The freenode IRC network has for a long time supported connecting and automatic identification using SASL.

Recently, the freenode network deprecated the commonly used SASL mechanism DH-BLOWFISH due to security concerns, causing my IRC client (irssi) to no longer be able to authenticate.

Unfortunately, while scripts and guides describing using irssi with DH-BLOWFISH are plentiful, it seems the steps required to use the new preferred ECDSA-NIST256P-CHALLENGE method are not yet documented.

Read on for a step-by-step walk-through of configuring irssi to use SASL with freenode in 2015.