Patents by Inventor Thomas Woo

Thomas Woo 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: 20060230450
    Abstract: Wireless state information and user/network profiling are used to detect and prevent Denial of Service attacks.
    Type: Application
    Filed: March 31, 2005
    Publication date: October 12, 2006
    Inventors: Tian Bu, Samphel Norden, Thomas Woo
  • Publication number: 20060092976
    Abstract: An embodiment of the exemplary SoftRouter architecture includes two physically separate networks, a control plane network and a data plane network. The data plane network is one physical network for the data traffic, while the control plane network is another physical network for the control traffic. The topology of the data plane network is made up of interconnected forwarding elements (FEs). The topology of the control plane network is made up interconnected control elements (CEs). This physical independence of the control plane network from the data plane network provides for a secure mechanism to communicate among the CEs in the control plane network. In addition, this physical independence provides improved reliability and improved scalability, when compared to the traditional router architecture, where control plane message are in-band with the data plane.
    Type: Application
    Filed: June 8, 2005
    Publication date: May 4, 2006
    Inventors: Tirunell Lakshman, Krishan Sabnani, Thomas Woo
  • Publication number: 20060092935
    Abstract: A network architecture includes one or more feature servers and control servers in a control plane that is logically separate from a data plane that includes forwarding elements. Feature servers facilitate adding network-based functionality in a centralized way that is has better scalability than the traditional router architecture. Some examples of network-based functionality are voice over IP, enhancing QoS support, scaling BGP route reflectors, network-based VPN support, scaling mobile IP support, introducing IPv6 into existing and future networks, and enhancing end-to-end network security. Feature servers remove complexity from routers, allow functions to be implemented on a standard-off-the-shelf server platform, facilitate easy introduction of value-added functions, and scale well.
    Type: Application
    Filed: June 8, 2005
    Publication date: May 4, 2006
    Inventors: Tirunell Lakshman, Krishan Sabnani, Thomas Woo
  • Publication number: 20060092940
    Abstract: A SoftRouter architecture deconstructs routers by separating the control entities of a router from its forwarding components, enabling dynamic binding between them. In the SoftRouter architecture, control plane functions are aggregated and implemented on a few smart servers which control forwarding elements that are multiple network hops away. A dynamic binding protocol performs network-wide control plane failovers. Network stability is improved by aggregating and remotely hosting routing protocols, such as OSPF and BGP. This results in faster convergence, lower protocol messages processed, and fewer route changes following a failure. The SoftRouter architecture includes a few smart control entities that manage a large number of forwarding elements to provide greater support for network-wide control. In the SoftRouter architecture, routing protocols operate remotely at a control element and control one or more forwarding elements by downloading the forwarding tables, etc. into the forwarding elements.
    Type: Application
    Filed: June 8, 2005
    Publication date: May 4, 2006
    Inventors: Furquan Ansari, Martin Havemann, Tirunell Lakshman, Thyagarajan Nandagopal, Ramachandran Ramjee, Thomas Woo
  • Publication number: 20060092857
    Abstract: A dynamic binding protocol has three tasks that run in parallel: discovery, association, and operation. During discovery, control elements (CEs) and forwarding elements (FEs) learn about immediate neighbors and CEs in a SoftRouter network that has separate control and data planes. During association, FEs associate with CEs and are configured with basic parameters, such as IP interface addresses, hostnames, and the like. During operation, failover and packet tunneling between CEs and FEs is handled.
    Type: Application
    Filed: June 8, 2005
    Publication date: May 4, 2006
    Inventors: Furquan Ansari, Martin Havemann, Tirunell Lakshman, Thyagarajan Nandagopal, Ramachandran Ramjee, Thomas Woo
  • Publication number: 20060092974
    Abstract: The SoftRouter architecture separates the implementation of control plane functions from packet forwarding functions. In this architecture, all control plane functions are implemented on general purpose servers called the control elements (CEs) that may be multiple hops away from the forwarding elements (FEs). A network element (NE) or a router is formed using dynamic binding between the CEs and the FEs. The flexibility of the SoftRouter architecture over conventional routers with collocated and tightly integrated control and forwarding functions results in increased reliability, increased scalability, increased security, ease of adding new functionality, and decreased cost.
    Type: Application
    Filed: June 8, 2005
    Publication date: May 4, 2006
    Inventors: Tirunell Lakshman, Thyagarajan Nandagopal, Ramachandran Ramjee, Krishan Sabnani, Thomas Woo
  • Publication number: 20060092975
    Abstract: The SoftRouter architecture separates the implementation of control plane functions from packet forwarding functions. In this architecture, all control plane functions are implemented on general purpose servers called the control elements (CEs) that may be multiple hops away from the forwarding elements (FEs). A network element (NE) or a router is formed using dynamic binding between the CEs and the FEs. There is a protocol failover mechanism for handling failovers initiated by FEs to transfer control from one CE to another CE.
    Type: Application
    Filed: June 8, 2005
    Publication date: May 4, 2006
    Inventors: Furquan Ansari, Tirunell Lakshman, Thyagarajan Nandagopal, Ramachandran Ramjee, Thomas Woo
  • Publication number: 20050286664
    Abstract: An apparatus for mixing audio signals in a voice-over-IP teleconferencing environment comprises a preprocessor, a mixing controller, and a mixing processor. The preprocessor is divided into a media parameter estimator and a media preprocessor. The media parameter estimator estimates signal parameters such as signal-to-noise ratios, energy levels, and voice activity (i.e., the presence or absence of voice in the signal), which are used to control how different channels are mixed. The media preprocessor employs signal processing algorithms such as silence suppression, automatic gain control, and noise reduction, so that the quality of the incoming voice streams is optimized. Based on a function of the estimated signal parameters, the mixing controller specifies a particular mixing strategy and the mixing processor mixes the preprocessed voice streams according the strategy provided by the controller.
    Type: Application
    Filed: June 24, 2004
    Publication date: December 29, 2005
    Inventors: Jingdong Chen, Yiteng Huang, Thomas Woo
  • Publication number: 20050221839
    Abstract: A base station controller (BSC) of a radio or wireless telecommunications network base station includes a director. A BSC includes multiple central processing units (CPUs), with each CPU running a call-processing application for one or more connections. The director is a logical entity that intercepts wireless call-setup signaling and assigns each corresponding connection to a CPU according to a centralized load-balancing algorithm. The centralized load-balancing algorithm distributes connections to less loaded CPUs to i) prevent individual CPUs from overloading, ii) utilize otherwise unused system resources, and iii) increase overall system performance. The director hosts cell components that manage code division multiple access (CDMA) downlink spreading codes for a base station, providing centralized allocation of spreading codes by the base station.
    Type: Application
    Filed: March 31, 2004
    Publication date: October 6, 2005
    Inventors: Mun-Choon Chan, Martin Havemann, Ramachandran Ramjee, Sandra Thuel, Thomas Woo
  • Publication number: 20050165901
    Abstract: Network architecture and related methods for maintaining traffic flow between clients and an end-server during a Denial of Service (DoS) attack are described herein. The network architecture includes a set of overlay nodes coupled between clients and a server. Each overlay node is able to rank and probe other nodes for purposes of selecting a best path for routing traffic to the end-server to resist a denial of service of attack. Probing is performed to detect overlay nodes having better performance based on one or more performance metrics (i.e., load, jitter, latency, loss rate). For instance, in one implementation probing detects lightly loaded overlay paths for purposes of routing traffic to the end-server, so as to maintain connectivity between the end-server and clients even under DoS attacks.
    Type: Application
    Filed: January 22, 2004
    Publication date: July 28, 2005
    Inventors: Tian Bu, Samphel Norden, Thomas Woo
  • Patent number: 5485219
    Abstract: A central station monitors television broadcasts and issues control and informational broadcasts to receivers located in the homes of users. The information broadcasts include a TV program schedule table and recorder control data. In response to the control broadcasts, processors receiving the broadcast will pause and resume recording of the identified broadcasts. A user can phone into the central station to have the user's recorder programmed to record a particular broadcast.
    Type: Grant
    Filed: April 18, 1994
    Date of Patent: January 16, 1996
    Assignee: Depromax Limited
    Inventor: Thomas Woo
  • Patent number: 5473200
    Abstract: A theft prevention device that includes a digital control unit and digital receiving units. These digital components form a control system along with existing peripheral components. The control system utilizes a signal network where signals are transmitted and received on the existing wiring or through the air between the digital components. The components of the anti-theft device operate in either an armed or disarmed state, and the system automatically arms whenever the ignition key is turned from on to off. If the system is in a vehicle and the vehicle is started without disarming the system first, each component becomes active after its programmed time delay has elapsed. A unique code, generated by the digital control unit, is passed through alarm system's signal network during the disarmed state such that the digital components in the theft prevention device becomes active and perform their respective functions even if the power supply is cut in the armed state.
    Type: Grant
    Filed: October 8, 1993
    Date of Patent: December 5, 1995
    Assignee: Depromax Limited
    Inventor: Thomas Woo