Abstract: A system for assessing energy usage reads read at least one computer-aided design (CAD) file relating to the architecture of a facility and extracts information from the CAD file for use in determining static energy characteristics corresponding to the architecture of the facility, acquires information for use in determining dynamic energy characteristics of the facility, and calculates a predicted energy usage of the facility based at least in part on the static and dynamic energy characteristics. The system further acquires data from at least one sensor configured to measure actual energy usage of the facility in real-time and calculates the actual energy usage of the facility. When the actual energy usage exceeds the predicted energy usage, the system transmits an alert to a user and determines corrective measures to reduce energy usage.

Abstract: A system for analyzing energy usage measures one or more parameters indicative of energy usage for a plurality of sub-circuits, where the sampling rate for the measuring is substantially continuous, and automatically transmits information related to at least one of the measured parameters at a rate that enables monitoring of current energy usage. The system further detects a significant change in a measured parameter, determines whether the significant change in the measured parameter is caused by a change in energy usage, and automatically transmits information related to the significant change in the measured parameter caused by the change in energy usage after detecting the significant change.

Abstract: A repeater provides an efficient interconnection of an IEEE 802.3 10 Mb/s network with an IEEE 802.3 100 Mb/s network using minimal buffering. The repeater includes a filter that selectively outputs a data packet, received from the 100 Mb/s network, to the 10 Mb/s network based on the destination address in the received data packet. Specifically, the filter passes all data packets in the 10 Mb/s domain to the 100 Mb/s domain. The filter selectively passes the data packet from the 100 Mb/s domain to the 10 Mb/s domain by determining if the received data packet includes a destination address value that specifies transmission of the data packet to the 10 Mb/s network. If the destination address value does not specify a multicast value or an address of a network node in the 10 Mb/s network, the filter discards the data packet.

Abstract: A buffered distributor having a plurality of network ports serving respective network nodes includes a distribution core having a filter for selectively supplying a data packet to a selected network port based on the destination address of the received data packet relative to the network address of the network node corresponding to the selected network port. The buffered distributor distributes the received data packet to all network ports. Each network port includes a transmit buffer that loads the distributed data packet in response to an enable signal from the distribution core. The filter logic outputs a filter signal that prevents generation of the enable signal for a selected transmit buffer if a review of the destination address indicates the distributed data packet is not relevant to the corresponding network port.

Abstract: A network station transmitting on a half-duplex Ethernet (802.3) half-duplex media includes a delay credit counter that tracks a delay interval after transmission of a data packet to ensure the network station operates according to an assigned transmission rate. The delay credit counter is decremented by a delay count calculated based on the number of transmitted data bytes and the assigned rate of the network station, and incremented during non-transmitting (i.e., idle) intervals by the network station. The network station defers from transmitting on the half-duplex network media until the delay credit counter has a counter value greater than or equal to zero, resulting in a reduced number of collisions between network stations.

Abstract: A buffered distributor (i.e., a full-duplex repeater) having receive buffers for respective network ports calculates pause frames based on the size of stored data packets that need to be output by the repeater core according to a round robin sequence before congestion in an identified receive buffer is eliminated. The distribution core within the buffered distributor includes a linked list register that stores the determined links of received data packets for each network port. Upon detecting a congestion condition in one of the receive buffers for a corresponding port, the buffered distributor determines the relative position of the congested port within the round robin sequence, and calculates the pause interval based on the length of the data packets that need to be output before congestion is eliminated. The sum of the data packet lengths are compared to an output data rate of the distribution core, as well as switching delays within the core.