Abstract: In a passive optical network, dynamic bandwidth allocation and queue management methods and algorithms, designed to avoid fragmentation loss, guarantee that a length of a grant issued by an OLT will match precisely the count of bytes to be transmitted by an ONU. The methods include determining an ONU uplink transmission egress order based on a three-stage test, and various embodiments of methods for ONU report threshold setting.

Abstract: A method or system or apparatus provides improved data handling. In one aspect, destination scheduling is performed by scheduling polling rather than scheduling data emissions. In particular aspects, a scheduler assigns a weight and sequence number to each destination and tracks a port segment count and schedules polling of ports using these parameters.

Abstract: Methods and apparatuses for controlling transmission of converged data packets and for media access through a single next generation access (NGA) passive optical network (PON) which can coexist with EPON and GPON based systems and can interoperate with a 10 GEPON. A converged data packet is transmitted between a first node and a second node of the NGA network under NGA management control. The converged packet has a format which unifies a GEM header with the 10 GEPON preamble header and certain fields replaced in a EPON packet format to accommodate information corresponding to the preamble elements of a GEM packet. The converged data can be encoded in the line code of the 10 GEPON protocol, allowing use of a control protocol based either on MPCP or GTC for the NGA. Node apparatuses include NGA elements which enable preparation, encoding/decoding and transmission of converged packets.

Abstract: The present invention discloses methods for reducing power consumption in a PON while maintaining service continuity, the method including the steps of: providing an OLT operationally connected to at least one ONU; triggering a sleep request for at least one requesting ONU; upon receiving a sleep acknowledgement, activating a sleep mode for at least one requesting ONU according to a sleep period designated in the sleep request; and terminating the sleep mode according to the sleep period. Preferably, the sleep acknowledgement is transmitted from the OLT to the requesting ONU. Preferably, the sleep period is executed by a sleep command in the sleep acknowledgement. Preferably, the method further includes the step of: upon completion of the sleep period, transmitting buffered data traffic from the OLT to a sleeping ONU. Preferably, the step of transmitting is performed without the sleeping ONU being re-registered and without causing packet reordering.

Abstract: Methods and apparatus for finding a match between a target bit pattern and multiple filter bit patterns. A filter array is created from the filter bit patterns and at least one intermediate array is generated from the filter array. Specific columns of the intermediate arrays are then extracted based on bit values of the target bit pattern. A row by row AND operation is performed on these columns to arrive at a match vector. the match vector identifies which of the filter bit patterns in the filter array match the target bit pattern. The method is implemented by using multiple classifier elements operating in parallel with each classifier element handling multiple filter bit patterns.

Abstract: Methods and devices for controlling and managing data flow and data transmission rates. A feedback mechanism is used in conjunction with measuring output transmission rates to control the input transmission rates, changing conditions can be accounted for an excess output transmission capacity can be shared among numerous input ports. Similarly, by using maximum and minimum rates which can be requested from an output port, minimum transmission rates can be guaranteed for high priority traffic while capping maximum output rates for low priority traffic. By combining the two ideas of feedback rate control and placing maximum requestable transmission rates, a more equitable output sharing mechanism arises. The measured output transmission rate is used to control and recalculate the maximum requestable output transmission rate for incoming flows, thereby allowing for changing network and data flow conditions.

Abstract: A phase detector customized for Clock Synthesis Unit (CSU) is disclosed. The phase detector improves jitter performance by providing minimal activity on VCO control lines and pushing ripple frequency to one octave higher, while maintaining wide linear characteristic. Moreover, it provides a frequency-scalable circuit that unlike a conventional phase-and-frequency detector (PFD), does not rely on asynchronous elements.

Abstract: Methods and devices for controlling and managing data flow and data transmission rates. A feedback mechanism is used in conjunction with measuring output transmission rates to control the input transmission rates, changing conditions can be accounted for an excess output transmission capacity can be shared among numerous input ports. Similarly, by using maximum and minimum rates which can be requested from an output port, minimum transmission rates can be guaranteed for high priority traffic while capping maximum output rates for low priority traffic. By combining the two ideas of feedback rate control and placing maximum requestable transmission rates, a more equitable output sharing mechanism arises. The measured output transmission rate is used to control and recalculate the maximum requestable output transmission rate for incoming flows, thereby allowing for changing network and data flow conditions.

Abstract: Methods and apparatus for reducing the search space processed by mask matching methods. The search space is reduced by grouping the candidate bit patterns into groups and subgroups that have internal bit agreement between the members. By only applying the mask matching methods to a select number of groups selected by their bit agreement with the target bit pattern, the computation time and memory requirement of the mask matching method is reduced.

Abstract: Methods, systems, and apparatus for processing packet fragments for reassembly into packets. Datastreams containing packet fragments are received and data corresponding to different channels are segregated. For each channel, data is then aggregated to recreate packet fragments. Once the fragments are recreated, they are, if required, resequenced using a two-tier memory mapping structure where only pointers, and not the fragments, are manipulated. After resequencing fragments to reassemble the packet, the reassembled packet is dispatched to its ultimate destination. The present invention also provides a method of load balancing between multiple links when packet fragments are transmitted from a fragmenting node through a multiple link bundle.

Abstract: Methods and devices for scheduling data transmission processing based on the size of the data transmission unit and a predetermined increment value. A scheduler has slots which represent specific amounts of time in which a queue of data transmission units to be processed is represented. An indicator determines which slot and thereby which queue is being examined. Each queue is assigned a specific increment value and each data transmission unit in a queue is assigned a count value based on the size of the data transmission unit. When a data transmission unit is at the head of the queue and is a candidate for processing, if the count value is greater than a predetermined value then the queue and thereby the data transmission unit at the head of the queue is rescheduled at a later time. This is effected by assigning the queue to a subsequent slot in the scheduler. The subsequent slot in the scheduler is determined based on the given increment value for that queue.

Abstract: This invention provides a bus interface to connect SONET/SDH termination devices with payload processing devices while utilizing a minimum number of signals. The bus interface of this invention can scale with future advances in bandwidth in serial link technology.

Abstract: Over-sampled timing signal jitter tolerance is improved in a q-times over-sampled architecture by phase-sampling the timing signal to produce a plurality of input phase samples &phgr;in, where &phgr;in&egr;{&phgr;1, &phgr;2, . . . , &phgr;q}. An output phase value &phgr;out=&phgr;in is initialized for each input sample &phgr;in. A difference vector di is derived for each input sample &phgr;in, where di=Fj(n,k). F denotes a vector operation, n is the number of input samples, k is a pre-defined threshold value, and j represents a filter order value. A predefined scaling coefficient ai is applied to each difference vector di to produce a corresponding set of scaled difference vectors ai di. The scaled difference vectors are summed: d j = ∑ i = 1 n ⁢ a i ⁢ d i .

Abstract: The present invention comprises a method of Gray encoding/decoding of binary and Gray code sequences that are less than full-length, resulting in a geometrically reduced storage requirement.

Abstract: A method of reducing error-multiplication due to error events in a cell stream transmitted as a plurality of cell sub-streams which includes the steps of receiving an incoming cell stream in the form of an ordered sequence of cells including payload cells, transmitting the incoming cell stream in a round robin fashion on a plurality of physical links such that the ordered sequence of cells is transmitted as a plurality of cell sub-streams, with each cell sub-stream having a multiplexed set of cells from the incoming cell stream, and inserting stuff (st) cells into the cell sub-streams so as to form continuous streams of data. Sequence number cells which are inserted periodically into each cell sub-stream, are used to align the cell sub-streams in frames. Sets of cell location information for the cell sub-streams are encoded and contain the location of payload cells and st cells located within a corresponding cell sub-stream.

Abstract: A data traffic management system that has the capability of writing data to the buffer memory at twice its normal rate. The data traffic management system uses a pointer structure that can reference either a single or a dual segment memory bank. A dual segment memory bank enhances the write capability of the data traffic management system by allowing two segments to be simultaneously written to both segment memory banks, with one segment being written to each bank. A pointer data structure with a single/dual indicator (S/D indicator) is used for referencing the memory banks. If the S/D indicator has a D entry, then a dual segment memory bank is addressed. The S/D indicator will have an S entry if a single segment memory bank is addressed. Based on the contents of the S/D indicator, either a single fixed size data segment is written to a single memory bank or two fixed size data segments are written to a dual segment memory bank.

Abstract: Methods and devices for arranging memory access operations to minimize memory bank conflicts between such operations. A fixed pattern of memory access operations is implemented to minimize the effects of a transition between a read memory access operation and a write memory access operation. A write-read-gap (WRG) set pattern of a write memory access operation followed by a read memory access operation and then followed by a set gap when no memory access operation may be undertaken, meets the particular requirements of RDRAM. Within the WRG pattern, read addresses and write addresses are selected to minimize memory bank access conflicts. Such selections are assisted in increasing the efficiency of the memory access operations by defining a set frame size of a specific number of repetitions of the WRG pattern. All memory access operations are then rearranged to conform to the WRG pattern and, the repetitions of the WRG pattern are divided into frames having a size equal to that of the defined frame size.

Abstract: A method and apparatus for switching n data streams for input and output of the data streams by an n input, n output data store without data loss. The data store is divided into n separate storage arrays and each data stream is divided into n equal-sized pieces. Then, during each one of n separate time units, one data stream piece is written into a corresponding one of the storage arrays; or, one data stream piece is read from a corresponding one of the storage arrays. For each data stream, during each time unit i, where 1≦i≦n an ith data stream piece is written into an ith one of the storage arrays, or an ith piece is read from an ith storage array. During each jth time unit, where 1≦j≦n, one data stream piece Pij is written into an ith storage array, or one piece Pij is read from an ith storage array.

Abstract: A method of communicating data frames between nodes in a network comprised of one or more end system nodes where each end system node has a unidirectional ingress port and a unidirectional egress port. The method comprises transmitting a data frame from an egress port of one end system node to the ingress port of another end system node, the receiving end system node then determining whether it is the final destination for the data frame. If the receiving end system node is the final destination of the data frame, the receiving end system node absorbs the message. If not, the receiving end system node buffers and then retransmits the data frame through its own egress port. The method provides scalability, low cost, distributed pipeline scheduling, maximum complexity of the network fabric, and maximum speed.

Abstract: A ring interface is coupled to a current node in a ring network having a plurality of nodes and corresponding ring interface for each of said nodes. The ring interface includes a ring input port operative to conduct upstream message packets from a previous node to the ring interface, a ring output port operative to conduct message packets to a next node of the ring network, and a bypass queue operative to buffer message packets. A receive queue buffers message packets before passing them on to the current node. An address filter is coupled to the ring input port to receive the upstream message packets, read their destination addresses and pass them to the bypass queue if the addresses correspond to another node and pass them to the receive queue if their addresses are that of the current node.