"There are circumstances where an action is required to be executed by a group of people. The idea of secret sharing is to divide a secret into pieces called shares, which are then distributed amongst users by the dealer. The shares provided to the participants are generally forever. But the need of the applications is to periodically renew the shares for the same secret to add more security. Also to add new participants enrolling feature is necessary and sometimes dis-enrollment is required to remove the dishonest participants. For example, to transfer money from a bank a manager and a clerk need to co-operate."