System and method for compressing secure e-mail for exchange with a mobile data communication device

• US 7,657,736 B2
• Filed: 07/11/2007
• Issued: 02/02/2010
• Est. Priority Date: 06/12/2001
• Status: Expired due to Term

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Cherry, Carl L., Adams, Neil P., Brown, Michael S., Brown, Michael K., Godfrey, James A., Little, Herbert A., Tyhurst, Timothy R.
• Primary Examiner(s): Revak; Christopher A
• Application Number:
  US11/776,099
• Publication Number:
  US 20080016359A1
• Time in Patent Office: 937 Days
• Field of Search: None
• US Class Current: 713/150
• CPC Class Codes: G06Q 10/107 Computer-aided management of electronic mailing [e-mailing]
• CPC Class Codes: H04L 2463/062 applying encryption of the keys cryptographic mechanisms or cryptographic arrangements for key distribution using key encryption key H04L9/0822
• CPC Class Codes: H04L 51/066 Format adaptation, e.g. format conversion or compression
• CPC Class Codes: H04L 51/58 Message adaptation for wireless communication
• CPC Class Codes: H04L 63/0442 wherein the sending and receiving network entities apply asymmetric encryption, i.e. different keys for encryption and decryption cryptographic mechanisms or cryptographic arrangements for public-key encryption H04L9/30
• CPC Class Codes: H04L 63/045 wherein the sending and receiving network entities apply hybrid encryption, i.e. combination of symmetric and asymmetric encryption cryptographic mechanisms or cryptographic arrangements using a plurality of keys or algorithms H04L9/14
• CPC Class Codes: H04L 63/062 for key distribution, e.g. centrally by trusted party cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819
• CPC Class Codes: H04L 63/101 Access control lists [ACL]
• CPC Class Codes: H04L 63/126 the source of the received data
• CPC Class Codes: H04L 67/04 specially adapted for terminals or networks with limited capabilities; specially adapted for terminal portability
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 67/5651 Reducing the amount or size of exchanged application data
• CPC Class Codes: H04L 69/04 Protocols for data compression, e.g. ROHC
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04W 12/02 Protecting privacy or anonymity, e.g. protecting personally identifiable information [PII]
• CPC Class Codes: H04W 12/033 of the user plane, e.g. user's traffic
• CPC Class Codes: H04W 12/10 Integrity
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 4/12 Messaging; Mailboxes; Announcements
• CPC Class Codes: H04W 4/16 : Communication-related supplementary services, e.g. call-transfer or call-hold

Abstract

A system and method are provided for pre-processing encrypted and/or signed messages at a host system before the message is transmitted to a wireless mobile communication device. The message is received at the host system from a message sender. There is a determination as to whether any of the message receivers has a corresponding wireless mobile communication device. For each message receiver that has a corresponding wireless mobile communication device: the message is processed so as to modify the message with respect to encryption and/or authentication aspect. The processed message is transmitted to a wireless mobile communication device that corresponds to the first message receiver. The system and method may include post-processing messages sent from a wireless mobile communications device to a remote system. Authentication and/or encryption message processing is performed upon the message. The processed message may then be sent through the remote system to one or more receivers.

Claims

1. A method of reducing size of an encrypted message at a host system before the encrypted message is transmitted to a wireless mobile communication device, the method comprising the steps of:

(a) receiving at the host system the encrypted message from a message sender addressed to first and second message receivers, the encrypted message including an encrypted message body and an encrypted session key for each of the message receivers, wherein the encrypted message received at the host system comprises an e-mail message;

(b) generating at the host system a first reduced size encrypted message that contains the encrypted message body and the encrypted session key for the first message receiver, the first reduced size encrypted message not including the encrypted session key for the second message receiver; and

(c) transmitting the first reduced size encrypted message to the wireless mobile communication device that corresponds to the first message receiver;

wherein the encrypted session keys were encrypted via public keys that are electronically available from different companies over a network to which the host system is connected.

2. The method of claim 1, wherein the step of generating the first reduced size encrypted message comprises the step of removing the encrypted session key other than the encrypted session key for the first message receiver in order to form the first reduced size encrypted message.

3. The method of claim 1, wherein the step of generating the first reduced size encrypted message comprises the step of removing all encrypted session keys other than the encrypted session key for the first message receiver in order to form the first reduced size encrypted message.

4. The method of claim 3, wherein the step of generating the first reduced size encrypted message comprises the step of removing a message receiver information field of the message which maps each encrypted session key to a message recipient.

5. The method of claim 1, wherein the message receivers to which the encrypted message is addressed were specifically chosen by the message sender.

6. The method of claim 1 wherein:

the receiving step (a) comprises the step of receiving at the host system the encrypted message from the message sender addressed to a plurality of message receivers, the encrypted message including the encrypted message body and the encrypted session key for each message receiver;

the method further comprises the step of determining whether any of the message receivers has a corresponding wireless mobile communication device;

the generating step (b) comprises the step of, for each message receiver that is determined to have a corresponding wireless mobile communication device, generating a respective reduced size encrypted message containing the encrypted message body and the encrypted session key only for the message receiver; and

the transmitting step (c) comprises the step of transmitting the reduced size encrypted message to the corresponding wireless mobile communication device.

7. The method of claim 6, wherein a single address is shared by the respective message receiver and the corresponding wireless mobile communication device.

8. The method of claim 6, wherein each encrypted session key is encrypted using a public key of the message receiver;

wherein the message receiver and the corresponding wireless mobile communication device share the public key and an associated private key.

9. The method of claim 1, wherein the encrypted message comprises a message that had been signed and then encrypted, and further includes an encrypted digital signature;

and

the step of generating the first reduced size encrypted message comprises the step of generating a reduced size encrypted message containing the encrypted message body, the encrypted digital signature and the encrypted session key for the first message receiver.

10. The method of claim 9, wherein:

the encrypted message further comprises encrypted signature-related information; and

the step of generating the first reduced size encrypted message comprises the step of generating the reduced size encrypted message containing the encrypted message body, the encrypted digital signature, the encrypted signature-related information and the encrypted session key for the first message receiver.

11. The method of claim 1, wherein the encrypted message comprises a Secure Multipurpose Internet Mail Extensions (S/MIME) e-mail message.

12. The method of claim 1, wherein the encrypted message is encrypted according to Pretty Good Privacy.

13. A system for reducing the size of an encrypted message for transmission to a wireless mobile communication device, the system comprising:

a host system configured to receive an encrypted message from a message sender and addressed to message receivers, the encrypted message including an encrypted message body and an encrypted session key for each message receiver, wherein the received encrypted message is an e-mail message; and

a wireless connector system associated with the host system and configured to determine whether any of the message receivers has a corresponding wireless mobile connection device and if so, for each message receiver that has a corresponding wireless mobile communication device, to generate a reduced size encrypted message containing the message body and the encrypted session key only for the message receiver and to transmit the reduced size encrypted message to the wireless mobile communication device, wherein at least two of the encrypted session keys for the message receivers were encrypted via public keys that are electronically available from different companies over a network to which the host system is connected.

14. The system of claim 13, wherein the host system comprises a message server system.

15. The system of claim 14, wherein the message server system is implemented in a secure network behind a network security firewall.

16. The system of claim 13, wherein the host system comprises a desktop computer system or a laptop computer system.

17. The system of claim 13, wherein a network operator infrastructure enables wireless information exchange between the host system and wireless mobile communication devices.

18. A system for reducing size of an encrypted message at a host system before the encrypted message is transmitted to a wireless mobile communication device, said system comprising:

means for receiving at the host system the encrypted message from a message sender addressed to first and second message receivers, the encrypted message including an encrypted message body and an encrypted session key for each of the message receivers, wherein the encrypted message received at the host system comprises an e-mail message;

means for generating at the host system a first reduced size encrypted message that contains the encrypted message body and the encrypted session key for the first message receiver, the first reduced size encrypted message not including the encrypted session key for the second message receiver; and

means for transmitting the first reduced size encrypted message to the wireless mobile communication device that corresponds to the first message receiver,

wherein the encrypted session keys were encrypted via public keys that are electronically available from different companies over a network to which the host system is connected, and

wherein different electronic security messaging approaches are used to encrypt messages sent to the host system.

19. A wireless device comprising memory for storing a first reduced size encrypted message, wherein the first reduced size encrypted message was generated by a remote system based upon an encrypted message provided to the remote system from a message sender, said encrypted message from the message sender comprising an e-mail message and having contained addresses to first and second message receivers, the sender'"'"'s encrypted message including an encrypted message body and an encrypted session key for each of the message receivers,

wherein the first reduced size encrypted message contains the encrypted message body and the encrypted session key for the first message receiver, the first reduced size encrypted message sent by the remote system to the wireless device not including the encrypted session key for the second message receiver, wherein the encrypted session keys were encrypted via public keys that are electronically available from different companies over a network to which the host system is connected.

20. The wireless device of claim 19 wherein the wireless device has an association with the first message receiver, said association indicating that the wireless device is to receive messages sent to the first message receiver.

21. The wireless device of claim 19 wherein the remote system comprises host system means.

22. The wireless device of claim 19 wherein the host system means comprises wireless connection system means.

23. A method of processing an encoded message at a host system before the encoded message is transmitted to a wireless mobile communication device, the method comprising the steps of:

receiving at the host system the encoded message from a message sender addressed to a plurality of message receivers;

wherein the received encoded message comprises an e-mail message;

wherein at least portions of the encoded message were encoded via electronic asymmetric security keys that are electronically available from different companies over a network to which the host system is connected;

determining whether any of the message receivers has a corresponding wireless mobile communication device; and

for each message receiver that has a corresponding wireless mobile communication device;

processing the message so as to modify the message with respect to an encoding aspect, said encoding aspect being, selected from the group consisting of an encryption aspect, an authentication aspect, and combinations thereof; and

transmitting the processed message to the connecting wireless mobile communication device.