<Global Settings>
Http Configuration → Change Password (available from firmware V650Bxx, a change requires the http_user and http_pass credentials)
<http_basic_pass>VALIDVALUE</http_basic_pass>
It defines the HTTP password for the lower-level user (starting from firmware V610Bxx), together with http_basic_user it can be configured to grant access to some of the pages on the web interface (NOTICE: the higher level access will continue to be granted by http_user and http_pass).
e.g. admin
N/A: starting from firmware V530B2 the base station will prompt to change the default credentials on the first login