Section: 4.7.1.3 P-TMSI signature
Content: The network may assign a P-TMSI signature to an MS in an attach, routing area update, or P-TMSI reallocation procedure. Only in combination with a valid P-TMSI, this P-TMSI signature is used by the MS for authentication and identification purposes in the subsequent attach, routing area update or detach procedure. If the MS has no valid P-TMSI it shall not use the P-TMSI signature in the subsequent attach, routing area update or detach procedure. Upon successful completion of the subsequent attach or routing area update procedure, the used P-TMSI signature shall be deleted. Upon completion of an MS initiated detach procedure, the used P-TMSI signature shall be deleted. Upon completion of a network initiated detach procedure the P-TMSI signature shall be kept, unless explicitly specified otherwise in subclause 4.7.4.2.2.