“Smaller but cleaner.” That’s one of the predictions voiced in I Think We’re All Bozos on This Bus, the 1971 album by comedic legends the Firesign Theatre. “Bozos” describes a dystopian future in which the president of the United States is powered by a mainframe successfully hacked by the hero—cutting-edge technology for the era.

But in fact, the future is smaller but cleaner. Over the past 15 years, big iron has given way to servers powered by inexpensive microprocessors, cloud computing, ubiquitous mobile technology, and a movable feast of wireless networking. The result affords millions of technology users a pervasive presence. When that identity intersects with corporate networks, IT departments must draw on new resources and collaborate with business leaders to ensure everyone on the bus is rolling at peak efficiency toward corporate goals.

Like the PC itself, many of the great disruptions in enterprise IT have come from the bottom—and some chief information officers never saw them coming. Here are some of the tectonic technology shifts that suggest everything we knew in 1998 was wrong.

The rise of the x86 server

At the end of the last millennium, minicomputers and mainframes still had a tenuous toehold on the enterprise. If any smaller computers were going to be important to the enterprise, your average Fortune 500 CIO would have contended, they were going to be servers with processors based on the Reduced Instruction Set Computing (RISC) architecture—not the Complex Instruction Set Computing (CISC) architecture of Intel's x86 family of CPUs. And they would run on a proprietary operating system built on Unix or with a big-iron heritage: Solaris, VMS, HP-UX, AIX, MVS, or OS/390.

Intel? Windows? No way. Linux? What's that?

Sun's Solaris and SPARC architecture boomed along with the dot-com rush of the late 1990s as companies rushed to buy Web servers. But IBM saw the Internet as a guarantee that mainframes would be back in vogue. In 1999, Fortune magazine noted the boom in IBM's CICS mainframe software. IBM marketing Manager Neil McHugh called it "'amusing' that Microsoft's Windows NT operating system gets so much press since it can't handle as many users." The Internet would only make mainframes more useful, they contended—Charles Schwab was using CICS for its stock-trading website, after all.

But the Intel architecture servers that had come in the back door to serve up files over Netware were already well on their way to world domination before Linus Torvalds ever mentioned that phrase. The PC business was beginning to eclipse the old guard in 1998 when Compaq bought Digital Equipment Corp. By the time HP bought Compaq, the Alpha RISC processor was finding itself increasingly squeezed out by racks of cheap Xeons and Opterons. The beachhead that Novell created for x86 servers in the enterprise had been coopted through "co-opetition" by Microsoft. With the introduction of COM+ and then .NET, Windows Server started to gain more enterprise converts as an actual application server. Departments found it cheap and easy to buy their own servers for new projects, bypassing central IT—either with Windows Server or the LAMP (Linux, Apache, MySQL, Perl/Python/PHP) platform. The parts were affordable and easy to scale, as server racks let IT departments acquire precisely the computing power their companies needed.

Virtualization

The success of the x86 server led to a very real problem for many enterprises: "server sprawl." The ease of buying yet another server for yet another app led to a boom in demand for data center real estate—and electricity. Scores of servers sat idle most of the time, but IT was concerned about the stability and security problems that might come with running multiple applications on the same server. Those x86 servers were starting to look more expensive.

Virtualization, which was part of mainframe computing since the 1960s, offered an out. Physical hardware could be split into multiple virtual machines. VMware was founded in 1998 to bring the technology to desktop PCs, and brought virtualization to servers in 2001. It started another disruption in IT when the company released its first full server virtualization platform, VMware Server, in 2006. The open-source Xen virtualization project was grabbed by others, particularly after Citrix acquired the Xen support company XenSource in 2007. Soon after, Microsoft followed with Hyper-V on Windows Server 2008.

The upshot of virtualization for enterprises was that they could keep applications and operating systems separated from each other on the same hardware while consolidating onto fewer physical machines. Virtualization brought mobility. Servers could bounce from machine to machine by being cloned or snap-shotted and "teleported" from one physical box to another. Because of the lowered cost of adding another virtual server rather than a physical one, virtualization created a whole new sort of server sprawl—VM sprawl.

As virtualization spreads chores to machines across the network, pricy, finicky data centers are giving way to virtualized environments that spread the wealth and balance the load. Moving tasks from security to backup to software installation from one location to nodes across the network has made server functions more resilient in times of disaster recovery from black-hat attacks.

Dealing with managing the ballooning numbers of virtual servers at big enterprises such as Amazon led directly to the development of cloud computing. Without the real estate crunch brought on by scaling up to sell everything online (and the growth of virtualization as a result), we could still be sprawling.