Patents by Inventor George Tsirtsis

George Tsirtsis has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20040203711
    Abstract: Methods and apparatus for storing, manipulating, retrieving, and forwarding state, e.g., context and other information, used to support communications sessions with one or more end nodes, e.g., mobile devices, are described. Various features are directed to a mobile node controlling the transfer of state from a first access node to a second access node during a handoff operation thereby eliminating any need for state transfer messages to be transmitted between the second access node and the first access node during handoff. Other features of the invention are directed to the use of a core network node to store state information. State information stored in the core node can be accessed and used by access nodes in cases where a mobile node does not send a state transfer message during a handoff, e.g., because communication with the first access node is lost or because such messages are not supported.
    Type: Application
    Filed: February 18, 2003
    Publication date: October 14, 2004
    Inventors: Alan O'Neill, M. Scott Corson, George Tsirtsis, Vincent Park
  • Publication number: 20040148428
    Abstract: Methods and apparatus for supporting network layer protocol version independent mobility management are described. In accordance with the present invention, the signaling method used to set-up the redirection (encapsulation or tunnel) is separated from the type of redirection being set-up. Through the use of a Protocol Independent Mobility Management Protocol and/or modules for implementing one or more aspects of the Protocol of the present Invention, Mobile IPv4 and IPv6 may run on top of any version of the network layer and can set-up tunnels of any network layer version over any other network layer version. Various features of the invention are used to establish tunnels which are capable of being used to commutate IPv4 and/or IPv6 packets. Other features are directed to storing and using state information which allows IPv4 and/or IPv6 packets to be sent through a tunnel established using IPv4 or IPv6 type signaling.
    Type: Application
    Filed: February 25, 2003
    Publication date: July 29, 2004
    Inventor: George Tsirtsis
  • Publication number: 20040073786
    Abstract: Traditional circuit-switched cellular systems first authorise the mobile terminal and then secure the wireless access link between the cellular radio access network and the users mobile terminal. The IP protocol is then allowed to run as an application over that access link. Internet access systems traditionally use an unsecured access link and use IP messaging to authorise the Mobile Node (IP host) on the mobile terminal, and the resulting communications. Cellular systems therefore authorise and secure at layer 2 (with respect to IP) whilst Internet systems authorise and secure at layer 3 in general. An Internet compliant cellular system needs to potentially authorise and secure both the MACand IP layers and traditionally this is done with two phases using two independent AAA systems (Authentication, Authorisation and Accounting) with L3 following L2 which results in unnecessary complexity, cost and delay when gaining access to a communications network.
    Type: Application
    Filed: May 9, 2003
    Publication date: April 15, 2004
    Inventors: Alan O'Neill, Michaela Vanderveen, George Tsirtsis, Vincent Park
  • Publication number: 20030224758
    Abstract: Methods and apparatus for improving tunneling techniques and reducing packet loss in mobile communications systems are described. The methods and apparatus are well suited for use with Mobile IP and can facilitate handoff operations. A mobile node establishes multiple tunnels, representing downlinks, from the mobile node perspective. The different downlink tunnels are through different access nodes but terminate at the same home agent. The mobile node maintains, at most, a single uplink tunnel at any given time with the home agent. Tunnels representing uplinks and downlinks are managed independently. Thus, each of the uplink and downlink tunnels can have different lifetimes and can be created/removed independently allowing for flexibility in handoff operations.
    Type: Application
    Filed: April 14, 2003
    Publication date: December 4, 2003
    Inventors: Alan O'Neill, George Tsirtsis, Matthew Impett, Vincent Park
  • Publication number: 20030137961
    Abstract: Session signaling register message transmission methods and apparatus well suited for use in a communication system which supports mobile nodes capable of moving between domains and access nodes in a domain are described. Broadcasting of session signaling register messages is supported to reduce the number of registration messages which need to be transmitted between a mobile node and an access node. A paging and location server is used to reduce the number of session signaling register messages transmitted between domains. A visiting node registers with a paging and location server. The session signaling address of the paging and location server being used by a visiting mobile node is registered with the visiting node's home session signaling server. As the visiting node moves between access nodes in the visited domain the paging and location server it uses remains the same eliminating the need to update the home session signaling servers.
    Type: Application
    Filed: December 18, 2002
    Publication date: July 24, 2003
    Inventors: George Tsirtsis, Alan O'Neill
  • Publication number: 20030137962
    Abstract: Session signaling register message transmission methods and apparatus well suited for use in a communication system which supports mobile nodes capable of moving between domains and access nodes in a domain are described. Broadcasting of session signaling register messages is supported to reduce the number of registration messages which need to be transmitted between a mobile node and an access node. A paging and location server is used to reduce the number of session signaling register messages transmitted between domains. A visiting node registers with a paging and location server. The session signaling address of the paging and location server being used by a visiting mobile node is registered with the visiting node's home session signaling server. As the visiting node moves between access nodes in the visited domain the paging and location server it uses remains the same eliminating the need to update the home session signaling servers.
    Type: Application
    Filed: December 18, 2002
    Publication date: July 24, 2003
    Inventors: George Tsirtsis, Alan O'Neill
  • Publication number: 20030003938
    Abstract: Group communications methods and apparatus are described. In particular, methods for granting a mobile device access to a communications resource, e.g., the right to transmit data, associated with a group are described. User requests for the communications resource are suppressed by the corresponding mobile device, for periods during which the communications resource has been granted to another mobile device. A mobile device may store a suppressed user request so that a resource request signal may be transmitted after the communications resource has been released by the mobile device that was previously granted the resource. In this manner requests that cannot be granted are not transmitted, increasing communications efficiency as compared to systems where requests are not suppressed at the mobile devices. A priority scheme is used in some embodiments to determine whether or not a request should be suppressed while another device has been granted the communications resource.
    Type: Application
    Filed: June 26, 2002
    Publication date: January 2, 2003
    Inventors: Alan O'Neill, M. Scott Corson, Vincent Park, Michaela Vanderveen, George Tsirtsis
  • Publication number: 20020191593
    Abstract: A mobile communications system that uses IP packets to transmit data between end nodes, such as mobile devices, is described. In order to facilitate session establishment, maintenance, security, and handoff operations, access nodes through which end nodes communicate with one another include a session signaling server module and a mobility agent module. The session signaling server module may be implemented as a SIP server while the mobility agent module may be implemented using Mobil IP signaling. The mobility agent and SIP server within an access node are identified using a single shared identifier, IP address. The same security method and common secret may be used to provide security with regard to both mobile IP messages and SIP messages. Sessions admission decisions and resource allocation for admitted sessions can also take place internally to the access node of this invention without need for signaling to external elements.
    Type: Application
    Filed: June 11, 2002
    Publication date: December 19, 2002
    Inventors: Alan O'Neill, M. Scott Corson, Vincent Park, George Tsirtsis