Abstract: An apparatus and method reduce jitter in SPE data transmitted to a switch fabric. A processor receives STS channel requests from the switch fabric, and retrieves SPE data in buffers assigned to the requested STS channels. The processor loads the SPE data in the PDU of a TDM cell, the TDM cell in the PDU of a PIC, and a length of the SPE data in the header of the PIC. The PIC is then embedded in a CSIX frame that is transmitted to the switch fabric through a CSIX interface. The length of the SPE data in the PIC PDU is variable since the processor retrieves SPE data upon demand from the switch fabric. Thus, even if enough data to fill an entire PDU is not in a channel buffer at the time of a channel request, the available data is transmitted so that the opportunity to transmit available SPE data is not lost.

Abstract: A synchronization state for a local clock generating circuit of a first of a number of components of a distributed system is maintained according to a number of local clock cycles recorded between successive occurrences of a global synchronization signal provided to the components within the distributed system. The local clock generating circuit may enters the synchronization state only after observing a predetermined number of occurrences of successive local clock cycles between instances of the global synchronization signal. The local clock generating circuit continues to provide local control signals for the first of the components at time instants corresponding to the number of local clock cycles even after an instance of the global synchronization signal is observed at a time instant corresponding to one local clock cycle more or less than the number of local clock cycles.

Abstract: A method of managing a network switch. The method having the first step of detecting a status of a set of physical ports on an interface card in the network switch. Then, determining if the status is in a first state that indicates that all physical ports in the interface card are inaccessible. If the status is in the first state, then accepting all traffic for the set of physical ports. Also disclosed is an apparatus for performing the method.

Abstract: An apparatus and method for reducing congestion in a network switching node. A congestion mask that indicates which of a plurality of destination ports in a network switching node are congested is generated and combined with a destination port field included in a packet in a multicast queue of the switching node to mask destination port designations in the destination port field that are indicated by the congestion mask to be congested if a drop eligibility field within the packet indicates that destination port designations are permitted to be masked. The packet is dequeued from the multicast queue to be forwarded to destination ports in the network switching node indicated by destination port designations in the destination port field not masked by the combination of the congestion mask with the destination port field.