and bottom rectangles. At the top there is a heading:]
Modern OSI Model
[The first black rectangle has two lines of text. It is supported by the light gray shape on both sides:]
Application (Facebook)
[Pulling the second rectangle out to the right would collapse the tower, with the top tipping to the right:]
Presentation
[Pulling the third rectangle out to the left would collapse the tower, with the top tipping to the left:]
Session
[The fourth rectangle is supported on both sides:]
Transport
[Pulling the fifth rectangle out to the left would collapse the tower making it tip to the left:]
Network
[Between the fifth and sixth dark rectangles is a label for the entire light gray shape:]
Google & Amazon
[The sixth rectangle is supported on both sides:]
Data link
[The seventh rectangle is supported on both sides:]
Physical


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Discussion

Randall seems to be saying that a startup doesn't need to create a new computer system to service their customers, all they have to do is put up a Facebook page which uses Google to find products and then has Amazon deliver them. The middle layer "Transport" is a joke because Amazon literally ships physical boxes, but the OSI model is not about actual boxes; it's about information and the way the information is presented to the user vs what goes on behind the scenes. But I don't get the part about the horcruxes. Is it just the fact that there are seven of them? Or is there some subtle connection I'm missing here? 162.158.106.180 05:50, 30 January 2019 (UTC)

'Transport' has nothing to do with Amazon, in this case, though the juxtaposition is amusing; also, the networking model has nothing to do with the user interface. The seven layers are from the 'standard' OSI networking model, which was introduced in the late 1970s to describe how networking systems work (or were expected to at the time). In practice, the Internet Protocol Suite model is used, which has more or less the same ideas despite evolving separately, though with only four formal layers (Link, Internet, Transport, and Application) instead of seven (Physical, Data Link, Network, Transport, Session, Presentation, and Application).
In the OSI model, the Transport layer is Layer 4 (going up from the lowest level, Physical) and represents the part responsible for checking the consistency of data delivery - that is to say, it decides whether or not to check for dropped packets, and whether to resend dropped ones. In the actual Internet model, the rough equivalent is the Transmission Control Protocol (for 'connected' transmissions which do check and resend) and User Datagram Protocol (for 'connectionless' ones which don't). 172.68.78.10 16:29, 30 January 2019 (UTC)
(Spoilers alert) Voldemort uses signifying objects of his life, heritage and his school's founders as horcruces. When the OSI layers are used as horcruces, one problem would be that Google/Amazon would have taken control of two horcruces, the other that some of the layers are frayed at the sides. Randall should not have put his horcruces in living standards - that was a very dangerous move. Sebastian --172.68.110.46 07:54, 30 January 2019 (UTC)
Even worse: Some of the horcruxes have apparently merged.Gunterkoenigsmann (talk) 15:51, 28 March 2019 (UTC)

Is there a meaning of the widths of the layers - not a block or a triangle/pyramid? Are there more layers than the named ones? Or the named ones multiple times? This would correspond to the design of ever more layers, virtualizations, abstractions and overall complexity of computer systems as time moved forward. Sebastian --172.68.110.46 07:49, 30 January 2019 (UTC)

It looks like a jenga tower to me. 162.158.89.223 12:35, 30 January 2019 (UTC)
Could some reference to this, or at least some speculation on the irregularity of the tower on general, be added? I would propose something like the following:
The significance of the irregular pattern of the Google/Amazon blob isn't clear. It is likely that it is in reference to the irregular way in which their modifications to the OSI stack have evolved. However, it is also notable that the irregular structure of the stack is arranged so as to resemble a Jenga tower. Jenga, for those unfamiliar, is a game in which blocks are added and removed from a vertical pile until the whole collapses. This may be a commentary on the instability of the stack in general, or on how Google and Amazon's additions and changes to it have destabilized the networking protocols. -- 172.68.78.10 16:00, 30 January 2019 (UTC)
I think you may be reading too much into the shape, it looks much more irregular than a Jenga tower. If anything I would guess it's just a rough reflection of how much influence Google and Amazon have at each level -- more Google influence means the blob goes farther left, more Amazon influence means it goes farther right.

I think Google & Amazon are the grey blob that is slowly absorbing all of the layers 141.101.107.114 07:55, 30 January 2019 (UTC)

Excellent remark! Google & Amazon are inserted between the Data Link and Network layers, and while it seems like an eight layer from the shape profile, they do not sit in their own bordered rectangle. Another view point is maybe Randall tried to display the fight between the Infrastructure providers to capture a new layer in gestation. 141.101.107.114 08:21, 30 January 2019 (UTC)
Agreed. There is no way that Randall wanted the label for the gray blob to just apply to a couple of layers. It's clearly labeling the entire gray blob as "Google and Amazon". Otherwise, he would have put in another dividing line or two. So all the glue between the layers is being described as "Google and Amazon". Meaning that the layers wouldn't even be able to talk to each other and function correctly without G+A glue between them. Maybe this is "glue" in the technical sense of trivial code which converts from one API to another. The basic point here is that Google lays cable in some places and writes Chrome and owns You Tube, so it's definitely at both ends. I'm not sufficiently knowledgeable to say if it owns/writes stuff in the middle. And I'd be surprised if this was true of Amazon. But it's not my place to comment on the veracity of Randall's remarks, I'm just trying to sort out what he's saying.
That's how I understood it as well. By having there hands in *everything* G+A defeat the whole purpose of having a layered (ie. divided) model, making the 'modern model' just bits and pieces added to G+A code.

Trivia: (Major Spoiler alert) Voldemort originally intended to create six horcruces to divide his soul into 7 (including his own body) pieces. The 6th unintended horcrux is Harry Potter by Voldemort killing his parents. Later on after his revival Voldemort made the snake Nagini to his seemingly 6th horcrux, which was actually his 7th. Does that mean Randall embodies one of the OSI layers from the beginning of his existence? :-) Sebastian --172.68.110.46 08:01, 30 January 2019 (UTC)


Just a point of contention with the current explanation. Right now, Google and Facebook are two of the major players in cloud-based computing: I have seen tutorials on leveraging Google's cloud services to home-brew your own proxy service. As such, a lot of internet services are running ON Google or Amazon, so Google and Amazon DO effectively own, or at least manage, several layers. I do not know if Facebook is one of those, and I would tend to doubt it, considering its size.

Why does the bot have seven layers???

PRESENTATION, SESSION, and NETWORK are not contained within GOOGLE & AMAZON the way the rest of the layers are; there are openings to the outside for those three.

This is true of front facing web pages, but web services exist that may communicate, potentially exclusively, with other services on the same platform. In that case, they would in effect encapsulate all of the layers for that service! This brings up a notable exclusion though, as Microsoft has not been represented here. If you throw them into the mix with Google and Amazon, Thanks to their own Azure cloud services and the ubiquitous Windows and IE/Edge, it would basically only leave argument for the Network layer. Kateract (talk) 15:21, 1 February 2019 (UTC)

I go with Jenga. The three blocks would collapse the tower. The four blocks that don't are because (Randall says) Google and Amazon essentially replace them. Makes sense to me, for those, so I put it in the answer already. PGilm (talk) 21:10, 30 January 2019 (UTC)

Is it worth mentioning that Voldemort (spoilers) only meant to create 6 horcruxes. The idea was to split his soul into seven pieces, with the last piece still residing within his own body. The seventh Horcrux, Harry, was both an accident and his downfall. Thus, Randall may be implying that the top layer (Facebook) might be accidental, and the downfall of Google & Amazon. 141.101.107.216 13:12, 2 February 2019 (UTC) 162.158.18.142 15:32, 5 February 2019 (UTC)

One thing the irregular grey form immediately reminded me of is this: https://goo.gl/images/hNQExG -- I don't know how this early, naive form of encryption should add to the topic at hand, though. Would be happy to find a better reference for those (irregular Scytale?), but all search terms I tried produced way too many results from more advanced forms of encryption.

162.158.18.142 15:32, 5 February 2019 (UTC)

Per "Incomplete" tag, I added the 7 standard OSI layers to the explanation with a simple description of each layer. Further editing may be needed. Ianrbibtitlht (talk) 13:29, 12 June 2019 (UTC)
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