Abstract: There is provided an interface module (200), comprising: an interface (208) for connection with a signal connector (250); a cage (206) for guiding the signal connector towards the interface; and a heat sink (202). The cage (206) comprises a cage portion (212) that is configured to move from a first position to a second position upon insertion of the signal connector (250) into the cage. In the first position, the cage portion is not in thermal contact with the heat sink; when in the second position, the cage portion is in thermal contact with the heat sink. The cage portion (212) comprises one or more apertures (218).

Abstract: A sealing unit for a cabinet containing optical components. A gasket defines a plurality of apertures configured to provide a seal around a plurality of optical fiber cables, wherein the gasket has an interior side intended to face the interior of the cabinet and an exterior side intended to face an exterior of the cabinet. A first retaining device is located on the interior side of the gasket, and a second retaining device is located on the exterior side of the gasket. The first and second retaining devices each include a plurality of channels, wherein each channel is aligned with a respective aperture of the gasket and each channel is configured to receive one of the plurality of optical fiber cables. Each channel has a profile defined by a plurality of protruding surfaces configured to restrain longitudinal movement of an optical fiber cable received therein.

Abstract: An electronic circuit board including a plurality of electronic components mounted on the electronic circuit board and a plurality of electricity conductive paths for connecting the electronic components. The electronic circuit board further includes a plurality of electric connectors arranged in a bank along an edge of the electronic circuit board, wherein each one of the plurality of electric connectors is formed from the material of the board as a finger projecting outside the electronic circuit board. In line with either edge of each one of the electric connectors the electronic circuit board has a cut forming a gap and projecting into the board.

Abstract: In A system for mounting an electronic device on a device rack is provided. The device rack is for supporting a plurality of the electronic devices spaced along the rack in a first direction of the system. The system comprises: the electronic device; and a bracket for mounting the electronic device in a device rack, the bracket comprising: a first coupler configured to couple the bracket to the electronic device; a second coupler configured to couple the bracket to the device rack; and a bracket body comprising: a first arm extending between the first coupler and the second coupler; and a second arm extending between the first coupler and the second coupler, wherein the first arm and second arm are spaced apart to define an opening through which one or more cables and/or fibres connected to the electronic device can extend.

Abstract: Embodiments described herein relate to apparatuses for reducing the effect of oscillations of a heat sink. A heat sink apparatus is provided for use with an interface module comprising a cage configured to receive a pluggable signal connector, wherein the cage comprises a first surface configured to couple to a circuit board.

Abstract: There is provided an interface module (200), comprising: an interface (208) for connection with a signal connector (250); a cage (206) for guiding the signal connector towards the interface; and a heat sink (202). The cage (206) comprises a cage portion (212) that is configured to move from a first position to a second position upon insertion of the signal connector (250) into the cage. In the first position, the cage portion is not in thermal contact with the heat sink; when in the second position, the cage portion is in thermal contact with the heat sink. The cage portion (212) comprises one or more apertures (218).

Abstract: An optical add/drop device (100) comprising: a common port (102); an add port (106); a first wavelength selective optical filter (110) configured to: receive an optical signal at an add wavelength from the add port and transmit said optical signal at the add wavelength towards the common port; and receive optical signals from the common port and reflect optical signals not at the add wavelength; a second wavelength selective optical filter (114) configured to receive said optical signals from the common port reflected by the first wavelength selective optical filter and transmit an optical signal at a drop wavelength, different to the add wavelength; a drop port (116); and an optical waveguide (118) configured receive said optical signal at the drop wavelength transmitted by the second wavelength selective optical filter and route said optical signal to the drop port.

Abstract: A sealing unit (210) for cables extending into an enclosure comprising telecommunications equipment. The sealing unit (210) comprising a gasket (101) having an elongate section (110) of resilient material comprising a plurality of apertures (120), wherein each aperture is arranged to receive a cable (300). The elongate section (110) comprises slots (130) connecting the apertures to a lateral edge (150) of the elongate section. The apertures (120) are arranged in a two-dimensional array.

Abstract: An optical add/drop device (100) comprising: a common port (102); an add port (106); a first wavelength selective optical filter (110) configured to: receive an optical signal at an add wavelength from the add port and transmit said optical signal at the add wavelength towards the common port; and receive optical signals from the common port and reflect optical signals not at the add wavelength; a second wavelength selective optical filter (114) configured to receive said optical signals from the common port reflected by the first wavelength selective optical filter and transmit an optical signal at a drop wavelength, different to the add wavelength; a drop port (116); and an optical waveguide (118) configured receive said optical signal at the drop wavelength transmitted by the second wavelength selective optical filter and route said optical signal to the drop port.

Abstract: A cooling system (100) for equipment is disclosed, the equipment comprising an air ingress (104) and an air egress (106). The cooling system comprises a compression chamber (108) arranged to compress air exiting the equipment from the equipment air egress (106), and a refrigerant circuit (110) comprising a condenser coil (112), an evaporator coil (114) and a conduit (116) arranged to convey refrigerant fluid between the condenser coil (112) and the evaporator coil (114). The evaporator coil (114) is arranged to cool air entering the equipment at the equipment air ingress (104) and the condenser coil (112) is located within the compression chamber (108). Also disclosed are methods (300, 400) and apparatus for cooling equipment.

Abstract: There is provided an interface module, having an interface for connection with a signal connector, a cage for guiding the signal connector towards the interface and a heat sink. The cage includes a cage portion that is configured to move from a first position to a second position upon insertion of the signal connector into the cage. In the first position, the cage portion is not in thermal contact with the heat sink. When in the second position, the cage portion is in thermal contact with the heat sink.

Abstract: There is provided an interface module, including an interface for connection with a signal connector, a cage for guiding the signal connector towards the interface and a heat sink. The cage has a cage portion that is configured to move from a first position to a second position upon insertion of the signal connector into the cage. In the first position, the cage portion is not in thermal contact with the heat sink. When in the second position, the cage portion is in thermal contact with the heat sink.

Abstract: A cooling system (100) for equipment is disclosed, the equipment comprising an air ingress (104) and an air egress (106). The cooling system comprises a compression chamber (108) arranged to compress air exiting the equipment from the equipment air egress (106), and a refrigerant circuit (110) comprising a condenser coil (112), an evaporator coil (114) and a conduit (116) arranged to convey refrigerant fluid between the condenser coil (112) and the evaporator coil (114). The evaporator coil (114) is arranged to cool air entering the equipment at the equipment air ingress (104) and the condenser coil (112) is located within the compression chamber (108). Also disclosed are methods (300, 400) and apparatus for cooling equipment.

Abstract: An in band control channel is created between nodes of a communication network in which the nodes have limited capability of inspecting the payload of packets to be transported over the network. The in band control channel is created by transmitting a plurality of dummy packets, each dummy packet having one of a plurality of different predetermined lengths, the sequence of dummy packets defining a code corresponding to at least one control command.

Abstract: A boundary node for interworking between a first network and a second network comprises first equipment for interfacing with the first network and second equipment for interfacing with the second network. The first equipment comprises a switch fabric. A first interworking interface and a second interworking interface are provided for carrying traffic between the second equipment and the first equipment. Each of the interworking interfaces is for interfacing with a respective traffic-carrying path of the second network. For traffic flow in a direction from the second network to the first network, a method comprises determining that recovery switching is required for traffic on one of the traffic-carrying paths of the second network and performs a recovery switch, using the switch fabric in the first equipment, to switch between the interworking interfaces to achieve a recovery switch between the traffic-carrying paths of the second network.

Abstract: A method distributes clock synchronization information within an optical communications network that includes a plurality of network elements. The method receives an ingress clock synchronization message at a first network element. The ingress clock synchronization message includes a clock synchronization message identifier and a correction field. The clock synchronization message identifier is inserted into an optical channel frame overhead and the ingress clock synchronization message is inserted into an optical channel frame payload. The optical channel frame overhead and the optical channel frame payload are transmitted across the first network element, across the network to a second network element, and across the second network element. A transit time of the clock synchronization message identifier is determined across each of the network elements.

Abstract: The invention relates to data networks, and in particular relates to a method and apparatus for forming and processing data units to enable the transfer of clock quality information in data networks. A method of forming a higher order data unit, comprising payload data and overhead data, from a plurality of lower order data units, is disclosed. The payload of the higher order data unit is formed by combining the plurality of lower order data units. The overhead data of the higher order data unit includes clock quality information relating to clocks associated with the plurality of lower order data units. Embodiments provide a way of transporting clock quality information relating to clocks associated with a number of lower order data units within a single higher order data unit, and enables intermediate networks easily to access the clock quality information.

Abstract: For protecting traffic on paths extending from a source client entity (CE1) to a destination client entity (CE2) via an optical transport network and attachment circuits at ingress (A,B) and egress (C,D) nodes, there are multiple paths within the OTN network, and the attachment circuits are dual homed. By sending (120) an indication of operational status of the dual homed attachment circuits within overhead associated with the traffic and sent with the traffic through the network, a selection can be made (130) of which of the provided paths and attachment circuits to use for the traffic, based on the indicated operational status, and on OTN fault detection, to protect against a fault in the attachment circuit or in the OTN network. Thus protection can extend across the edge nodes without the complexity and delays involved in interworking of separate protection schemes and without a control plane.

Abstract: For protecting traffic from a source client entity (CE1) to a destination client entity (CE2) via an optical transport network and attachment circuits at ingress (A,B) and egress (C,D) nodes, there are multiple paths within the OTN, and the attachment circuits are dual homed. By sending (120) an indication of operational status of the dual homed attachment circuits within overhead associated with the traffic and sent with the traffic through the network, a selection can be made (130) of which of the provided paths and attachment circuits to use for the traffic, based on the indicated operational status, and on OTN fault detection, to protect against a fault. Thus protection can extend across the edge nodes without interworking of separate protection schemes and without a control plane. Traffic flows can be multiplexed at the ingress, with the indication in the overhead having separate indications for each of the traffic flows.

Abstract: A method distributes clock synchronization information within an optical communications network having a plurality of network elements. The method receives an ingress clock synchronization message at a first network element. The ingress clock synchronization message includes a clock synchronization message identifier and a correction field. The clock synchronization message identifier is inserted into an optical channel frame overhead and the ingress clock synchronization message is inserted into an optical channel frame payload. The optical channel frame overhead and the optical channel frame payload are transmitted across the first network element, across the network to a second network element, and across the second network element. A transit time of the clock synchronization message identifier is determined across each of the network elements.