Abstract: A method of transmitting packets over a network includes steps of partitioning a packet delivery schedule into discrete time slots; transmitting a plurality of test packets from a first endpoint on the network to an intended recipient in the network using different time slots; evaluating the reliability of the network to transmit the plurality of test packets in each time slot; and selecting one or more time slots in the delivery schedule according to the evaluation step.

Abstract: A method of transmitting packets over a network includes steps of transmitting a first plurality of test packets during a first plurality of time locations that are coarsely spaced apart in time; determining which of the first plurality of time locations corresponds to favorable network traffic conditions; transmitting a second plurality of test packets over the network during a second plurality of time locations that are finely spaced apart in time, wherein the second plurality of time locations are selected on the basis of favorable network traffic conditions; determining which of the second plurality of time locations corresponds to favorable network traffic conditions; and transmitting data packets over the network using one or more favorable time locations determined by the finely spaced test packets. The method can be used to “zero in” on congested network periods by detecting differences in packet latencies among test packets.

Abstract: A method of transmitting packets over a network includes steps of partitioning a packet delivery schedule into discrete time slots; transmitting a plurality of test packets from a first endpoint on the network to an intended recipient in the network using different time slots; evaluating the reliability of the network to transmit the plurality of test packets in each time slot; and selecting one or more time slots in the delivery schedule according to the evaluation step.

Abstract: The invention provides a method for transmitting packets in a network from multiple data sources, by eliminating contention among local transmitters in the network. A device comprises a CPU and other modules that accept input from various signal sources. The device processes the signals from the various sources, converts the signals to data and then outputs the signal data in the form of packets which it sends via a LAN and/or WAN, thus avoiding contention on the LAN. The invention may initiate and receive connections via the LAN or WAN and begin transmitting over the LAN or WAN at agreed-upon rates without contention.

Abstract: A network connection device bridges a first network that uses a first packet delivery scheduling scheme and a second network that uses a different packet delivery scheduling scheme. The network connection device translates a request to communicate over the first network into a request to communicate over the second network, thus bridging the two networks. A negotiated packet delivery scheduling scheme permits endpoints to negotiate scheduled delivery times for packets, while an empirically determined packet delivery scheme tests various time interval locations in a network to determine favorable time locations for transmission. The two protocols are bridged by finding compatible overlaps between time interval locations in the two networks. This can provide error-free delivery with low jitter among packets.

Abstract: A method of transmitting packets over a network includes steps of transmitting a first plurality of test packets during a first plurality of time locations that are coarsely spaced apart in time; determining which of the first plurality of time locations corresponds to favorable network traffic conditions; transmitting a second plurality of test packets over the network during a second plurality of time locations that are finely spaced apart in time, wherein the second plurality of time locations are selected on the basis of favorable network traffic conditions; determining which of the second plurality of time locations corresponds to favorable network traffic conditions; and transmitting data packets over the network using one or more favorable time locations determined by the finely spaced test packets. The method can be used to “zero in” on congested network periods by detecting differences in packet latencies among test packets.

Abstract: A network connection device bridges a first network that uses a negotiated packet delivery scheduling scheme and a second network that uses an empirically determined packet delivery scheduling scheme. The network connection device translates a request to communicate over the first network into a request to communicate over the second network, thus bridging the two networks. The negotiated packet delivery scheduling scheme permits endpoints to negotiate scheduled delivery times for packets, while the empirically determined packet delivery scheme tests various time interval locations in a network to determine favorable time locations for transmission. The two protocols are bridged by finding compatible overlaps between time interval locations in the two networks. This can provide error-free delivery with low jitter among packets.

Abstract: A method of transmitting packets over a network includes steps of partitioning a transmission interval into discrete time slots and reaching agreement between a transmitting node and receiving node as to when the transmitting node will transmit packets. The intended receiving node sends a reception map to the transmitter indicating time slots that have not yet been allocated. The transmitter proposes a delivery schedule including time slots that it will use for transmission. After agreement by the receiving node, the transmitter transmits packets according to the agreed-upon schedule. Other transmitters can similar arrange to transmit during time slots not already allocated for the receiving node.

Abstract: An apparatus and method for switching data packet flows by assigning schedules to guaranteed delay and bandwidth traffic. Scheduled bandwidth is subtracted from the available bandwidth, and the remaining unscheduled bandwidth is available for standard “best-efforts” packet transmissions, or other guaranteed packet flows. Guaranteed bandwidth is assigned on a schedule basis, and packet flows are assigned schedules which are mutually acceptable to both transmitters and receivers. Flows transmit and expect to receive packets in accordance with their assigned schedules. Schedules are negotiated between packet transmitter applications and packet receiver applications. During scheduled periods, packets sent by the packet transmitter are directly and immediately forwarded to the assigned packet receiver.

Abstract: A LAN telephone which makes voice telephone calls over a local area network (LAN) data network. Acoustic voice sounds are digitally encoded and transmitted as data, over the LAN. The disclosed telephone simultaneously receives LAN data packets and decodes them, translating the data into acoustic audio voice sounds. All communications with the network occur through the use of the LAN, including data for call control and for voice signals. The disclosed LAN telephone uses a packet scheduling technique to prevent packet collision, delay or loss. The scheduling technique relies on time of transmission and arrival to switch packets. Additionally, the disclosed LAN telephone is operable to receive power from a data switch, using LAN wiring. The instrument further includes a means for attaching peripheral devices through an electronic interface system, as well as an internal system for allowing the telephone to be moved, from one connection to another, without changing the telephone number.

Abstract: A method and apparatus for creating and using multiple redundant paths between endpoints in a scheduled communication network, and for sending copies of data down each path. A path calculation is made for one or more redundant paths between designated branch and merge points in a network using scheduled switch/routers, and duplicate packets are transmitted along each path to the merge point. The first packet received among the configured paths at the merge point is forwarded to a resulting data stream and the later (duplicate) copies from other paths are discarded. Path itineraries are configured to maintain temporal packet sequence in the resulting stream. Path status is monitored and additional paths can be substituted if a path has an outage. Alternatively, multiple divergent paths can be configured, and duplicate packets transmitted along each path, where at least one path delivers data between end points, and a monitoring path also transmits copies of the data to an alternate location.

Abstract: A system for guaranteeing bandwidth for transmitting data in a network. A path generation engine determines a data paths across a network according to preselected criteria. A scheduling engine determines schedule appointments for data packets to traverse each link in the network including compensation for transmission delays and switch latencies. Scheduling data is communicated to schedule-aware switches and endpoints so that appointment times are reserved for transmission of the scheduled data packets. Real-time transmission of data can be guaranteed in both directions along the transmission path.

Abstract: A system for providing power to telephone handsets and other appliances that are connected to a LAN switch. Telephone handsets with built-in Ethernet interfaces can be used to create an enterprise voice communications network which emulates the functions of a standard voice private branch exchange (PBX) switch. The disclosed LAN switch advantageously provides power directly to LAN telephone instruments within the system. The disclosed system may include a means for adding a power system to an existing LAN switch so that remote telephone handsets can receive power from a central location. Alternatively, power equipment may be integrated into a LAN switch itself. The primary benefit of a central power system for Ethernet appliances is that is more convenient to provide back-up power, so that the attached appliances can continue to operate in the event of a power failure.

Abstract: An apparatus and method for switching data packet flows by assigning schedules to guaranteed delay and bandwidth traffic. Scheduled bandwidth is subtracted from the available bandwidth, and the remaining unscheduled bandwidth is available for standard “best-efforts” packet transmissions, or other guaranteed packet flows. Guaranteed bandwidth is assigned on a schedule basis, and packet flows are assigned schedules which are mutually acceptable to both transmitters and receivers. Flows transmit and expect to receive packets in accordance with their assigned schedules. Schedules are negotiated between packet transmitter applications and packet receiver applications. During scheduled periods, packets sent by the packet transmitter are directly and immediately forwarded to the assigned packet receiver.

Abstract: An external speakerphone accessory system for a telephone, such as a LAN telephone, which enables the telephone user to place the speakerphone in a location that is convenient for multiple users, and which is not necessarily co-located with the attached telephone itself. The speakerphone accessory obtains all of its power, audio, and control signals from an attached telephone unit through a modified Universal Serial Bus (USB) interface, and includes a power supply system which enables it to obtain a relatively high power level from the telephone to which it is attached. The speakerphone accessory uses a delay detected between when an audio signal is received at a left hand side microphone and when that audio signal is received at a corresponding right hand side microphone to define zones of maximum sensitivity with regard to users of the speakerphone accessory.

Abstract: A LAN telephone which makes voice telephone calls over a local area network (LAN) data network. Acoustic voice sounds are digitally encoded and transmitted as data, over the LAN. The disclosed telephone simultaneously receives LAN data packets and decodes them, translating the data into acoustic audio voice sounds. All communications with the network occur through the use of the LAN, including data for call control and for voice signals. The disclosed LAN telephone uses a packet scheduling technique to prevent packet collision, delay or loss. The scheduling technique relies on time of transmission and arrival to switch packets. Additionally, the disclosed LAN telephone is operable to receive power from a data switch, using LAN wiring. The instrument further includes a means for attaching peripheral devices through an electronic interface system, as well as an internal system for allowing the telephone to be moved, from one connection to another, without changing the telephone number.

Abstract: An improved shielding assembly for a circuit board. This assembly is formed by providing a substantially flat piece of metal that will be used to form a shield assembly. A template is obtained indicating locations of folds and tabs. The folds are at locations that will enable the tabs to be located in the holes on the circuit board. The template is used to etch grooves and to etch tabs. This can be used to form a shielding assembly.

Abstract: An improved shielding assembly for a circuit board. The assembly includes a multi-layer circuit board, each layer of which has ground planes around the perimeter thereof. An edge plating on the circuit board connects the ground planes to one another. A number of tab holes are also in the board, and the shielding assembly is formed as a conductive box which is connected to the tab holes. A shielded area is formed within the shielding assembly. The shielding assembly is preferably formed by etching fold locations and folding, and by etching tabs to be formed.

Abstract: A shielded print head assembly has a plurality of pieces that are self-aligned with one another. A base forms a ground plane, and includes a registry structure thereon which is preferably a pin extending above a top surface thereof. A circuit board is aligned by connecting inner surfaces of the circuit board around the pin to precisely locate a connector of the circuit board. A print head is located adjacent to the circuit board such that its connector is exactly adjacent to connector of the circuit board. An innerface connector is then used to connect between the circuit board connector and the print head connector, the interface connector being completely shielded by a cover. The interface connector is also held in self-alignment by the registry structure. The interface connector also has a top surface defining an insulation area, coupled against the cover which forms a ground plane. In this way, a shielded and self-aligned multi-piece print head is formed.