Patent ID: 8719920

Claim:
A system comprising: a multi-touch interactive surface; an identifier module coupled to the multi-touch interactive surface to identify an attribute of an entity that is proximate to the interactive surface via an electromagnetic signal from the entity, wherein the entity is a participant in a multi-participant activity supported by the multi-touch interactive surface; memory coupled to the multi-touch interactive surface to store data on attributes of entities; a compare module coupled to the identifier module to compare the identified attribute to the stored data on attributes and to determine a presence of the identified attribute in the memory; and an assignment module to assign an identifier to the identified attribute when the identifier is absent from the memory, wherein the identifier is based on the identified attribute and a location of the entity relative to the multi-touch interactive surface, and the identifier is for authenticating the entity, and wherein the identifier module bases its action on a predetermined attribute hierarchy, and wherein the identified attribute identified by the identifier module is a cell phone desktop background of the participant, and wherein the assignment module performs the assignment based on the identified cell phone desktop background of the participant.