The OSI model idea structurally separates seven functions, with "application" at layer seven and physical layer at layer one. That should strike you as describing the relationship between "over the top" applications of every sort and the network used to deliver the app.
As applied to any business using a software-heavy product, that means there can be a separation of facilities, entities using facilities to create "communication" or "content" services, and application creators. The form will follow the function, you might say.
For software developers, service providers and consumers and users, the advantages of using the OSI model are numerous. OSI Model
Features and apps can be created or changed without requiring modification of other parts of the complete communications "stack." In other words, a user can switch from one supplier of a word processing or instant messaging app to another without "changing networks."
If a user wants to switch from Microsoft Office to Google Docs, that doesn't mean a PC or network access provider also has to be changed.
A user can switch from one device to another without disrupting use of desired apps. Twitter should work on any brand of smart phone, or any brand of tablet or PC.
At one level, everybody in the ecosystem wins. Because there is a compartmentalization of functions, changing one app for another, or a wireless network for a fixed network connection, should not disrupt use of an application.
It's harder in practice than it is in theory. It still isn't easy to start a session of some type on a single device, then seamlessly transition to a different network and another device, without disrupting the session.
Some of you will quip here that it isn't always easy to sustain a single session, on a single network, using a single device, either. That's also true, but is not a defect of OSI!
However, in principle, and over time, in practice, a user should be able to start a session of some sort (voice or video or Web app) and then maintain the session even when switching from one network to another, from fixed to mobile, for example.
But there also are clear business implications. Though in the past networks got built to support one major application, these days networks are simply built to support any type of application, whether that is voice, video, Web sessions, text, documents, photos, music or any other types of digital information.
These days, it is technologically possible, and increasingly will be possible in business terms, to deliver anything, to anybody, on any device, in fairly elegant way at times, in reasonable ways at other times. That has serious business implications.
It means that firms "not in my business" can get into your business. Competitors increasingly do not need to "own and control" all the assets used at every level of the OSI software stack, including the physical layer assets.
By the same token, think of collaboration using voice, messaging and web assets as an application. Webex is one example, but so are phone calls. A layer seven app can be run over any compliant network. You might note that bandwidth on every network is not yet consistently sufficient to support a collaboration app in such a way. That is true, but also changing. It won't be a problem much longer.
And whether it is yet widely understood, or not, sooner or later app providers whose major products include entertainment video, voice, hosted PBX, videoconferencing and messaging will want to deliver those applications over the top. That also has implications.
In the legacy world, physical layer access was a matter of geography. A supplier needed permission from a government authority to operate a network, to support an application. Cable operators needed municipal permission to build a network to sell television. Telcos needed certificates of convenience and necessity.
Cloud computing and OSI, plus widespread and universal broadband, changes much of that older model. A company that might also be a telco or cable company or ISP, might or might not "own" physical assets when creating and then delivering applications.
A product of the Open Systems Interconnection effort at the International Organization for Standardization, the OSI model is a way of allowing developers to create software in an abstracted way, without having to know all the details of other parts of how a particular network works.
It also is an analogy for the way the communications and entertainment business already is starting to change. "Over the top" is not just something "other companies" do. It is something layer one asset owners also are starting to do. The only question, over time, is when over the top gets embraced more widely as "my" business strategy, not just "the other guy's strategy."
