Dell C9000 Series Networking Configuration Manual page 119

When multiple end users are connected to a single authenticator port, single-host mode authentication does
not authenticate all end users, and all but one are denied access to the network. For these cases, the Dell
Networking OS supports multi-host mode authentication.
Figure 9. Multi-Host Authentication Mode
When you configure multi-host mode authentication, the first client to respond to an identity request is
authenticated and subsequent responses are still ignored. However, because the authenticator expects the
possibility of multiple responses, no system log is generated. After the first supplicant is authenticated, all end
users connected to the authorized port are allowed to access the network.
If the authorized port becomes unauthorized due to re-authentication failure or the supplicant sends an
EAPOL logoff frame, all connected end users are denied access to the network.
If you change the host mode on a port that is already authenticated:
• From single-host to multi-host — All devices connected to the port that were previously blocked may
access the network; the supplicant does not re-authenticate.
• From multi-host to single-host — The port restarts the authentication process. The first end user to
respond is authenticated and allowed access.
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