摘要:
A test system for performing pair gain tests within a co-axial cable termination unit of a combined telephony/video system is described. The combined telephony/video system provides a set of telephony channels and video channels to the co-axial cable termination unit over a single combined telephony/video transmission line. The co-axial cable termination unit includes interface circuitry in the form of modems, CODEC's, and the like, for interfacing the set of telephony channels provided on the combined telephony/video transmission line with a set of respective telephone lines connected into a subscriber location The interface circuitry also routes the video channel of the combined telephony/video transmission line onto a video-only co-axial cable also connected into the subscriber location. To accommodate pair gain testing, the co-axial cable termination unit also includes a pair gain test unit for verifying the operation of a single telephony channel provided on the combined telephony/video transmission line and a switch for connecting the pair gain test unit to a selected one of the set of telephone lines connected to the interface system to permit the test unit to test the telephony channel associated with the selected telephone line. In this manner only a single pair gain test unit is required within each co-axial cable termination unit.
摘要:
An automatic switching system and method is provided for switching between paths in a telecommunications switching system. A first circuit in each path receives substantially identical telecommunications signals containing telecommunications data and transmits substantially identical digital signals containing the telecommunications data. The first circuit is capable of detecting whether errors have occurred during transmission of the telecommunications signals, and of inserting into the digital signals an error indicator if a transmission error has been detected. At least one second circuit in each path accepts the digital signals from the first circuit in a selected path, and is capable of detecting whether the error indicator is present, and automatically switching to accept the digital signals from the first circuit in the non-selected path in response to detection of the error indicator.
摘要:
A housing (10) for a cooling fan (56) includes a first side wall (12) and a second side wall (14) separated by a front wall (16). A first wall portion (22) extends from the first side wall (22) toward the second side wall (14) and opposite from the front wall (16). A second wall portion (26) extends from the second side wall (14) toward the first side wall (12) and opposite from the front wall (16). A first flexible member (30) on the first wall portion (22) extends along the first side wall (12) and is arched toward the front wall (16). A second flexible member (32) on the second wall portion (26) extends along the second side wall (14) and is arched toward the front wall (16). A cooling fan (56) is inserted into the housing (10), compressing the first flexible member (30) and the second flexible member (32) that force the cooling fan (56) against the front wall (16). The front wall (16) may include tabs (42, 46, 48, 50) to enhance the ability to secure the cooling fan (56) within the housing (10).
摘要:
The invention comprises a time slot interchanger and method for multiplexing ISDN D-channel signals into multiplexed signals in a digital communications terminal. One method comprises receiving a frame of communication signals wherein some of the communication signals represent ISDN D-channel signals wherein each ISDN D-channel signal is represented by a first number of data bits and a second number of other bits. The first number of data bits are stored in one of four memories--a first memory, second memory, third memory or fourth memory. The data bits are stored during a first frame period. Multiplexed signals are then assembled wherein a multiplexed signal comprises a multiplexed combination of the data bits of ISDN D-channel signals retrieved from the frame of communications signals. The multiplexed signals are assembled by storing the data bits of at least two ISDN D-channel signals, each set of data bits stored at the same memory address but in a separate one of the first, second, third or fourth memories.
摘要:
The invention comprises a time slot interchanger and method for multiplexing ISDN D-channel signals into multiplexed signals in a digital communications terminal. The method comprises receiving a frame of communication signals wherein some of the communication signals represent ISDN D-channel signals. The frame of communication signals is stored in memory during a first frame period. During a second frame period, at least some of the stored communication signals are retrieved from memory. Multiplexed signals are assembled wherein each multiplexed signal comprises a multiplexed combination of the data bits of ISDN D-channel signals retrieved from memory. The multiplexed signals are then output during a second frame period.
摘要:
A timing system (100) for coordinating the components of a distributed digital cross-connect system (10) is provided. The timing system (100) includes a master timing system (102) that receives a network timing reference (98, 99) and generates a master timing signal. A distributed services node timing system (104, 106) is connected to the master timing system (102) and receives the master timing signal. The distributed services node timing system (104, 106) then embeds a timing signal in a data transmission frame (150). Two or more digital cross-connect timing systems (108) are connected to the distributed services node timing system (104, 106) and receive the data transmission frame (150). The digital cross-connect timing systems (108) retrieve the embedded timing signal from the data transmission frame (150).
摘要:
A method (100) for preventing message looping in a telecommunications network (70) includes the steps of receiving a UDT/S query message, determining a next destination for processing the query message and a route for delivering the query message to the next destination (102). A determination is then made as to whether the route to the next destination is XUDT/S capable (104). The UDT/S query message is converted to an XUDT/S format by inserting a hop counter (38) therein if the route is XUDT/S capable (108). The query message is then delivered to the next destination via the route (110). The hop counter (38) in the query message is then decremented at the next destination in response to receiving a message of the XUDT/S format (112). A message loop error is recognized and processed when the hop counter (38) reaches a predetermined value.
摘要:
A technique for providing access to a switch fabric is disclosed. In some embodiments, the method comprises determining scheduling information specific to a link to the switch fabric and using the scheduling information to determine a queue to be serviced by the link. In some embodiments, the system comprises a buffer configured to store a plurality of queues, and a queue scheduler associated with the buffer and configured to determine scheduling information specific to a link to the switch fabric and use the scheduling information to select one of the plurality of queues as the next queue to be serviced by the link.
摘要:
An apparatus and method for analyzing data streams in a data transmission environment. In one embodiment, the method involves: capturing data from at least one data stream at two or more taps associated with a system under test (SUT); filtering the captured data to extract data packets belonging to one or more data types; analyzing extracted data packets of each data type using packet header and payload information of the extracted data packets; and outputting results obtained from analyzing the extracted data packets.
摘要:
An actuating device for a connector having a push-pull coupling mechanism is disclosed. The device comprises a release pull integrated with the connector and configured to operably engage the push-pull coupling mechanism, and a grip, coupled to the release pull and remote from the push-pull coupling mechanism, to which force may be applied to cause the release pull to actuate the push-pull coupling mechanism.