Patent ID: 8464067

Claim:
A method for enabling limitation of service access, wherein a service provider (SP) offers at least one service (SR) and wherein a user (U) possesses multiple different digital identities I i that can be used to invoke or register with said service (SR), access to said service (SR) requiring an account at a third party entity, wherein the user (U) registers his digital identities I i with said account and wherein the user (U) agrees on a secret S with said third party entity, the method comprising the steps of: assigning to the user's (U) different digital identities I i counter values k i,SR ; the user (U) requesting said service (SR) employing a specific digital identity I i and calculating a verification value—first verification value v 1 —by applying an encryption algorithm H on said secret S and said counter value k i,SR assigned to the digital identity I i employed for said service request; and said third party entity receiving said first verification value v 1 , applying said encryption algorithm H to reconstruct said employed counter value k i,SR and providing information of whether the reconstructed counter value k i,SR exceeds a limit lim SR , wherein said user (U), in the context of accessing said service (SR), calculates a value p by applying encryption algorithm H on said secret S and said service identifier I SR , and wherein said user (U) calculates said first verification value v 1 by applying encryption algorithm H on said value p and said counter value k i,SR .