There is no need.
You might use CTxxxxL4 barcode for example to show it is a catalog tape (xxxx is a number) if you really want to but I wouldn't receoomend anythig further than that.
You cannot control what tapes are used down to a paricular date (well, you can but it's not 'easy' as NBU is not designed to do this).
The answer as to why you don't need to do this is simply the DR file - this tells you (and NBU during a catalog recovery ) which tapes are required. Simply make sure the DR file is emailed out so that a copy is off the server.
Not sure why you have so many catalog tapes (unless you have a very big catalog) - as soon as a new catalog is taken, the old ones are redundant (well, anything older than the last full, if you use incrementals) - but I would always recommend keeping catalog backups for at least a month, 2 months would be even better. You would never recover from these as they are so out of date, but sometimes we (support) would look back at what was happening in a catalog some days/ weeks ago to help investigate an issue.
Being able to identify the catalog tapes would be neat (eg the CTxxxx barcode) as if the DR files were lost you could identify the tapes, they could simply be scanned in then (phase 1 only) to find the most recent, running phase 2 on the most recent would rebuild the catalog and thus the DR file.
However that said, there is no excuse for losing the DR files. Persoanlly I would email them out and save a copy to a network share, thus having two copies sent off the master server.
