Authenticated Blind Issuing of Symmetric Keys for Mobile Access Control System without Trusted Parties

Table 3

Possible storage of a key owner 𝒰_𝑖.

Status	Guard system	Key	Valid time	Issuer	Key status
⟨𝒜⟩	ID𝒢1	𝒦𝒰1	VT𝒰1	N/A	ok
⟨𝒮⟩	ID𝒢2	𝒦𝒰2	VT𝒰2	ID𝒰1	ok
⟨𝒰⟩	ID𝒢3	𝒦𝒰3	VT𝒰3	ID𝒰1	EMK𝒰3
⟨𝒰⟩	ID𝒢4	𝒦𝒰4	VT𝒰4	ID𝒰2	ok