61 results about "Alarm indication signal" patented technology

In an OTN (Optical Transport Network), an OTN interface of a network element may receive a BDI (Backwards Defect Indicator) signal from a far end network element to which OTN frames are being transmitted. A BDI signal indicates the occurrence of a unidirectional failure in the transmission of OTN frames to which the far end network element responds by switching its routing to the network element. The OTN interface generates an AIS (Alarm Indication Signal) for its network element so that the network element switches network communication channels to the far end network element to ensure bidirectional switching upon a unidirectional failure.

A method of detecting signal degrade in an ATM network, and a network element using such method are disclosed. Signal degrade at the ATM layer of the network is detected by monitoring signal degrade at the physical layer of the network. In response, ATM cells indicative of the signal degrade may be generated at the ATM layer, and protection switching may be effected. Preferably, signal degrade at the physical layer may be monitored by determining a bit-error-rate at the physical layer. ATM alarm indication signal (“AIS”) cells or ATM protection switching coordination protocol (“CP”) cells may be generated to effect the protection switching.

An embodiment of the invention discloses a controlling method for a WiFi protected setup and equipment thereof, which are used for ensuring high safety in accessing the WPS. The controlling method for the WiFi protected setup according to an embodiment of the invention comprises the steps of: acquiring a WPS accessing request of first user equipment, wherein the WPS accessing request carries a personal identification number PIN; according to the WPS accessing request, outputting an alarm indication signal to second user equipment so that the second user equipment transmits a first instruction or a second instruction according to the alarm indication signal; if the first instruction which is transmitted by the second user equipment is acquired, receiving the WPS accessing request and stopping the alarm indication signal; and if the second instruction which is transmitted by the second user equipment is acquired, refusing the WPS accessing request and stopping the alarm indication signal.

The invention provides a three-phase alternating voltage phase sequence monitoring system, including: a step-down filtering and shaping circuit; a comparator circuit which compares a three-phase alternating voltage processed by the step-down filtering and shaping circuit with a reference voltage and outputs a three-channel comparison result; a logic circuit which detects a phase sequence of the three-phase alternating voltage according to the three-channel comparison result and outputs a judgment signal; a driving protection circuit which drives a relay according to the judgment signal; and a relay which generates an indication signal according to an output signal of the driving protection circuit, outputs a phase sequence correct indication signal when the phase sequence of the three-phase alternating voltage is correct, and outputs an alarm indication signal when the phase sequence of the three-phase alternating voltage is in disorder or a phase loss occurs. The three-phase alternating voltage phase sequence monitoring system provided by the invention detects the phase sequence of the three-phase alternating voltage, thereby driving the relay, and protecting safety of electric equipment, and effectively avoiding unnecessary loss brought by the problems of phase sequence disorder and phase loss; and at the same time, since the three-phase alternating voltage phase sequence monitoring system is integrated in a circuit module of a chip, the system is small in size, and the system is convenient to operate and high in detection precision.

The invention provides a thermocouple welding detection device which comprises a signal selection circuit, a first comparison circuit, a second comparison circuit, a switching circuit and an alarm indication circuit. The signal selection circuit is electrically connected with a thermocouple. The signal selection circuit receives a selection signal and outputs a first direct current voltage to the first comparison circuit or outputs a second direct current voltage to the second comparison circuit according to the selection signal. The first comparison circuit compares the first direct current voltage with a first reference voltage and then outputs a first control signal. The second comparison circuit compares the second direct current voltage with a second reference voltage and then outputs a second control signal. The switching circuit receives the first control signal and the second control signal and outputs an alarm indication signal according to the first control signal and the second control signal. The alarm indication circuit receives the alarm indication signal and indicates the welding conditions of thermocouple wires of the thermocouple according to the alarm indication signal.

The invention relates to a channel protection method of a looped network system with IP RAN (Internet Protocol-Radio Access Network) forward compatible with MSTP (Multi-Service Transport Platform). If a fault occurs in an IP RAN network, the bidirectional forwarding detection conversation of an IP RAN equipment host node stays in a failure state, IP RAN equipment compatible with MSTP businesses converts the failure state of the PW (Pseudo-Wire) layer bidirectional forwarding detection conversation into a channel alarm indication signal of MSTP at a butting position, and MSTP equipment carries out concurrent transmitting and selective receiving protection switch on channels. If the fault occurs in an MSTP network, the MSTP equipment at both ends of a fault point respectively insert the channel alarm indication signal to the downstream till the butting position between the MSTP network and the IP RAN network; and at the butting position, the IP RAN equipment compatible with the MSTP businesses stops sending pseudo-wire bidirectional forwarding detection conversation frames, and the IP RAN equipment host node carries out the concurrent transmitting and selective receiving protection switch on the channels. The invention realizes the channel protection of the looped network system with IP RAN forward compatible with MSTP.

A bidirectional line switched ring network which enables high-speed operation with improved reliability because of a reduced software processing load is disclosed, and the network includes a plurality of optical transmission equipment sets connected in a ring form, wherein optical transmission equipment provided in a node on the transmission side performs transmission to each lower-order channel by attaching a transmission-side node ID, and, optical transmission equipment provided in a node on the reception side collates the received transmission-side node ID with an expected value of the transmission-side node ID having been set in advance, and when the collation does not match, the optical transmission equipment in the node on the reception side prevents a misconnection in the event of a failure by inserting an alarm indication signal.

The invention provides a method and device for transmitting messages. An aggregated link trunk is set between a first device and a second device. A state machine of a maintenance association end point(MEP) of the first device is currently located on a first single board of the first device. The level of the MEP of the first device is different from that of the MEP of the second device. The methodcomprises the steps that when the state machine of the MEP of the first device is migrated from the first single board to a second single board of the first device, the first device suppresses faultalarm and sends an alarm indication signal (AIS) to the second device according to a preset frequency; and when the state machine of the MEP of the first device is migrated completely from the first single board to the second single board of the first device, the first device recovers the fault alarm and stops sending the AIS. The false alarm resulting from state machine migration timeout is effectively suppressed through utilization of the alarm indication signal (AIS). The method and the device are simple and feasible. Interconnection is not influenced.

The invention discloses a method for preventing the defect transparent transmission of a section layer of synchronous digital hierarchy equipment, which relates to the technical field of synchronous digital transmission. The method comprises the following steps of: detecting a main service data frame of a service data interface, jointed with a crossing unit, on the optical interface unit system side of the synchronous digital hierarchy (SDH) equipment in real time, and judging the main service data frame gives an out of frame (OOF) alarm or not; when the main service data frame is judged to give the OOF alarm, inserting an administrative unit-alarm indication signal (AU-AIS) in the direction of the optical interface unit line side of the SDH equipment; and when the AU-AIS passes through the optical interface unit line side of the SDH equipment, performing scrambler processing and downwards transmitting the processed AU-AIS. By the method, clock abnormities can be prevented from causing the defects of error codes, alarm and the like of the section layer comprising a regenerator section and/or a multiplexing section at each downstream site, so the security of services of sites non-adjacent to a failing site is greatly improved.