Getting Started: SASL
Freenode IRC Network supports Simple Authentication and Security Layer (SASL). This feature is open for users to utilize, specifically on Freenode.
Essentially, it is a secure method / mechanism to authenticate to the nickname service robot called NickServ that resides on the network — automatically upon connecting to the network.
First and foremost, load the SASL module on your ZNC account. You can do so by executing:
/msg *status loadmodule sasl
Next, set the mechanism. In this case, "Plain", a cleartext password mechanism. Note that 'DH-BLOWFISH' & 'DH-AES' mechanism have been depreciated. You should be good with 'Plain'.
/msg *sasl Mechanism PLAIN
Now insert your Account Username and Password:
/msg *sasl Set _Account_Username_ _Password_
Done. You should be automatically authenticated to services as soon as you connect to the network.
Strict-and-Grumpy Security Guard
You have the option to use Force. Lucky you. — If the SASL authentication process is successful, it will give your IRC Bouncer (ZNC) the green light to connect to the given IRC Network, in this case Freenode. — You also have the option to have your IRC Bouncer (ZNC) not connect when SASL fails to authenticate you to the services (NickServ) for some oddball reason. You can set the 'RequireAuth' option as so:
/msg *sasl RequireAuth yes
And to disable this feature, simply execute:
/msg *sasl RequireAuth no