Abstract: A method of and apparatus for allocating memory for storage of vocabularies used in adaptive data compression of a frame-multiplexed data stream of a data communications network. More specifically, a memory of a data compression encoder of the network is partitioned into a plurality of sections for the temporary storage of a corresponding plurality of data compression vocabularies. A memory section of the plurality is assigned to a current frame of the frame-multiplexed data stream based on information of the current frame for storage of a vocabulary created adaptively from the current frame.

Abstract: A queueing and dequeueing mechanism for use in an integrated fast packet network, wherein fast packets from differing traffic types are multiplexed with one another through use of a weighted round-robin bandwidth allocation mechanism (517). Fast packets within a particular traffic type are selected for transmission through use of a head of line priority service (514), a packet discard mechanism (516), or both. The weighted round-robin bandwidth allocation mechanism functions, in part, based upon a credit counter for each queue group that represents a particular traffic type.

Abstract: Information encoded by data compression (or another data encoding technique, e.g., encryption, requiring synchronization between the encoder and decoder) is transmitted over an unreliable network by checking for transmission errors after decoding. If an error is detected, the encoder is reset, using a reset protocol which may operate over an unreliable reverse channel by using a timer to generate further reset requests when the receiver does not acknowledge them in a timely fashion.

Abstract: This invention is suited for a packet network that carries bursty data. A mechanism is coupled to an edge node for coding bursty information into a digital format at either a first coding rate of a second coding rate which is less than the first rate. A mechanism senses traffic overload of one or more intermediate nodes carrying the bursty informaton. A mechanism which is responsive to the overload sensing mechanism causes the coding mechanism to switch from the first rate to the second rate while a traffic overload is sensed. Thus, network demand requirements are reduced and the overload will be alleviated.

Abstract: The present invention relates to a multichannel multihop lightwave communication network which allows packet concurrency in the network while avoiding the need for agile optical devices. The network comprises a lightwave communication medium (10) for supporting a plurality of independent user nodes; and a plurality of N network interface units (NIUs) (11). Each NIU is connected to the lightwave medium and one or more separate user nodes and comprises a trnasmitter section (28-35) and a receiver section (20-27) which are each fixedly assigned to transmit and receive, respectively, over a single channel or a plurality of separate channels to or from other NIUs of the network. In a connectivity pattern for one embodiment of the network, the NIUs are divided into k groups of p.sup.k NIUs such that each NIU of a first group of p.sup.

Abstract: The present invention relates to an N-input, N-output "Knockout" packet switch (11) which uses decentralized control and distributed routing. More particularly, within the switch, the N input signals comprising fixed-length packets propagate along separate broadcast buses (14) to each of N bus interface units (15) which include N packet filters (20), a concentrator (21) and a shared buffer (22). Each bus interface unit is associated with a separate one of the N outputs (12) of the switch, and the N packet filters therein are each associated with a separate one of the N broadcast buses for detecting if a packet on the associated bus is destined for the associated switch output. The concentrator is used to reduce the number of separate buffers needed to receive packets which may arrive simultaneously and are destined for the associated output. Contending packets at the output of the concentrator are stored in the shared buffer before placement on the output line on a first-in, first-out basis.

Abstract: The present invention relates to an N-input, N-output "Knockout" packet switch (11) which uses decentralized control and distributed routing for routing high-speed, time-multiplexed, variable-length packets of information from the N inputs to the N outputs. More particularly, within the switch, the N input signals are separately synchronized such that the start of each arbitrarily arriving variable-length packet is synchronized to the start of a next mini time period of a sequence of mini time periods common to all inputs. The synchronized N input signals then propagate along separate broadcast buses (14) to each of N bus interface units (15) which include N packet filters (20), a concentrator (21) and a shared buffer (22) capable of processing variable-length packets.

Abstract: A trunk circuit interfaces a multichannel data signal to a communication facility using a high priority queue (HPQ) memory, a low priority queue (LPQ) memory, and a data packet sorter including a separate LPQ counter for each data channel. Each LPQ channel counter keeps track of data packets from the associated channel which are stored in the LPQ memory. The packet sorter sorts data packets according to size. Small data packets from each channel which are smaller than a predetermined length are sorted for storage in the HPQ memory only when the associated LPQ channel counter is zero. Small data packets having a non-zero LPQ channel count and large data packets are stored in the LPQ memory. The trunk circuit first transmits data packets from the HPQ memory and then from the LPQ memory.