R2511-HP MSR Router Series Security Configuration Guide(V5)

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Configuring HABP
The HW Authentication Bypass Protocol (HABP) is intended to enable the downstream network devices
of an access device to bypass 802.1X authentication and MAC authentication configured on the access
device.
As shown in Figure 142, 8
02.1X authenticator Switch A has two switches attached to it: Switch B and
Switch C. On Switch A, 802.1X authentication is enabled globally and on the ports connecting the
downstream network devices. The end-user devices (the supplicants) run the 802.1X client software for
802.1X authentication.
The communication between Switch B and Switch D, where the 802.1X client is not supported (which is
typical of network devices), will fail because they cannot pass 802.1X authentication and their packets
will be blocked on Switch A. To allow the two switches to communicate, you can use HABP.
Figure 142 Network diagram for HABP application
HABP is a link layer protocol that works above the MAC layer. HABP is built on the client-server model.
Generally, the HABP server is enabled on the authentication device that is configured with 802.1X or
MAC authentication (such as Switch A in Figure 142)
, and the attached switches function as the HABP
clients (such as Switch B through Switch E in Figure 142)
. No device can function as both an HABP server
and a client at the same time.
Typically, the HABP server sends HABP requests to all its clients periodically to collect their MAC
addresses, and the clients respond to the requests. After the server learns the MAC addresses of all the
clients, it registers the MAC addresses as HABP entries. Then, link layer frames exchanged between the
clients can bypass the 802.1X authentication on ports of the server without affecting the normal operation
of the whole network.
All HABP packets must travel in a specific VLAN. Communication between the HABP server and HABP
clients is implemented through this specific VLAN.