- The Stack We Have
The Internet is built out on stacks not so dissimilar to these. Its eminence and its monotony, both available in excess, are functions of the regularity and resiliency of several specific “ stacks, ” variously abstract models and real technical machines. As its stacks are far more pervasive and powerful than Cybersin and TRON, their dissection demands more reading and interpretation. They are the result of work by well-known scientists and engineers (more on them below), anonymous ingenious workarounds, and coordinated tactical responses of established industrial Users. Equal measures of emergence and equilibrium are at work in the interplay of anticipatory design and realtime problem solving. The shape of The Stack, our accidental megastructure (which contains this Internet but also much more), is also built on some of these models and their particular governing steerage of information networks. The history of Internet stacks also makes clear that the authoring of architectures can produce metasystemic accidents that in turn can themselves counterauthor and redesign the platform in unintended but successful ways.
Consider the lessons of the OSI (open systems interconnection) network model and the TCP/IP network model, on which global Internet connectivity is now largely based. The specification of both standards began in the 1970s, and the latter was more fully adopted by the mid-1980s. For OSI, the network represented has seven discrete layers, from the application layer addressing Users at the “ top ” down to the physical layer (which today may be fiber-optic cable channeling pulses of light). Below the application layer are, in descending sequence, the presentation layer, the session layer, the transport layer, the network layer, the data link layer, and then the physical layer. In simple terms, a message is sent by a user down the stack, layer by layer, until it is transmitted laterally across the physical layer to the receiving node across the street or across the ocean. Upon being received, the message travels back up the stack, from the physical layer to the application layer, and is read by the next user. Each of the layers gathers, specifies, and links heterogeneous technologies together into a functional stratum. <sup>30</sup> On each layer, an instance provides services to and requests service from the layers above and below, and can also pass information laterally to its corresponding layer (i.e., network layer to network layer, as in many so-called level 2 networks linking financial traders and trading centers). Key to the success of this modular model is its flexibility in absorbing future technological innovations that can be introduced at any given layer (e.g., fiber optics instead of copper wire at the physical layer, better router software, an application with better features and security) without disrupting the existing components, so long as the new technology adheres to the protocols established by the platform model that allow it to communicate with its vertically adjacent layers, above and below. In principle any machine could be inserted in a layer of the network if it can adhere to the necessary grammar that would allow it to communicate with its most proximate neighbors. For The Stack, the OSI model serves as a literal and technical prototype for how network architectures operate between very small and large scales and, as the primary abstraction, or universal diagram, for how its heterogeneous participants can arrange communication in a vertical assemblage, now at a megastructural scale.
Platform and Stack, Model and Machine
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