Handbook of Information Security Management:Physical Security

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Implementing an encryption strategy doesn’t need to be too costly or restrictive. If the primary objective is protection of data during remote transmission, then a strategy mandating encryption of the file before it is transmitted should be put in place. If the objective is to protect the file at all times when it is in a remote environment, file encryption may be considered, though its use may be seen as a burden by users, both because of the processing overhead and the potentially extra manual effort of performing the encryption and decryption for each access. (With some encryption schemes, users may have to decrypt the file before using it and encrypt it again before storing it on the portable computer. More sophisticated applications provide automatic file encryption and decryption, making this step nearly transparent to the user.) Portable computer hardware is also available that can provide complete encryption of all data and processes on a portable computer. The encryption technology is built into the system itself, though this adds to the expense of each unit.

A final point needs to be made on implementing encryption for portable users, and that is the issue of key management. Key management is the coordination of the encryption keys used by users. A site key management scheme must be established and followed to control the distribution and use of the encryption keys.

VIRUS PROTECTION IN A PORTABLE ENVIRONMENT

All portable or off-site computers targeted to process company data must have some consistent form of virus protection. This is a very important consideration when negotiating a site license for virus software. What should be negotiated is not a site license per se, but rather a use license for company’s users, wherever they may process company data. The license should include employees’ home computers and as well as company-owned portables. If this concept isn’t acceptable to a virus software vendor, then procedures must be established in which all data that have left the company and may have been processed on a nonvirus-protected computer must be scanned before it can reenter the company’s internal computing environment. This can be facilitated by issuing special color-coded diskettes for storing data that are used on portables or users’ home computers. By providing the portable computer users with these disks for storage and transfer of their data and mandating the scanning of these disks and data on a regular basis on-site, the threat of externally contracted computer viruses can be greatly reduced.

CONTROLLING DATA DISSEMINATION

Accumulation of data on portable computers creates the potential for its disclosure. This is easily addressed by implementing a variety of procedures intended to provide checks against this accumulation of data on shared portable computers. A user procedure should be mandated to remove and delete all data files from the hard disk of the portable computer before returning it to the company loan pool. The hardware loaning organization should also be required to check disk contents for user files before reissuing the system.

THEFT PROTECTION

The threat of surreptitious theft can be in the form of illicit copying of files from a user’s computer when unattended, such as checked baggage or when left in a hotel room. The simplest method is to never store data on the hard disk and to secure the data on physically secured diskettes. In the case of hotel room storage, it is common for hotels to provide in-room safes, which can easily secure a supply of diskettes (though take care they aren’t forgotten when checking out).

Another method is to never leave the portable in an operational mode when unattended. The batteries and power supply can be removed and locked up separately so that the system itself is not functional and thus information stored on the hard disk is protected from theft. (The battery or power cord could also easily fit in the room safe.) These measures can help protect against the loss of data, which might go unnoticed. (In the event of outright physical theft, the owner can at least institute recovery procedures.) To protect against physical theft, something as simple as a cable ski lock on the unit can be an effective protection mechanism.

USER EDUCATION

The selection of portable computing protection strategies must be clearly communicated to portable computer users by means of a thorough user education process. Education should be mandatory and recurring to assure the most current procedures, tools, and information are provided to portable users. In the area of remote access to on-site company resources, such contact should be initiated when remote users register in the remote access authentication system.

For the use of shared company portable computers, this should be incorporated with the computer check-out process; portable computer use procedures can be distributed when systems are checked out and agreed to by prospective users. With respect to the use of noncompany computers in a portable mode, the best method of accountability is a general user notice that security guidelines apply to this mode of computing. This notification could be referenced in an employee nondisclosure agreement, in which employees are notified of their responsibility to protect company data, on-site or off-site. In addition to registering all portable users, there should be a process to revalidate users in order to maintain their authorized use of portable computing resources on a regular basis. The registration process and procedures should be part of overall user education on the risks of portable computing, protection mechanisms, and user responsibilities for supporting these procedures.

Exhibit 3 provides a sample checklist that should be distributed to all registered users of portables. It should be attached to all of the company’s portable computers as a reminder to users of their responsibilities. This sample policy statement includes nearly all the protection mechanisms addressed here, though the company’s specific policy may not be as comprehensive depending on the nature of the data or access method used.


Exhibit 3.  Portable Computing Security Checklist

SUMMARY

The use of portable computing presents very specific data security threats. For every potential threat, some countermeasure should be implemented to ensure the company’s proprietary information is protected. This involves identifying the potential threats and implementing the level of protection needed to minimize these threats. By providing a reasonably secure portable computing environment, users can enjoy the benefits of portable computing and the organization can remain competitive in the commercial marketplace.


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