Methods and apparatus for locking communications devices
First Claim
1. A method of unlocking a pre-locked device, the device adapted to receive signals from a remotely located facility, and further adapted to receive, and having received, an identification module containing a first value and a second value, the method comprising the steps of:
- computing a key as a function of a signal received from the remotely located facility;
computing a checkword as a function of the key and the first identification module value;
comparing the checkword with the second identification module value; and
if the checkword matches the second identification module value, unlocking the device for operation.
3 Assignments
0 Petitions
Accused Products
Abstract
An apparatus and method for locking and unlocking mobile telecommunications handsets or other devices is disclosed. Each handset is unactivated at the time of purchase. Other than emergency calls, or account activation, no calls can be made using the handset unless it has been unlocked. The handset is capable of receiving a readable subscriber identity module (SIM) having a network (or other) ID and a codeword, and its operation is to be locked and unlocked with respect to the entity corresponding to the ID on the SIM. Furthermore, the handset includes a processor programmed with a unique equipment identification number and a key. All handsets manufactured as part of a particular batch may include the key, which is burned or otherwise written into a memory area of the handset so that it may not be read without its being destroyed. The handset processor is also programmed to produce a handset-specific key as a function of the equipment identification number and the batch-specific key. Upon activation of the handset, the customer service center associated with the network operator transmits a modifier to the handset. The handset changes its handset-specific key according to the modifier to yield an operator-specific key. The resulting operator-specific key is used in conjunction with the network (or other) ID (from the SIM) to produce a checkword. If the checkword matches the codeword, which is read off the SIM, the handset is unlocked (i.e., enabled) for normal use. Other features of the invention include re-locking the handset according to similar principles, and providing a personal identification number for permanently unlocking the device, so that it can be used with any compatible SIM.
250 Citations
29 Claims
-
1. A method of unlocking a pre-locked device, the device adapted to receive signals from a remotely located facility, and further adapted to receive, and having received, an identification module containing a first value and a second value, the method comprising the steps of:
-
computing a key as a function of a signal received from the remotely located facility; computing a checkword as a function of the key and the first identification module value; comparing the checkword with the second identification module value; and if the checkword matches the second identification module value, unlocking the device for operation. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25)
-
-
26. A method of locking a wireless telecommunications terminal such that it can be unlocked for use only with proper authorization by a controlling wireless telecommunications system operator, the telecommunications terminal being one of a batch of such terminals and being uniquely identified by an equipment identification number, proper authorization being provided in the form of a subscriber identification module (SIM) containing information readable by the telecommunications terminal, the readable SIM information including an identification code and a codeword, the method comprising the steps of:
a. providing the telecommunications terminal with an operator-specific key, comprising the following steps; - View Dependent Claims (28)
-
27. providing the telecommunications terminal with a first key unique to the batch from which the terminal derived, the key being known to the controlling operator;
-
2. computing a second key unique to the terminal, the second key being a function of the equipment identification number and the first key, the computation being performed by the telecommunications terminal; 3. transmitting a modifier to the terminal at time of activation, the modifier being used by the terminal; and 4. computing a third, operator-specific key as a function of the second key and the modifier, the operator-specific key being common to all activated terminals under the control of the controlling operator; b. computing a checkword, comprising the following steps; 1. reading the identification code from the SIM; 2. transforming at least a subset of the identification code as a function of the operator-specific key to yield a checkword; c. reading the codeword from the SIM; d. comparing the checkword with the codeword; and e. if the checkword and the codeword match, unlocking the terminal.
-
-
29. A subscriber identification module for unlocking a telecommunications terminal for communicating over a network administrated by a network operator, the subscriber identification module comprising memory means readable by the telecommunications terminal, the memory means containing, alternatively instructions, instructions and data and data comprising a subscriber identification code and a codeword, the codeword being derivable by transforming the subscriber identification number according to a key that is a function of a key particular to the terminal and a modifier transmitted to the terminal by the network operator.
Specification