job, Ramleth started a company inside Bechtel called Genuity, which was an early ISP and hosting company. Genuity was later sold to GTE.

Steve Bourne is CTO at El Dorado Ventures, where he helps assess ven-ture-capital investment opportunities. Prior to El Dorado, Bourne worked in software engineering management at Cisco, Sun, DEC, and Silicon Graphics. He is a past president of ACM and chairs both the ACM Professions Board and the ACM Queue Editorial Board.

moderator

Mache Creeger is principal of Emergent Technology Associates, where he provides marketing and business development enterprise infrastructure consulting for large and small technology companies. Beginning his career as a research computer scientist, Creeger has held marketing and business development roles at MIPS, Sun, Sony, and InstallShield, as well as various start-ups. He is an ACM columnist and moderator and head wrangler of the ACM CTO Roundtable series.

 

cReeGeR: Let’s begin the discussion with a general question and then dig down into some of the deeper issues. How would you define cloud computing?

TucKeR: Cloud computing is not so much a definition of a single term as a trend in service delivery taking place today. It’s the movement of application services onto the Internet and the increased use of the Internet to access a wide variety of services traditionally originating from within a company’s data center.

BADRos: There are two parts to it. The first is about just getting the computation cycles outside of your walled garden and being able to avoid building data centers on your premises.

But there’s a second aspect that is equally important. It is about the data being in the cloud and about the people living their lives up there in a way that facilitates both easy information exchange and easy data analysis.

The great search tools available today are a direct result of easy access to data because the Web is already in the cloud. As more and more user data is stored in the cloud, there is a huge opportunity that transcends just computation being off-premises because there

Le W TucKeR
cloud computing
is not so much a
definition of a single
term as a trend in
service delivery.
It’s the movement
of application
services onto the
Internet and the
increased use
of the Internet
to access a
variety of services
traditionally
originating from
within a company’s
data center.

is a relatively high-bandwidth connection to all those bits.

TucKeR: Tim O’Reilly’s definition of Web 2.0 was that the value of data significantly increases when a larger community of people contributes. Greg [Badros]’s characterization complements that nicely.

VoGeLs: It’s not just data. I also believe that clouds are a platform for general computation and/or services. While telcos are moving their platforms into clouds for cost-effectiveness, they also see opportunities to become a public garden platform. In this scenario, people can run services that either extend the telco’s services or operate independently. If, for example, you want to build an application that has click-to-call or a new set of algorithms such as noise detection in conference calls, then you can run those services connecting to the telco’s platform. The key is having execution access to a common platform.

Because we have a shared platform, we can do lots of new things with data, but I believe we can do new things with services as well.

TucKeR: I see it as three layers: SaaS (software-as-a-service), which delivers applications such as Google Apps and Salesforce.com; PaaS ( platform-as-a-service), which provides foundational elements for developing new applications; and IaaS ( infrastructure-as-a-service), which is what Amazon has led with, showing that infrastructure can also be accessed through the cloud. I believe it is in this infrastructure layer—in which we’ve virtualized the base components of compute and storage, delivering them over the Internet— where we have seen the fundamental breakthrough over the past two years.

VoGeLs: Understanding cloud computing requires a look at its precursors, such as SaaS before it became this plat-form-like environment; SOA ( service-oriented architecture); virtualization (not just CPU virtualization but virtualization in general); and massively scalable distributed computing.

These were technologies that we needed to understand fully before cloud computing became viable. We needed to be able to provide these services at scale, in a reliable manner, in a way that only academics thought about 10 years ago. Building on this foundation, we