Bell’s Law accounts for the formation, evolution, and death of computer classes based on logic technology evolution beginning with the invention of the computer and the computer industry in the first-generation, vac-uum-tube computers (1950–1960), second-generation, transistor computers (1958–1970), through the invention and evolution of the third-generation Transistor-Transistor Logic (TTL) and Emitter-coupled Logic (ECL) bipolar integrated circuits (ICs) from 1965–1985. The fourth-generation MOS and CMOS ICs enabling the microprocessor (1971) represents a “break point” in the theory because it eliminated the other early, more slowly evolving technologies. Moore’s Law [ 6] is an observation about integrated circuit semiconductor process improvements or evolution since the first IC chips, and in 2007 Moore extended the predic-

one as a wireless sensor network class. Field Programmable Logic Array chips with tens to hundreds of millions of cells exist as truly universal devices for building nearly anything.

tion for 10– 15 more years, as expressed in Equation 1. The evolutionary characteristics of disks, networks, displays, user interface technologies, and programming environments will not be discussed here. However, for classes to form and evolve, all technologies must evolve in scale, size, and performance at their own—but comparable—rates [ 5].

In the first period, the mainframe, followed by minimal computers, smaller mainframes, supercomputers, and minicomputers established themselves as classes in the first and second generations and evolved with the third-generation integrated circuits circa 1965–1990. In the second or current period, with the fourth generation, marked by the single processor-on-a-chip, evolving large-scale integrated circuits (1971–present) CMOS became the single, determinant technology for establishing all computer classes. By 2010, scalable CMOS microprocessors combined into powerful, multiple processor clusters of up to one million independent computing streams are likely. Beginning in the mid-1980s, scalable systems have eliminated and replaced the previously established, more slowly evolving classes of the first period that used interconnected bipolar and ECL ICs. Simultaneously smaller, CMOS system-on-a-chip computer evolution has enabled low-cost, small form factor (SFF) or cell-phone-sized devices (CFSD); PDA, cell phone, personal audio (and video) devices (PADs), GPS, and camera convergence into a single platform will become the worldwide personal computer, circa 2010. Dust-sized chips with relatively small numbers of transistors enable the creation of ubiquitous, radio networked, implantable, sensing platforms to be part of everything and every-

BELL’S LAW

A computer class is a set of computers in a particular price range defined by: a programming environment such as Linux or Windows to support a variety of applications; a network; and user interface for communication with other information processing systems and people. A class establishes a horizontally structured industry composed of hardware components through operating systems, languages, application programs and unique content including databases, games, images, songs, and videos that serves a market through various distribution channels.

The universal nature of stored-program computers is such that a computer may be programmed to

replicate function from another class. Hence, over time, one class may subsume or kill off another class. Computers are generally created for one or more basic information processing functions—storage, computation, communication, or control. Market demand for a class and among all classes is fairly elastic. In 2010, the number of units sold in classes will vary from tens for computers costing around $100 million to billions for SFF devices such as cell phones selling for under $100. Costs will decline by increasing volume through manufacturing learning curves (doubling the total number of units produced results in cost reduction of 10%–15%). Finally, computing resources including processing, memory, and network are fungible and can be traded off at various levels of a computing hierarchy (for example, data can be held personally or provided globally and held on the Web).

The class creation, evolution, and dissolution process can be seen in the three design styles and price trajectories and one resulting performance trajectory that threatens higher-priced classes: an established class tends to be re-implemented to maintain its price, providing increasing performance; minis or minimal-cost computer designs are created by using the technology improvements to create smaller computers used in more special ways; supercomputer design (the largest computers at a given time come into existence by competing and pushing technology to the limit to meet the unending demand for capability); and the inherent increases in performance at every class, including constant price, threaten and often subsume higher-priced classes.

All of the classes taken together that form the com-