Different types of road warriors have different needs for backing up critical data on notebooks and other devices, such as PDAs (personal digital assistants). Corporate executives who regularly come and go from the CO (central office) can be dubbed intermittent warriors. Other workers who are gone for longer periods can be called intermediate warriors. Still others may permanently reside in remote locations and can be categorized as continuous warriors.

Although intermittent, intermediate and continuous warriors have different needs, they all share the same basic preferences in a backup solution: fast and easy. If a deployed solution isn't both, your user may neglect to back up, and may lose critical data when disaster strikes. Several backup strategies can meet the various demands of different types of warriors. No one solution excludes the others. Enterprises can supply warriors with removable storage devices, provide access to external hard disks, synchronize data between notebooks and file servers, and schedule incremental backups.

Removable Storage

Plug-and-play devices with bundled software make removable storage products a viable solution for all road warriors. Notebooks with compact discs can back up critical data at speeds of 1,500 KBps (CD-Rewritable or CD-RW) to 1,800 KBps (CD-Recordable or CD-R) and, with software like Roxio's Easy CD Creator or Toast, warriors can press from 550 MB to 650 MB of data easily during a coffee break. Also, Iomega Corp.'s 100-MB and 250-MB Zip disk storage solutions are affordable and easy to use with laptops through a parallel or USB port capable of 1.4 MBps and 900 KBps data transfer, respectively.

If removable storage weighs your warriors down, they can copy data to a JMTek Flash USBDrive at 500 KBps or an Iomega Microdrive at 5.2 MBps. Either solution can put gigabytes of data in a pocket or purse. With Iomega QuikSync 3.0 software, warriors can synchronize critical files to removable, network or local drives. If you prefer to back up files rather than synchronize them, Dantz Development Corp.'s Retrospect Backup software supports almost any storage device including tape, SuperDisk (LS-120), CD-R/RW and DVD.

External Hard Disks

One way to provide centralized backup for remote users is to make external disks available through a central file store for warriors to copy and store critical data. Simply expanding the available disk space in a message store or providing a central file server on a corporate LAN accessible through a VPN (virtual private network) can do the job. Then, back up the message store or file server to tape on a regular basis. Remote users can mail themselves critical data or drag and drop files from their notebooks to the shared storage areas.

Adding external disks may be an easy solution for those who work with only a subset of their files while on the road. It is too slow, however, for continuous warriors who never come home and work on data lines ranging from 28.8 Kbps to 56 Kbps. For these warriors, dragging and dropping files can be time-consuming, turning a mission-critical remote-access solution into a bottleneck. Upgrading their connections to broadband using a DSL (digital subscriber line) or cable-modem service can bring their data closer to home and reduce the costs associated with a remote-backup solution. In addition, off-the-shelf backup solutions include technologies made for remote users.

Some solutions back up an initial set of critical data and thereafter only back up and transmit the delta changes to those files that occur over time. Delta transfers transmit the changes or modifications made to files, not whole files, thus reducing the time required to back up. This can be done by synchronizing local files with files stored on the network, or backing up only those local files that have been modified since the last backup, and sending only the changes over the network in compressed format.

Synchronized Backup

Synchronizing local files with remote files is not new. Microsoft's MS Briefcase synchronized local files with network files long ago. And products such as Traveling Software's LapLink and Symantec Corp.'s pcAnywhere added compression and delta-transfer technologies to facilitate synchronization and backup. Today, Microsoft Windows ME and 2000 include a Synchronization Manager, and a number of products, such as Iomega's QuikSync and LapLink's PCsync, are capable of synchronizing local files across devices or networks. To see how well synchronization technology stacks up as a backup solution, I looked at Mobiliti's Network/Unplugged 3.0a in our Syracuse University Real-World Labs®.

Network/Unplugged (N/U) provides a networked backup and synchronization solution for Windows 95, 98, NT 4.0 and 2000 clients. Its Synchronization Server acts as a conduit through which N/U clients use delta transfer technology to synchronize local files with network files residing on back-end file servers (see "Synchronization Backup Solution"). N/U's iDESP (Intelligent Delta Selection Process) technology transmits only the changes made to files and not whole files.

N/U's Synchronization Server runs as a service under Windows NT 4.0 and 2000 server. After installation, the Synchronization Server (4,032 KB of RAM) and agent (3,520 KB of RAM) load automatically to use a service account (MNUSYNCServer&) that provides synchronization and file transfers on behalf of clients. The service account does not belong to any group and does not require any special permission other than "change" (read, write, execute, delete) access to a temporary folder on the Synchronization Server (for more on N/U and synchronization, see "Mobiliti's N/U Backup Plan").

N/U supports back-end file servers running Microsoft Windows NT 4.0/ 2000, Novell NetWare, Sun Solaris and Linux, and can synchronize over IPX/SPX, TCP/IP and NetBEUI protocols. Clients can access the server and synchronize files over network, RAS (Remote Access Service), VPN and wireless connections.

Connected TLM's Web-based administrative console (screen view) Click here to enlarge

N/U client agents used 45 KB of memory on my IBM 600E ThinkPad. With N/U's Project Manager, I set 30 files (17 MB) to synchronize with the Synchronization Server. Over a RAS connection (31,200 Kbps), the initial backup took 23 minutes; over a 100-Mbps LAN, it took only 30 seconds. Although subsequent synchronizations took only minutes and seconds over RAS and LAN, the initial backup would be onerous for continuous warriors on slow data lines. Intermittent and intermediate warriors, however, can initialize the backup in the CO and synchronize on the road, as only the delta changes are transmitted.

N/U comes with an integrated deployment kit for system administrators to configure and customize an enterprise rollout. The kit supports silent installs and locked configurations for warriors who require little or no user interaction.