Privacy and security mechanism for presence systems with tuple spaces

• US 7,472,268 B2
• Filed: 08/12/2003
• Issued: 12/30/2008
• Est. Priority Date: 08/12/2002
• Status: Active Grant

• Current Assignee: RingCentral Incorporated
• Original Assignee: Mitel Networks Corporation
• Inventors: Gray, Thomas A.
• Primary Examiner(s): Vu; KimYen
• Assistant Examiner(s): Shan; April Y
• Application Number:
  US10/638,416
• Publication Number:
  US 20040032940A1
• Time in Patent Office: 1,967 Days
• Field of Search: 726/2, 726/4, 726/14, 379/188, 713/150, 713/171, 380/259, 380/277, 380/278, 705/71
• US Class Current: 713/150
• CPC Class Codes: G06Q 20/3829 involving key management
• CPC Class Codes: H04L 61/45 Network directories; Name-to-address mapping
• CPC Class Codes: H04L 63/0464 using hop-by-hop encryption, i.e. wherein an intermediate entity decrypts the information and re-encrypts it before forwarding it
• 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 63/068 using time-dependent keys, e.g. periodically changing keys cryptographic mechanisms or cryptographic arrangements for controlling usage of secret information H04L9/088
• CPC Class Codes: H04L 67/54 Presence management, e.g. monitoring or registration for receipt of user log-on information, or the connection status of the users
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04M 3/42 Systems providing special services or facilities to subscribers specially adapted for wireless communication networks H04W4/00
• CPC Class Codes: H04M 3/42093 Notifying the calling party of information on the called or connected party
• CPC Class Codes: H04M 3/42365 Presence services providing information on the willingness to communicate or the ability to communicate in terms of media capability or network connectivity

Abstract

A system is provided for cycling encryption keys to prevent the guessing of encrypted presence information in a shared information space. The system of the invention prevents malicious publication of presence information and ensures that only valid presence information is published to the shared information space. A malicious subscriber is prevented from knowing that he/she has been detected while a search is underway to determine his/her identity. During such a search, authorized subscribers are shifted to a new source of presence information while the malicious subscriber remains at the previous source.

Claims

1. A communication system for privately and securely exchanging information about a first entity with at least one further entity, comprising:

a presence memory to store tuples that contain said information;

a presentity to publish encrypted information about said first entity to said presence memory, wherein said information comprises a unique identifier of said presentity, said unique identifier comprising a random string concatenated to an identifier key, and wherein said presentity is enabled to;

encrypt said information with a unique key provided by said presentity to create said encrypted information;

post said encrypted information to said presence memory;

change said unique key to a new unique key at random intervals;

re-encrypt said encrypted information with said new unique key to create re-encrypted information; and

re-post said re-encrypted information to said presence memory at said random intervals, and wherein said re-encrypt and said re-post are repeated when presence information changes in presence information comprising changes in location of a user;

sensors for detecting presence of the first entity, said presentity connected to said sensors;

a watcher agent associated with said at least one further entity to post a subscribe tuple to said presence memory to initiate a subscription to said information published by said presentity via said post and said re-post;

a presentity agent associated with said first entity to return subscribe-reply messages, a first subscribe-reply message containing said unique key to subscribe said further entity to said encrypted information published by said presentity, and a second subscribe-reply message containing said new unique key to subscribe said further entity to said re-encrypted information published by said presentity; and

a watcher associated with said further entity to monitor said presence memory and decrypt said encrypted information and said re-encrypted information using said encryption key and said new unique key, respectively, and provide said information to said further entity.

2. The system of claim 1, wherein said unique identifier further comprises a palindromic binary representation associated with a sender of said messages.