Configuring & Using IPSec VPNs Cont.
Kyle Amon,  Page 27
/etc/isakmpd/isakmpd.policy

keynote-version: 2
authorizer: "POLICY"
licensees:  "subshared"
conditions: app_domain == "IPsec policy" &&
            esp_present == "yes" &&
            esp_enc_alg != "null" -> "true";

authorizer: "subshared" 
comment: policy delegating to a passphrase
licensees: "passphrase:non-trivial-secret"