TimeSpring has devised a file-based continuous protection product (CPS), called TimeData, for Windows servers. Any and all file changes are instantly written to a networked repository on disk and time-stamped. Restores are via a Windows Explorer-like interface and can be up to the minute.

The company says this gets over the 'protection gap' left between other data protection methods. This gap can be hours or days between backup sessions and hours between snapshots and replication sessions. If a server crashes during such a protection gap then all data added since the last backup, snapshot or replication is lost. With TimeData it's not.

The company says that Recovery Point Objectives can now be to the minute and not hours. Conceptually the process is akin to a continuous series of snapshots. Restores can be of entire databases, folders, files or file contents such as an Excel spreadsheet. Also SQL/Server checkpoints can be identified so that full-integrity database restores can be achieved.

More than one server can be protected by a single TimeData repository. Users on those servers see a "T" drive which represents the TimeData system. They can see their files in different versions as they changed over time.

Agent software on the servers copies file writes across a dedicated Gigabit Ethernet link to the TimeData Repository. This is a standard Windows-based server; TimeData is a software product and runs on any Windows server. To run it you need the Windows server and sufficient disk plus the Gigabit Ethernet link. TimeSpring claimed that the agent software, running on protected Windows-based servers, consumes less than 5 percent of CPU resources.

Unlike Revivio's block-based CPS appliance, the TimeData product is not fault-tolerant and so its integrity could be compromised.

We might consider TimeSpring suitable for NAS and direct-attached servers in less mission-critical applications and Revivio for mission-critical and block-based storage applications.

TimeSpring was founded in 1994 and is based in Newport Beach, California. TimeData is available now and pricing starts at $1,295 per file server - about £800.