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When WEP was the only standards-based encrpytion method, EAP authentication produced Session Keys (WEP keys used for encrypting unicast data) at the supplicant (station) and authentication server. The AP would produce a Broadcast/Multicast WEP Key.

When WPA (TKIP) or WPA2 (CCMP) encryption are used, EAP authentication produces a PMK (key material used for unicast data) at the supplicant and authentication server. The AP produces a GMK, which is key material for broadcast and multicast data.

The bottom line is that the EAP process stays the same. Supplicant and authentication server negotiate encryption information for unicast data while the AP creates encryption information for broadcast/multicast data.

The real difference is what happens after authentication. When WPA or WPA2 encryption are used, the PMK and GMK (key material) are used during the 4-Way Handshake to create the PTK (unicast) and GTK (broadcast/multicast), which are encryption keys. The PTK and GTK are actually *the same* for both WPA and WPA2 encryption.