Migration from different backup tool to Netback

Hi All,

I was confused about how to mange old backup tape?

We consolidated our 10 small dc to one dc.

Old DC Backup tool - backup exec, netbackup, arch serv.
NewDC backup tool - Netbackup 7.5

So my concern - as old DC will be decommission soon, after that how i can restore backup from old tapes which was backed up by existing tool.

Please suggest me some... Ways....to that...

Thanks
Pradeep Jadli