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DVD MEDIA ARE HOT !
DVD recordable and rewritable media are hot ! This week the 2 billionth (2.000.000.000) DVD R(W) (or /RAM) disc will be sold somewhere in the world. It took the industry around 6 years to get to this 2B mark. In the coming year, however, it is expected that another 1.5 Billion media will be sold !

Naturally, a lot of companies are gearing up their production lines to be able to get a piece of this huge market. Beside the first tier media manufacturers like Ritek, CMC, Ricoh, Mitsubishi Chemical, Infodisc, Optodisc, etc. and lesser known brands like Princo, Skymedia, etc. a lot of unknown, mostly Asian or Eastern European media are expected to hit the market. The origins and quality of these media is often unknown.

MID CODES
All the major manufacturers use socalled Manufacturer ID (MID) codes, which are like digital signatures imprinted into the media, which make it possible to trace the origin of the disc and the characteristics of the recordable/rewritable layer.

Because of the different characteristics, each type of media requires a different approach when burning data. Especially the laser power is important: too much power may destroy the recordable/rewritable layer, but too little power may result in unreadable data as well.

FIRMWARES AND MEDIA COMPATIBILITY
In order to make sure that a DVD RW drive works well with a certain media, it is important for every drive manufacturer to tune the firmware of their drive to each type of media. As soon as the media is inserted into the drive, the MID code is read and according to a MID code list in the firmware, the drive knows exactly what burning characteristics (laser power, etc.) should be used with this particular media. Because of the current wave of new media from all major manufacturers, new MID codes are released almost weekly, forcing the drive manufacturers to update their firmwares regularly.

BEWARE OF CHEAP MEDIA
The problem with most media is that, unless you buy media from a wellknown brand name such as TDK, Verbatim, Panasonic, etc. you can't really tell what you bought until you've tried it on your DVD RW drive.

Many unknown companies (mostly small Asian or Eastern European) who are in the business of producing media only for the easy money, take advantage of this fact by luring customers into buying their media by offering extremely low prices. Because the MID code can also be used to trace media back to the manufacturer, they often don't use any MID code and rumor has it that some companies even "steal" MID codes from other manufacturers, making it look like the discs are made by reliable companies.

The 1st problem with this type of media is that the quality may be unreliable, though this is not necessarily the case.

The 2nd problem is that your drive may be incompatible with this media, at least until the drive manufacturer has become aware of the existence and characteristics of those media and has gone through the trouble of locating, purchasing and tuning a new firmware.

Most drive manufacturers keep close contact with all the wellknown media manufacturers to make sure their drives can support all the media that are manufactured by them.

It's an almost impossible job to keep track of all these small media companies, however, who in some cases don't even want to be found in the first place ! In these cases, if a drive manufacturer wants to support these media, the response will have to come from the endusers who buy these media and alert the drive manufacturer about the existence of those media.


Marco
BTC Europe Support