Which of the following CHAP Authentication mechanisms is available when using
Software iSCSI, but not Hardware iSCSI? Select all that apply.

A.
Per-Target CHAP

B.
Per-Subnet CHAP

C.
Mutual CHAP

D.
One-way CHAP

Explanation:

Software iSCSI support BOTH Per-Target and Mutual CHAP.
For Softare iSCSI only, you can set one-way CHAP and mutual CHAP for each initiator
or at the target level.
Hardware iSCSI support CHAP only at the initiator level.
iSCSI SAN Configuration Guide ESX 4.0 ESXi 4.0 vCenter Server 4.0, page 37.
ESX/ESXi supports CHAP authentication at the adapter level. In this case, all targets
receive the same CHAP name and secret from the iSCSI initiator. For software iSCSI,
ESX/ESXi also supports per-target CHAP authentication, which allows you to configure
different credentials for each target to achieve greater level of security.