Abstract: Hitless Switching provides a method of delivering data to a remote point in a reliable fashion. However, no guarantee or acknowledgement is provided that data has been written to a remote storage device. This is problematic for remote data mirroring. Apparatus and methods are provided to guarantee that data arriving at a remote terminal is correctly stored. Interaction with hitless switching and remote optical mirroring systems are described.

Abstract: The invention provides a method and apparatus for providing hitless protection switching in a synchronous transmission system. A switching apparatus is arranged to receive data signals on at least two transmission paths and to output data from a selected one of said transmission paths. The apparatus is arranged to align the respective received data signals so that a selector mechanism can select between corresponding elements of the received data signals. This arrangement allows hitless switching to be performed since there is no loss or repetition of signal elements when switching occurs. In a preferred embodiment, data in respect of each frame of each data signal is stored and the selector mechanism selects between paths on a frame-by-frame basis by comparing quality information carried by the data signals. This arrangement offers a very low end to end Bit Error Rate (BER) performance.

Abstract: Hitless Switching provides a method of delivering data to a remote point in a reliable fashion. However, no guarantee or acknowledgement is provided that data has been written to a remote storage device. This is problematic for remote data mirroring. Apparatus and methods are provided to guarantee that data arriving at a remote terminal is correctly stored. Interaction with hitless switching and remote optical mirroring systems are described.

Abstract: The invention relates particularly to the switching of an SDH low order VC-3 using a high order switching apparatus, such as an STS switch. A low order VC-3 is aligned with a TU-3 pointer to form a TU-3. The TU-3 is mapped into a high order VC-3 type data structure which, in turn, is aligned with an AU-3 pointer to form an AU-3 type data structure. The AU-3 type data structure is suitable for switching by the high order switch. After switching, the AU-3 type data structure is combined with similar AU-3 type data structures and converted into an AU-4 suitable for transmission across an SDH/SONET network. Advantageously, the arrangement is such that each AU-3 pointer has the same fixed value. Hence, conversion to an AU-4 is achieved by a fixed pointer replacement operation.

Abstract: This invention relates to improvements in and relating to antimicrobial compositions. More particularly, it relates to antimicrobial compositions comprising or including a mixture of oils of melaleuca alternifolia and leptospermum scoparium and/or fractions or dilutions of same. A method of producing the composition is also claimed, as are methods of producing compositions which target particular microbes.

Abstract: The invention provides a method and apparatus for providing hitless protection switching in a transmission systems which support a standardized implementation of virtual concatenation. A switching apparatus is arranged to receive data signals on at least two transmission paths and to output data from a selected one of said transmission paths. The apparatus is arranged to align the respective received data signals so that a selector mechanism can select between corresponding elements of the received data signals. This arrangement allows hitless switching to be performed since there is no loss or repetition of signal elements when switching occurs. In a preferred embodiment, data in respect of each frame of each data signal is stored and the selector mechanism selects between paths on a frame-by-frame basis by comparing quality information carried by the data signals. This arrangement offers a very low end to end Bit Error Rate (BER) performance.

Abstract: The invention provides a method and apparatus for providing hitless protection switching in a synchronous transmission system. A switching apparatus is arranged to receive data signals on at least two transmission paths and to output data from a selected one of said transmission paths. The apparatus is arranged to align the respective received data signals so that a selector mechanism can select between corresponding elements of the received data signals. This arrangement allows hitless switching to be performed since there is no loss or repetition of signal elements when switching occurs. In a preferred embodiment, data in respect of each frame of each data signal is stored and the selector mechanism selects between paths on a frame-by-frame basis by comparing quality information carried by the data signals. This arrangement offers a very low end to end Bit Error Rate (BER) performance.

Abstract: A water filter apparatus to filter piped water which is adapted to be coupled to piping of a piped water system, and which includes an elongated tubular housing body in which a solid filter element mounts, in use, extending along the housing, the tubular housing body having a first open end by means of which the filter element may be inserted into or removed from within the tubular housing body, a housing end cap which mounts over the first open end of the housing body and which has an aperture therethrough to, in use, be placed in fluid communication with the interior of a length of piping of the piped water system, and a replaceable filter cartridge including the filter element securely fastened to a supportive end body, to support the filter element within the housing body, the supportive end body having the form of a cap which is fastened over one end of the filter element and which, in use, channels fluid through the filter element to or from the aperture of the housing end cap.

Abstract: The invention relates particularly to the switching of an SDH low order VC-3 using a high order switching apparatus, such as an STS switch. A low order VC-3 is aligned with a TU-3 pointer to form a TU-3. The TU-3 is mapped into a high order VC-3 type data structure which, in turn, is aligned with an AU-3 pointer to form an AU-3 type data structure. The AU-3 type data structure is suitable for switching by the high order switch. After switching, the AU-3 type data structure is combined with similar AU-3 type data structures and converted into an AU-4 suitable for transmission across an SDH/SONET network. Advantageously, the arrangement is such that each AU-3 pointer has the same fixed value. Hence, conversion to an AU-4 is achieved by a fixed pointer replacement operation.

Abstract: A system for providing television, information and data signals via a transmission network to selected subscribers, to groups of subscribers, or to all subscribers connected in common to the transmission network. An address code signal is stored at the subscriber station, and an option code signal is sent to the particular subscriber station from a head end of the network. Signals having an address portion designative of the option code or address code signal are sent down the transmission line and are translated by the subscriber station in the event the address matches the first and second code signal. Thus signals can be sent to all subscribers which have option codes designated by the address of data packets transmitted down the transmission line. These groups of subscribers can be all subscribers, individual smaller groups of subscribers, or a group consisting of even a single subscriber. The option codes can be changed from the head end at will.

Abstract: A method and device for rendering safe the opening or removal of a machine door which is normally kept locked to guard machinery or an area which is potentially hazardous. The device includes a lock unit having a lock body for connection to the frame panel of machinery to be guarded and supports an electrical switch. A key unit includes a key body which supports a rotatable control knob and a key adapted to cooperate with the lock body when the door is closed on the frame panel. The key body includes a radially extending peripheral flange formed with a hole towards its outer edge which rotatably receives the head of a screw. The threaded end of the screw cooperates with a threaded hole in the frame panel when the door is closed and must be screwed fully into the hole to fully close the door onto the panel.

Abstract: An Apparatus for handling flowable material, such as sludge or granular or powder materials, a pneumatically operated annular closure member located in an annular casing is retracted to allow the material to flow into a space at the bottom of the apparatus and is extended to close this space and entrap the material within it. Air pressure is applied to this enclosed space to transport the material from that space through an outlet tube. Opening and closing of the closure member and the application of air under pressure to the material are controlled pneumatically.