Controlling devices using short message service from administrative devices
An administrator charged with responsibility for one or more administered wireless devices can use a wireless device to disable lost or stolen devices using an SMS lost-mode message. The payload of the lost-mode message can be encrypted to prevent malicious attacks. The payload may include a universal device identifier unique to the target device, the phone number of the administrator's device, and a time stamp memorializing command or message creation. Successful decryption authenticates the administrator. Before executing the lost-mode command, however, the target device reviews the unique identifier to verify the target and compares the phone number of the administrator's device with the number identified with the incoming SMS message to authenticate the relaying device. The target device can also consider an embedded time stamp to determine whether the lost-device command has been superseded.
1. A method of controlling a target wireless device designated by a target-wireless-device phone number using an administrative wireless device designated by an administrative-wireless-device phone number, the method comprising:
encrypting a payload that includes the administrative-wireless-device phone number, thereby creating an encrypted payload; and
directing a lost-mode message to the target-wireless-device phone number, the lost-mode message including the encrypted payload.
2. The method of claim 1 , further comprising receiving the encrypted payload at the administrative wireless device.
3. The method of claim 2 , further comprising requesting the encrypted payload responsive to a report identifying the target wireless device.
4. The method of claim 1 , wherein the encrypted payload comprises a lost-mode command.
5. The method of claim 1 , wherein the encrypted payload includes the target-wireless-device phone number.
6. The method of claim 1 , wherein the encrypted payload includes an identifier unique to the target wireless device.
7. The method of claim 1 , wherein the lost-mode message includes a time stamp indicative of a time the lost-mode message was created.
8. The method of claim 7 , further comprising, at the target wireless device:
comparing the time stamp with an earlier-received time stamp associated with another command.
9. The method of claim 1 , further comprising, at the target wireless device:
receiving the lost-mode message accompanied by a sender phone number;
comparing the sender phone number to the administrative-wireless-device phone number; and
executing a lost-mode command responsive to the comparing.
10. A system for controlling a target wireless device designated by a target-wireless-device phone number, the system comprising:
an administrative device designated by an administrative-wireless-device phone number, the administrative device adapted to convey a lost-mode message to the target-wireless-device phone number, the lost-mode message including a payload with a lost-mode command and the administrative-wireless-device phone number, wherein the payload includes the administrative-wireless-device phone number as an encrypted number.
11. The system of claim 10 , wherein the administrative device encrypts the administrative-wireless-device phone number to produce the encrypted number.
12. The system of claim 10 , wherein the lost-mode message specifies the target-wireless-device phone number and a device identifier of the target wireless device.
13. The system of claim 10 , further comprising a server remote from the administrative device, the server to encrypt at least a portion of the payload.
14. The system of claim 10 , further comprising a server to prepare the lost-mode message and convey the lost-mode message to the administrative device.