Well, there is a lot of articles about that out there. If any admin could post a link to that, i think Hirakawa will be happier.
ATIP: Absolute Time In Pregroove, and it is the required info that a recorder needs to write a disc.
There is also a lot of tools to read that, and haven't any name yet, but i guess a lot of people here could help u this way.
So now, u can think yourself what media has ATIP, and what hasn't.
Every silver disc ( original one) hasn't it, so CD-ROM and DVD-ROM haven't got, when CD-R(W) and DVD-R(W) have it.
DVD+R(W) uses another technics (ADIP) so this case is not applicable.
I do not know DVD-RAM specs, so can't give u accurate info about.
And finally, ATIP is not a sector nor a zone. ATIP is present in the whole CD/DVD cause a recorder laser beam must know where it is burning everytime. ATIP can be recognized at the Pre-GAP and in the TOC, but obviously is present wherever u see.
And i think i cannot say more a bout. Spath is the expert on that, so he can give u more links if needed.