San Francisco startup Piston is putting the cloud on a memory stick. Beginning next week, it will offer developers a USB device or "cloud key" with OpenStack cloud software preloaded onto it. Also included is Piston's enterprise operating system for the cloud, PentOS.

To configure rack-mount servers for a cloud, the enterprise cloud manager will plug the cloud key into his PC or laptop and set parameters in configuration files for the types of cloud servers that he wants, a task he can do outside the data center. Inside the data center, an authorized administrator can then plug the device into the network switch at the top of a server rack. The software on the device automatically loads into the switch, where PentOS discovers the servers in the rack and configures them into a cloud system in a "hands-free" implementation.

Piston is focused on "taking the complexity of configuring cloud services out of the hardware and putting it into software," said Joshua McKenty, co-founder and CEO of Piston, a San Francisco startup that announced its launch with $4.5 million in funding from Hummer Winblad and True Ventures in July.

[See what Piston execs said as they first emerged from stealth mode. Read Startup, Piston, Eyes Private Cloud Security. ]

In addition, PentOS is meant to leverage OpenStack's ability to use the on-premises, enterprise Active Directory Server to authenticate administrators for the enterprise cloud. It won't allow an IT staffer with administrative privileges to log in and take over the cloud servers on a local basis, the way a consultant or knowledgeable IT staffer with administrator privileges might do in other circumstances, McKenty said. Rather, each administrator must use a centralized login process that can be monitored by IT managers more easily and where (hopefully) the wrong party would be more easily spotted and halted.

PentOS itself is based on a trimmed-down version of Linux, one that is geared to do only the functions necessary for the cloud operating system. With all other modules dispensed with, the operating system has a reduced attack surface, he said.

Using OpenStack, the PentOS operating system is able to provision and track virtual machines, assign networking and storage as well as CPU and memory, and supply high availability through automated failover of virtual servers. The system maintains distributed backup copies of data so that a server loss will not result in a long-term outage.

In addition, McKenty said it supplies one of the first implementations of CloudAudit, a draft standard of the Internet Engineering Task Force (IETF) determining how a cloud configuration may be designated as meeting HIPAA, FISMA, PCI, or other regulatory and compliance standards.

McKenty, a veteran of NASA's Nebula cloud project, said he serves on the working group of the IETF that drafted the CloudAudit standard. By creating an infrastructure that meets the standard, events in the cloud become auditable and able to meet the compliance requirements, he said. The draft of the 1.0 standard was released in July 2010 for public comment.

The first version of PentOS will be made available only to developers attending the OpenStack Summit next week in Boston. It will become generally available at the end of November. McKenty said the enhancements that make PentOS easy to install and implement are its proprietary code, but the general functionality of CloudAudit will be added to OpenStack as Piston donates the code to the project in the near future.

No pricing on PentOS has been set, with McKenty claiming only that it will be priced comparable to competing private cloud software products. Competitors include Eucalyptus Systems, which produces a software stack compatible with Amazon Web Service's APIs; Nimbula, with Amazon-experienced architects producing a more general purpose cloud; Cloud.com, another implementer of the OpenStack suite; and Nebula, a startup that includes NASA CTO Chris Kemp, offering an OpenStack-based appliance.

Piston has 17 employees, four more than at last report. Its co-founder is Christopher McGowan, now CTO, and former technical lead at virtual server hosting firm Slicehost, acquired by Rackspace in 2008. Rackspace and the NASA Nebula cloud team co-founded the OpenStack open source code project last July. Over 100 companies now participate in it.