F3726, F3211, F3174, R5135, R3816-HP Firewalls and UTM Devices Access Control Configuration Guide-6PW100

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Before authentication, a user gets a private IP address through DHCP and can access only the
portal server and predefined free websites. After passing authentication, the user is allocated a
public IP address and can access the network resources. No public IP address is allocated to those
who fail authentication. This solves the IP address planning and allocation problem. For example,
a service provider can allocate public IP addresses to broadband users only when they access
networks beyond the residential community network.
• Cross-subnet authentication
Cross-subnet authentication is similar to direct authentication, but it allows Layer 3 forwarding
devices to be present between the authentication client and the access device.
In direct authentication, re-DHCP authentication, and cross-subnet authentication, the client's IP
address is used for client identification. After a client passes authentication, the access device
generates an ACL for the client based on the client's IP address to permit packets from the client to
go through the access port. Because no Layer 3 devices are present between the authentication
clients and the access device in direct authentication and re-DHCP authentication, the access
device can directly learn the clients' MAC addresses, and can enhance the capability of
controlling packet forwarding by also using the learned MAC addresses.
197BPortal support for EAP
Only Layer 3 portal authentication that uses a remote portal server supports EAP authentication.
Authentication by using the username and password is less secure. Digital certificate authentication is
usually used to ensure higher security.
The Extensible Authentication Protocol (EAP) supports several digital certificate-based authentication
methods, for example, EAP-TLS. Working together with EAP, portal authentication can implement digital
certificate-based user authentication.
Figure 124 Portal support for EAP working flow diagram
As shown in 659HFigure 124, the authentication client and the portal server exchange EAP authentication
packets. The portal server and the access device exchange portal authentication packets that carry the
EAP-Message attributes. The access device and the RADIUS server exchange RADIUS packets that carry
the EAP-Message attributes. The RADIUS server that supports the EAP server function processes the EAP
packets encapsulated in the EAP-Message attributes, and provides the EAP authentication result. During
the whole EAP authentication process, the access device does not process the packets that carry the
EAP-Message attributes but only transports them between the portal server and the RADIUS server.
Therefore, no additional configuration is needed on the access device.
NOTE:
• To use portal authentication that supports EAP, the portal server and client must be the HP IMC portal
server and the HP iNode portal client.
• Only Layer 3 portal authentication that uses a remote portal server supports EAP.