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+title = "Interface"
+glassblowers = ["cristobalsciutto.md"]
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+
+Infrastructure accretes in the form of layers of abstractions. Each layer
+builds on top of the prior one, using its metaphors to bootstrap more complex
+ideas. This conceptual leap-frogging permits one to not work from scratch, and
+as such multiply efforts. Critically, however, it becomes imperative to design
+layers of infrastructure that retain an expansive space of possibilities.
+
+Deeper layers of the infrastructural stack evolve at slower paces than higher
+layers, simply because as more infrastructure gets stacked on top, changing too
+quickly may cause the whole edifice to collapse. In other words, the more
+others depend on you, the harder change becomes.
+
+In order to change without affecting those that depend on you, it becomes
+beneficial to define an *interface*, the contract of what you offer. As long as
+the interface is consistent, it does not matter *how* the promise is fulfilled.
+This is the positive side of a black box; you're able to swap it out as long as
+the same things come out, given the same things going in.
+
+If M different users interact with N different providers separately, each of
+the MxN interfaces must be designed. If an intermediate standard is chosen,
+then the M users interact with one standard, as do the N providers. Therefore,
+only M+N interfaces are designed. The standard operates as a narrow waist,
+reducing complexity. The prototypical example of a narrow waist is the Internet
+Protocol (IP). Email, hypertext, domain resolutions, and more all interact via
+the IP, which itself is implemented via copper cable, fibre optic, or radio.
+
+Text and bytes are the two most important narrow waists in computing. The
+computer uses raw bytes as a narrow waist between a variety of media (images,
+text, video, 3D models, etc) and a variety of transmission and compression
+techniques. An HTTP message transmits arbitrary data in the form of text or
+bytes between a client and server. It does not matter what is in the payload.
+Similarly, gzip can be used to encode any arbitrary sequence of bytes,
+regardless if the file is a sequence of text or the RGB of an image.
+
+Ref: ![](bib:7817cc0f-a538-4c1d-872e-b2bbb874c094)
+Ref: https://www.oilshell.org/blog/2022/02/diagrams.html 
+Ref: https://www.ietf.org/rfc/rfc791.txt
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