Knowledge check

Key ceremonies and the HSM key hierarchy: where every payment key comes from

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Question 1 of 10

What is the difference between dual control and split knowledge?

Question 2 of 10

Why is a double-length TDES key split into full-length XOR components rather than into its left and right halves?

Question 3 of 10

Three custodians hold XOR components of a key. Two of them collude. What do they learn about the key?

Question 4 of 10

How is the key check value of a TDES key computed?

Question 5 of 10

Why is a KCV truncated to a few bytes instead of showing the whole encrypted zero block?

Question 6 of 10

Two odd-parity TDES components are XORed together. What happens to parity, and does it matter for the KCV?

Question 7 of 10

In a payment HSM key hierarchy, where are ZMKs, ZPKs, PVKs and CVKs normally stored?

Question 8 of 10

An HSM's LMK is rotated: every stored key is translated from the old LMK to the new one. What happens to the keys' cryptograms and KCVs?

Question 9 of 10

What problem do LMK variants and TR-31 key blocks both solve?

Question 10 of 10

Why have payment organizations moved toward TR-34 and ECDH-based key exchange?

0 / 10 answered