- SecurDisc technology will be a must-have for some businesses
- Security features inevitably make this drive harder to use
- The data reliability feature always increases write times to the maximum
- OS support is Windows only
LG’s GSA-H55N DVD rewriter features SecurDisc technology that provides data protection and authentication through a combination of drive hardware and software encryption. The GSA-H55N is described as a ‘Super Multi’ drive because, in the manufacturer's words, it is 'all DVD and CD formats compatible', including dual-layer DVD.
The GSA-H55N has a maximum write speed of 20x for DVD+R and –R media; write and read speeds for other media vary up to maximum of 48x for CD-R. All of these features, and particularly the SecureDisc encryption and authentication, make it an attractive choice for business use.
The GSA-H55N is one of the new breed of drives that retains the ‘half-height’ standard for height and width, but has a reduced depth of only 165mm compared to about 190mm for earlier designs. This is an E-IDE/ATAPI device and it has the (by now very familiar) array of 2-pin and 4-pin audio connectors, 3-way drive select, 40-pin E-IDE ribbon connector and 4-pin AMP power connector . As packed, the GSA-H55N is supplied with a matte black bezel, but you also get a replacement light mushroom bezel, with fitting instructions, in the box. Four drive mounting screws are also provided.
The software CD provided with the drive provides copies of Nero Express writing software with SecurDisc support, Nero InCD UDF packet-writing and SecurDisc reading software, Cyberlink PowerProducer DVD video authoring software and Cyberlink Power DVD movie playback software. The autorun install offers a choice of installing all of these applications or just the Nero programs. A reboot is required following the install.
We actually reviewed the GSA-H55L model, which supports LightScribe labelling. This uses the same drive head that writes the data to laser-expose a photosensitive layer on the label side of specialised discs. Although this seems good in theory, in practice it’s currently limited to monochrome, produces low-contrast labels, requires specialised media and can take up to 36 minutes to write at the highest resolution. In comparison, the old full-colour sticky label seems a lot more attractive and practical.
We have been unable to find a UK price for the GSA-H55L, and feel that users should be just as happy with the otherwise identical GSA-H55N drive, which lacks the LightScribe feature.
SecurDisc data protection
LG has an exclusive licence until the end of September 2007 for SecurDisc technology with its developers Ahead Software (Nero) and HL Data Storage. SecurDisc claims the following advantages:
- Data Reliability to save your data if a disc is damaged;
- Password Protection to prevent unwanted access to your data;
- Data Integrity Check to preserve your data over time;
- Digital Signature to verify the authenticity of your files; and
- Copy Protection to stop unwanted copying of PDF documents.
The Data Reliability feature relies on the premise that recordable CDs and DVDs are rarely filled to anywhere near capacity, so the remaining empty space on the media can be used for additional redundant code derived from the information selected for writing to the disc. If the disc is damaged, this redundant code can be used to try and reconstruct the missing data.
Providing good-quality media are used and discs are handled with care (that is, fingerprints, dirt and scratches are avoided and discs are properly stored), then the redundancy and checksum coding already used for standard CD and DVD is quite robust and data loss is most unusual. However, many users treat CDs and DVDs as if they are indestructable, which they are not. SecurDisc's Data Reliability feature acknowledges these bad habits and puts yet another layer of redundancy on top of what’s already there, so sloppy users can continue treating their media badly. Of course, even this extra redundancy does not guarantee that data can be recovered from a damaged disc.
A drawback of the Data Reliability feature is that apparently it cannot be turned off, and will always fill all empty space with redundancy data. This means that archiving or copying relatively small amounts of data can take much longer as the extra redundancy code is created and written to the disc. Presumably it's also the case that large volumes of data are not as well protected by this system because less free space is available to store the extra redundancy data.
SecurDisc allows data written to the drive to be encrypted using the AES 128-bit algorithm. The user supplies a password when the data is written to a disc; this password must then be entered to decrypt and read the data. The current Nero software insists that the password must be at least 16 characters in length. It also has a password strength indicator divided into 'weak', 'medium' and 'strong'. According to this gauge, a strong password must be many hundreds of characters in length. This illustates the major weakness of password systems, because strong passwords are certainly not likely to be easily memorised or easy to enter. Therefore it’s likely that any strong password chosen will be stored as a possibly vulnerable file and simply cut and pasted. Authentication of data written with SecurDisc is also provided by private/public key pair digital signature.
The Data Integrity feature is intended to provide advanced warning of data corruption due to disc damage. It checks for errors between the redundant copies of the data and generates a warning message if these are at critical levels. At this point the data should still be retrievable and may be copied to a fresh disc.
SecurDisc allows files to be copy protected so they can only be read from the original disc and these files cannot be copied to another drive. At present this facility is only available for PDFs and once protected these files can only be read on a drive with SecurDisc hardware support.
SecurDisc-protected media can be read in a non-SecurDisc drive, by installing and using Nero InCD Reader 5.5. When a SecurDisc is inserted in a non-SecurDisc drive, an autorun program checks for SecurDisc hardware support. If this is absent, the autorun program displays a message linking to the InCD download web page. This only applies to non-copy-protected discs. TO read a copy-protected (PDF-only) SecurDisc, a SecurDisc-compatible drive is required.
Software tools and updates to use SecurDisc can be downloaded from the SecurDisc web site. These include the SecurDisc Viewer for reading files, version 5 of InCD Reader and a full update of Nero 7 with SecurDisc support.
The LG GSA-H55N is obviously aimed at the business market, where current CD or DVD recordings represent a security weakness. As ever with improved security, there’s an associated decrease in convenience and ease of use. However, businesses with concerns over the security of recordable CD and DVD media should find the trade-off worthwhile
The PDF copy-protection feature would be a great way to publish text and pictures if only if worked on all drives and wasn’t limited to devices with SecurDisc support.
The SecurDisc system also offers increased resistance to data loss due to disc mishandling and damage. However, if you don’t require the password protection and digital authentication features, you're probably better off ensuring that you look after your CD/DVD media and using standard drives.