本文对应《A Practical Guide to TPM 2.0 — Using the Trusted Platform Module in the New Age of Security》的第8章第1节第2部分。
Ephemeral Hierarchy —— 临时性层级
TPM 2.0 has an ephemeral hierarchy called the NULL hierarchy, which is also referenced
by a permanent handle: TPM_RH_NULL (0x40000007). This hierarchy is utilized when
the TPM is being used as a cryptographic coprocessor, as described in Chapter 9. Its
authorization value and policy are both always NULL.
TPM 2.0有一个叫作空层级的临时性层级,它也被一个永久性句柄引用:TPM_RH_NULL(0x40000007)。此层级当TPM被作为密码协处理器使用时会被使用到,如第9章中所描述。它的授权值和策略两者俱总为空。
Similar to the persistent hierarchies, the ephemeral hierarchy is permanent.