On the new member＇s subsecret distribution protocol in dynamic group secret-sharing

Secret-sharing is a common method to protect important data, such as the private key of a public-key system. Dynamic Group Secret-sharing (DGS) is a system where all of the members in a group hold a subsecret of the key information and where the number of members in the group is variable. This kind of secret-sharing is broadly used in many special distribution systems, such as Self-secure Ad-hoc Network. Distributing this subsecret to a new member when he enters the group is the common method that ensures all the members participate in the same secret-sharing. However, no' atisfactory subsecret distribution scheme exists at present. This paper proposes a new protocol that tries to satisfy both security and efficiency.