Remote Synthetic Backups

Hi,

 

I have a client who is currently doing a full backup daily of around 50Gb to a NAS service at the end of a 10mbit Lan Extension.  The backup used to run in the required time window but its grown and now I need to look at another solution.

 

I would like to use Synthetic backups but i'm worried about two aspects:

 

1). To generate a synthetic backup will the Backup Server need to read data from the baseline and the incrementals in order to create the new synthetic backup, if so then surely this will take longer as it'll have to read a load of data from the remote NAS and then once its made the backup, copy it all down the line again in full

 

2). Can I incrementally backup Exchange or is it a full backup every time?  currently the exchange server is worth about 20Gb of the total backup so this would limit any savings I make?

 

Could I possibly solve this issue by having a 2nd nas local to the data being backed up and then simply performs my synthetics on this and then duplicate them down to the offsite nas?

 

From what I can see I can only benefit from Synthetics if the disk backup is local to the backup exec server itself.

 

Thankyou

 

Dave