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ASUS CD-R/RW Drive User’s Manual
VI. APPENDIX
VI.
Appnedix
Glossar
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What is Multisession CD?
The principal purpose of multiple sessions is to allow additional data to be appended
to a previously recorded disc.
NOTE: Some older cd readers can read only the first session of a multisession disc.
A session is defined as an area including lead-in, program data and lead-out.
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A CD-R recorder that supports multisession recording can write a disc that
will have multiple sessions linked together, each containing their own lead-
in, program and lead out.
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Any multisession-supported CD reader can access the data, whether it was
written in the first session or a subsequent session.
Contrast this to the recording structure of a pressed CD-ROM or a CD-R written in
“Disc at Once” mode that contains just one lead-in area and one lead-out area.
What is the Recording Speed of CD-R?
The “speed” rating of a CD-Recordable/Rewritable determines how fast it can record
data to blank CD-R media.
Speed designators, such as “1X”, “2X”, “4X” and “6X” define multiples of the
original playback speed of first generation CD-ROM players:
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For a CD-ROM player or CD-Recordable/Rewritable, a 1X speed trans-
lates to 153,600 Bytes per second. This is usually rounded down to 150 Kb
per second. Therefore, a “1X” recorder writes 150 Kb per second to the
CD-R media.
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Likewise, a “4X” recorder records at 600 Kb per second.
NOTES: 1. There are some variations in measuring speed, because there are recording
modes that provide more than 2,048 data bytes per block (audio is recorded
at 2,352 bytes per block).
2. Some CD-Recordable/Rewritables have a different reading speed than their
rated recording speed. For instance, a “4x4x32” CD-Recordable/Rewritable
can write at 4x speed and read back at 32x speed.