Patents by Inventor William T. Haggerty

William T. Haggerty 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).

  • Patent number: 6449279
    Abstract: A method and apparatus are provided for connection-oriented switching in a communications network wherein a pre-established path is established between a select pair of an ingress switch and an egress switch. The use of pre-established paths enables a reduction in the total number of connections required inside the switch cloud, reduces the CPU load on trunk switches, and shortens the time for connection setup. In the embodiment described, the DA/SA fields of a MAC frame data packet are replaced with a “virtual path”, which identifies the pre-established path between the ingress and egress switches. A “virtual circuit” is provided in another field of the modified packet which specifies the out-port and out-header on the egress switch for demultiplexing the modified packet upon receipt at the egress switch. The virtual circuit is exchanged between the ingress and egress switches at connection setup.
    Type: Grant
    Filed: November 20, 2000
    Date of Patent: September 10, 2002
    Assignee: Enterasys Networks, Inc.
    Inventors: David Belser, Richard Bussiere, Jeff Cioli, Brendan Fee, William T. Haggerty
  • Publication number: 20020029288
    Abstract: Apparatus and method wherein multiple router interfaces are assigned the same IP network address, creating an IP work group. This enhances host mobility by allowing, in one embodiment, a host to be relocated anywhere in the work group without requiring reconfiguration of the host. As a further option, host address ranges may be specified (i.e., locked) to designated interfaces of the work group, to enhance security by restricting the allowed host mobility within the work group. An additional advantage is a reduced consumption of network and subnet addresses, because now a single address is used for several physical networks.
    Type: Application
    Filed: June 15, 2001
    Publication date: March 7, 2002
    Inventors: Kurt A. Dobbins, David L. Cullerot, Stephen H. Negus, William T. Haggerty
  • Patent number: 6331983
    Abstract: Method and apparatus for establishing connections in a switch-based communications network for multicast traffic. A source receives a multicast packet on an access port from a source host, determines a group address in the multicast packet, and composes and sends a “sender present” message to other switches on its network ports. The receiving switches determine whether a local host wishes to join the group and if so, send a map message back toward the source switch on a predetermined path between the receiving switch and the source switch. A map message may terminate at a switch on the path that already has a connection for this group/source pair, and join into this connection as an additional output port. In this manner, a “signal out, connect back” method is provided for establishing a connection path from the sender to multiple receivers.
    Type: Grant
    Filed: May 6, 1997
    Date of Patent: December 18, 2001
    Assignee: Enterasys Networks, Inc.
    Inventors: William T. Haggerty, Phillip Andlauer, Stephen H. Negus
  • Patent number: 6249820
    Abstract: Apparatus and method wherein multiple router interfaces are assigned the same IP network address, creating an IP work group. This enhances host mobility by allowing, in one embodiment, a host to be relocated anywhere in the work group without requiring reconfiguration of the host. As a further option, host address ranges may be specified (i.e., locked) to designated interfaces of the work group, to enhance security by restricting the allowed host mobility within the work group. An additional advantage is a reduced consumption of network and subnet addresses, because now a single address is used for several physical networks.
    Type: Grant
    Filed: May 6, 1998
    Date of Patent: June 19, 2001
    Assignee: Cabletron Systems, Inc.
    Inventors: Kurt A. Dobbins, David L. Cullerot, Stephen H. Negus, William T. Haggerty
  • Patent number: 6151324
    Abstract: A method and apparatus are provided for connection-oriented switching in a communications network wherein a pre-established path is established between a select pair of an ingress switch and an egress switch. The use of pre-established paths enables a reduction in the total number of connections required inside the switch cloud, reduces the CPU load on trunk switches, and shortens the time for connection setup. In the embodiment described, the DA/SA fields of a MAC frame data packet are replaced with a "virtual path", which identifies the pre-established path between the ingress and egress switches. A "virtual circuit" is provided in another field of the modified packet which specifies the out-port and out-header on the egress switch for demultiplexing the modified packet upon receipt at the egress switch. The virtual circuit is exchanged between the ingress and egress switches at connection setup. The virtual path is assumed to already be in place, and known to both switches, prior to connection setup.
    Type: Grant
    Filed: June 3, 1996
    Date of Patent: November 21, 2000
    Assignee: Cabletron Systems, Inc.
    Inventors: David Belser, Richard Bussiere, Jeff Cioli, Brendan Fee, William T. Haggerty
  • Patent number: 5751971
    Abstract: Apparatus and method wherein multiple router interfaces are assigned the same IP network address, creating an IP work group. This enhances host mobility by allowing, in one embodiment, a host to be relocated anywhere in the work group without requiring reconfiguration of the host. As a further option, host address ranges may be specified (i.e., locked) to designated interfaces of the work group, to enhance security by restricting the allowed host mobility within the work group. An additional advantage is a reduced consumption of network and subnet addresses, because now a single address is used for several physical networks.
    Type: Grant
    Filed: July 12, 1995
    Date of Patent: May 12, 1998
    Assignee: Cabletron Systems, Inc.
    Inventors: Kurt A. Dobbins, David L. Cullerot, Stephen H. Negus, William T. Haggerty
  • Patent number: 4751669
    Abstract: A videotex decoder apparatus which, in various aspects, displays a status line to indicate when connect charges are occurring; overlays menus over displayed videotex frames with portions of the displayed frames remaining visible; provides easily called log-on procedures; retrieves remote information frames by user-specified keywords names; prints information frames in selectable different overall sizes; provides selectable different character sets for display; is table-driven; is structured to include a device independent decoder and device dependent drivers; includes a controller which feeds bytes to the decoder for decoding without regard to the protocol-dependent information content of those bytes; and uses an added frame header on stored frames to indicate the videotex protocol for decoding the frames.
    Type: Grant
    Filed: April 4, 1985
    Date of Patent: June 14, 1988
    Assignee: Wang Laboratories, Inc.
    Inventors: Samuel P. Sturgis, William T. Haggerty, Barbara C. Sangster
  • Patent number: 4703318
    Abstract: Forming a character-based monochromatic image from a digital representation of a color image by (1) forming a character-based representation of the color image in which a plurality of color characters each describe the background and foreground color within a defined area of the color image, (2) providing a plurality of color pattern masks each corresponding to a color in the color image and comprised of a pattern of light and dark dots capable of providing, in the monochromatic image, visual discrimination between areas of different color, (3) transforming the color characters to monochromatic characters by replacing the background and foreground color of each color character with the corresponding pattern of light and dark dots, and (4) displaying the monochromatic characters on a character-based output device (e.g., a CRT display driven by a character-based controller).
    Type: Grant
    Filed: April 16, 1985
    Date of Patent: October 27, 1987
    Assignee: Wang Laboratories, Inc.
    Inventor: William T. Haggerty
  • Patent number: 4688031
    Abstract: A color to monochromatic image transformation which transforms each color area of the original image into a corresponding area of a monochromatic image having a particular pattern of `light` and `dark` dots corresponding to and representing the original color of the area. The dot patterns are selected to provide both gray scale representations of the original colors and differing textural appearances for each color, so as to maximize the discrimination between the areas of the monochromatic image. The monochromatic dot patterns do not necessarily correspond exactly to the colors or gray scale values of the original colors, but are selected to provide visual impressions analogous to the visual impressions provided by the corresponding original colors.
    Type: Grant
    Filed: March 30, 1984
    Date of Patent: August 18, 1987
    Assignee: Wang Laboratories, Inc.
    Inventor: William T. Haggerty