1.1: The long tail
- Page ID
- 113783
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Communication, in general, is about agreement. In order to convey information, two parties have to agree on how they will do the conveying. In conversation, we agree on a common language, for instance. But, should a third party join the conversation, it may be necessary to switch languages to include them. This can be done very quickly (assuming there is a common language between the three). However, for a telecommunications system to function, these agreements need to be in place from the beginning, and any upgrades should take into account previous agreements. Figure \(\PageIndex{1}\) shows a network in which a variety of technologies from different eras are be able to interconnect with each other. As can be seen, a simple landline, maybe even with a rotary dial, must still be able to connect to a modern cellphone. Likewise, internet service must scale from dial up modems through to optical broadband connections, and much more. This does not mean that a network will support a technology in perpetuity, but that the scaling back and removal of support is usually carefully planned well in advance so that users have the time and resources to move to a supported technology.
Within a single network, maintaining support for the long tail of devices can be complicated. However, there is no single world-wide network: every country has its own set of networks, often privately owned. At the same time, interconnection between the different networks is still required. This problem was identified early in the development of digital communications, and, as a result, modern telecommunications provides a hierarchical data structure (SONET/SDH and now OTN) that enables long-tail support.