Systems, methods, and apparatus are provided for generating verification data that may be used for validation of a wireless transmit-receive unit (WTRU). The verification data may be generated using a tree structure having protected registers, represented as root nodes, and component measurements, represented as leaf nodes. The verification data may be used to validate the WTRU. The validation may be performed using split-validation, which is a form of validation described that distributes validation tasks between two or more network entities. Subtree certification is also described, wherein a subtree of the tree structure may be certified by a third party.