What is the different between following Symantec backup license

SYMC BACKUP EXEC 2010 SERVER WIN PER SERVER RENEWAL ESSENTIAL 12 MONTHS ACAD BAND S

--this is specifiaclly for Backup Exec 2010 Server renewal, this is for the base license

SYMC SYSTEM RECOVERY SERVER 2011 WIN PER SERVER RENEWAL ESSENTIAL 12 MONTHS ACAD BAND S

--this is for Backup Exec System Recovery Server, the imaging software to be used for imaging to be used for fast restores and dissimilar hardware resotres



SYMC BACKUP EXEC 2010 AGENT FOR WINDOWS SYSTEMS WIN PER SERVER RENEWAL ESSENTIAL 12 MONTHS ACAD BAND S

Thsi is for Backup Exec (reference base) Exchange agent to allow you backup Exchange information store and granular backups/restores of mailboxes

I do have another one which is used for Exchange:

SYMC BACKUP EXEC 2010 AGENT FOR MSFT EXCHANGE WIN PER SERVER RENEWAL ESSENTIAL 12 MONTHS ACAD BAND S

are you sure (SYMC BACKUP EXEC 2010 AGENT FOR WINDOWS SYSTEMS) is for agent. because we removed our exchange server, i will not be needing it to reinstall it.



at the same time:
SYMC BACKUP EXEC 2010 OPTION LIBRARY EXPANSION WIN PER DEVICE RENEWAL ESSENTIAL 12 MONTHS ACAD BAND S

is this for Library Tape?

I think below backup is for normal file backup located under server?

SYMC BACKUP EXEC 2010 AGENT FOR WINDOWS SYSTEMS WIN PER SERVER RENEWAL ESSENTIAL 12 MONTHS ACAD BAND S

thanks