I am unable to find any literature to evaluate which solution to use when backing up my Oracle 11g DB. The attempt is to perform online backups by enabling ARCHIVELOG mode.
Edit: I have gone through individual documentation for RMAN and VSS Writer. I am looking for comparative analysis.
Oracle has some documentation on the topic: Performing Database Backup and Recovery with VSS.
Both VSS and RMAN looks good to me, the main difference is how you can use it:
The main advantage of RMAN is the use of the catalog. It stores informations of the latest backups and allow to easily restore data.
VSS will work at a lower level, without your database being aware that it is backed-up. But VSS will allow you to backup your database using the same way (and tools) that you can use to backup a file server or an SQL-Server database.
I think the documentation you are looking for is this, which documents how to backup Oracle 11g databases using the Recovery Manager (RMAN) tool. The documentation can also be found in HTML format here