What makes using an Oracle Wallet to connect to a data source more secure than using a username and password to do the same?
Wallets can be configured to only be valid from a specific client, so
access to the specific host is also required, whereas
username/password text can be easily ported elsewhere with
copy/paste.
Using wallets also allows most applications to be redeployed between
environments (like dev and prod) without requiring reconfiguration or
changes to credentials.
Placing the credentials in an external store allows password
management policies to be more easily enforced without changing
application code whenever user names or passwords change.