Differences between incremental and differential

As far as I understand TI 9: Incremental backups do not refer to the base (the first full) backup but to the last incremental file. For restoring I need an incremental file, the first full backup and all the files in between.

Differential backups refer always to the first full backup. I should have one full backup and one differential and can use the one or the other (logically one, due to file size limitations there may be multiple physical files).

Questions:
1) Why do I have multiple differential backup files (that means images with different time stamps)? Differential seems to have the same behavior like incremental?

2) What is the real benefit of differential backup if it doesn't safe diskspace? My impression at announcement was that the current differential file will be deleted by the new one. This seems not to be the case.

Thanks for clarification - Hemputi

 

I don't use either incremental or differential TI backups but they way I see it is that if you have all the "versions" you can restore to any given point in time.

The advantage of the differential is that it should be quicker to restore to the final version. Another program's documentation expresses it like this:
Incremental: fast to create, slower to restore.
Differential: fast to restore, slower to create

 

Previous differentials are not automatically deleted by a new differential and I can't recall having seen any Acronis material that suggested that they would be.

If you were to compare, say, a week of differentials every day to a week of incrementals every day, then the differentials would actually take up quite a bit more space than the incrementals. The point is that the old differentials can be deleted if you wish to do so. As you have stated, you need the original and ALL incrementals backwards from your restore point to be able to do a restore and so none can be deleted.

See above.

 

Thank you for your help. I've also found a FAQ article at an Acronis site wich clarifies a lot on TI 9.
http://www.acronis.com/homecomputing/products/trueimage/faq.html#7