With the caveat that history is not always destiny, Cisco’s first quarter financial results set off alarm bells, less because of the quarterly results and more because of the weak forecast going forward.

Cisco revenue rose 1.8 percent in its first fiscal quarter and earnings grew, compared with its projection of three percent to five percent growth.

Cisco also forecast a revenue decline of eight percent to 10 percent in the current period.

For some, the worrisome statement by John Chambers, Cisco CEO, was that the sharp sales slowdown in quarterly orders, particularly in Brazil, Russia, Mexico, India and China, was something had "never seen" before.

Orders for all emerging markets declined 21 percent. One suspects other suppliers of technology to telecom and cable TV companies likewise are going to report quarterly weakness as well.

Those cyclical trends might also reinforce thinking about one long term structural trend, namely the historic pattern of technology leadership in the computing industry.

Since the advent of the mainframe era, no firm dominant in one era has survived to lead the next era. That is not to say it cannot be done, only that it never has been done before. Still, at the moment, it does not appear that firms including Microsoft and Cisco will manage to retain the leadership they once had in the coming era of computing.

What remains unclear, though, is what we eventually will wind up calling the coming era. There is not yet consensus on what to call the current era, which superseded the “PC era,” or the client-server computing era.

Most might agree that use of the Internet, by a wide range of appliances, is characteristic of the present era. So perhaps we might call the present era the “Internet computing” era. But there is not yet complete agreement.

Even murkier is what we will call the era we will enter next,  a period many would say will be characterized by cloud computing, mobile devices, pervasive computing, an Internet of Things or machine-to-machine services. All of those facets make sense.

But we still don’t know what will emerge as the defining characteristic of the next era. There is one data point that never fits completely neatly in the taxonomy of computing eras, though. And that is Apple.

Apple never “led” the PC era, though it has become newly influential in the “Internet era.” Whether that means Apple could break the mold is a question a reasonable person might ask.

But Google breaks the mold as well. In the past, era leaders have supplied core computing hardware and software. Google arguably does that as well, with one unusual and unprecedented difference: it is the first era-defining computing technology firm ever to have a business model based on advertising, not sales of hardware and software.

For some of us with a historian’s bent, that bears watching. Apple and Google might be two firms that somehow manage to escape, or manage to redefine, the historic pattern of computing industry leadership.