Long before the internet, there was a simplier time when the typical mode of communication was a telephone. These early communication devices were based on the idea of circuit switching, where a dedicated circuit is tied up for the duration of the call and communication is only possible with the single party on the other end of the circuit. In the 1970's a major shift occurred, this shift was the move from circuit switching to a newer packet switching methods. With packet switching, a system could use one communication link to communicate with more than one machine by disassembling data into datagraphs, then gather these as packets. Not only could the link be shared (much as a single post box can be used to post letters to different destinations), but each packet could be routed independently of other packets. This was a revolutionary advancement and lead directly to a US military project called ARPAnet.
ARPAnet which stands for Advanced Research Projects Agency Network and is widely considered the first packet switching network and a direct predessor to today's Internet and what I consider the first compute cloud.
What's interesting about ARPAnet and today's move toward cloud computing is that they both shared similar ideals and goals.
- Both are designed to work unambiguously with a broad range of computer architectures
- Both are designed were to designed to be multi-tenant
- Both are designed to be global and distributed across geographically disperse environments.
- Both are application agnostic, meaning they could support a wide variety of applications from voice to data.
- Both are designed withstand losses of large portions of the underlying networks. ARPANET was designed to survive network losses, but the main reason was actually that the switching nodes and network links were not highly reliable, similar today internet;
I'll keep you posted as continue to write my cloud computing guide. If you're interested in contributing, please get in touch.
* 1 Abbate, Inventing the Internet, pp. 8
* 2 Norberg, O'Neill, Transforming Computer Technology, pp. 166
* 3 Hafner, Where Wizards Stay Up Late, pp. 69, 77
* 4 A History of the ARPANET, Chapter III, pg.132, Section 2.3.4
A few people have pointed out that ARPAnet wasn't global. I'll look into it.