The invention provides improved methods and apparatus for control using field and control devices that provide a virtual machine environment and that communicate via an IP network. By way of non-limiting example, such field device can be an “intelligent” transmitter or actuator that includes a low power processor, along with a random access memory, a read-only memory, FlashRAM, and a sensor interface. The processor can execute a real-time operating system, as well as a Java virtual machine (JVM). Java byte code executes in the JVM to configure the field device to perform typical process control functions, e.g., for proportional integral derivative (PID) control and signal conditioning. Control networks can include a plurality of such field and control devices interconnected by an IP network, such as an Ethernet.

Methods and apparatus for control using control devices that provide a virtual machine environment and that communicate via an ip network

Connection objects or other such data structures facilitate establishing and configuring connections between objects that model components in a process control system. A first set of data structures (e.g. the object connection type structures) identify valid types for component-to-component pairings and the respective roles of each component in the pairing (e.g., parent or child, source or sink). A second set of data structures (e.g., the parameter connection type structures) supply similar information for parameter-to-parameter connections. Together, these data structures can be used, for example, to validate component-to-component connections suggested by the user and to automatically configure parameter-to-parameter connections. Actual connections, both at the component or parameter level, are reflected using parameter overrides within the parameterized object model—with which the connection objects are constructed.

Process control configuration system with connection validation and configuration

A method and apparatus is provided for automatic protection switching in a ring network by creating a protection domain having a control vlan and protected data vlans and designating a master node and transit nodes connected by a primary port and a secondary port. The master node blocks the secondary port for data vlan traffic until it detects a fault either by notice from a transit node or by polling. When a fault is detected, the master node unblocks the secondary port for data vlan traffic. When the fault is restored, the transit node temporarily blocks the restored port to data vlan traffic thereby preventing a loop. Each time the secondary port is blocked and unblocked, the forwarding databases on all the nodes are flushed.

Ethernet automatic protection switching

A method of designing a telecommunications network, the method comprising the steps of A) for all working demand flows required to be routed in the telecommunications network, finding an initial topology of spans between nodes in the telecommunications network that is sufficient for routing all working demand flows, while attempting to minimize the cost of providing the spans; B) given the initial topology of spans identified in step A, finding a set of additional spans that ensures restorability of working demand flows that are required to be restored in case of failure of any span in the initial topology of spans, while attempting to minimize the cost of providing additional spans; and C) starting with the initial topology of spans and the additional spans identified in step B, finding a final topology of spans between nodes in the telecommunications network that attempts to minimize the total cost of the final topology of spans, while routing all working demand flows and ensuring restorability of working demand flows required to be restored in case of failure of any span in the final topology of spans. A network so designed may be implemented in whole or in part.

http://www.ece.ualberta.ca/~grover/pdf/Grover-Doucette-AOR2001-MeshTopology.pdf

Topological design of survivable mesh-based transport networks

The invention provides, in some aspects, systems for interaction with a control environment that includes controlled equipment along with control devices that monitor and control that controlled equipment. According to some of those aspects, such a system includes first functionality that generates output representing an operational status of the controlled equipment, as well as second functionality that generates output representing an operational of one or more of the control devices. An engine coordinates the first functionality and to the second functionality to generate an operational status of the control environment. A virtual reality environment generates, as a function of that operational status and one or more physical aspects of the control environment, a three-dimensional (“3D”) display of the control environment. The virtual reality environment is responsive to user interaction with one or more input devices to generate the 3D display so as to permit the user to interact with at least one of the control devices and the controlled equipment at least as represented by the 3D display of the control environment. The engine applies to at least one of the first and second functionality indicia of those interactions to discern resulting changes in the operational status of the control environment. It applies indicia of those changes to the virtual reality environment to effect corresponding variation in the 3D display of the control environment—i.e., variation indicative of the resulting change in the control environment.

Systems and methods for immersive interaction with actual and/or simulated facilities for process, environmental and industrial control

A distributed method for creating telecommunications paths in a network, particularly after a span failure The network includes plural distinct nodes interconnected by plural distinct spans, each span having working links and spare links Each node has a digital cross-connect switch for making and breaking connections between adjacent spans forming span pairs at a node At least one of the end nodes of a path to be created broadcasts statelets Each intermediate node between the end nodes broadcasts incoming statelets in a manner that favours use of restoration paths that eliminate the fewest other paths Statelets that have traversed spans with greater spare capacity, considering the number of statelets competing to be broadcast along the spans, are preferentially broadcast

Path restoration of networks

A distributed method creates telecommunications paths in a network, particularly after a span failure. The network includes plural distinct nodes interconnected by plural distinct spans, each span having working links and spare links. Each node has a digital cross-connect switch for making and breaking connections between adjacent spans forming span pairs at a node. At least one of the end nodes of a path to be created broadcasts statelets (Fig 4). Each intermediate node between the end nodes broadcasts incoming statelets in a manner that favours use of restoration paths that eliminate the fewest other paths. Statelets that have traversed spans with greater spare capacity, considering the number of statelets competing to be broadcast along the spans, are preferentially broadcast.

Doherty Lance

Papers

Path restoration of networks

Restoring failed telecoms. links using software agents