This read-write setting selects whether 802.1x credentials are validated against a small locally stored user table on the switch itself or against an external RADIUS server. An admin chooses radius for centralized credential management across many switches rather than maintaining separate local user lists on each device. For example, selecting the RADIUS option lets the switch defer every 802.1x authentication decision to the corporate RADIUS server instead of relying on a handful of accounts stored locally on the ES8510 itself.