Pre-modded modem on my paid for internet connection

[torro32]

The passphrase is called the shared secret by the ISP's and I don't know of anyway to get it... unless you know the private snmp string, then maybe you could download the config from the CMTS and take a look around and find the shared secret. But that is another thing all together.

you don't have to know the private string to find out the shared secret.