A data network (100) provides independent transmission channels (140, 130) for transmitting high bandwidth and low latency information data packets between nodes (150, 160, 180, 190). The data information packets are organized into at least two groups of data packets according to predetermined criteria. The predetermined criteria includes a latency budget of the data packets, the size of the data packets and the type of operation. The low latency channel (130) is also coupled to transmit control information relating to network protocol.

Data network with independent transmission channels

In a system with multiple requesters making multiple requests for resources, an arbiter prioritizes requests based on the number of requests made by a requester. The highest priority is given to a requester that has made the fewest number of requests. Priority may instead be based on the number of requests made for a particular resource. Priority may also be based on a combination of number of requests made by a requester and number of requests made for a resource. The arbiter may also implement a starvation avoidance mechanism such as a round robin scheme.

Least choice first arbiter

Available time slot(s) in a packet switch are identified in order to route a packet from an input port to a designated output port The status of each time slot is logically combined with regard to the input port and with regard to the output port to generate the status of the time slot with regard to the given input port-output port pair The status of input port-output port pairs is logically combined in pairs to determine whether one of the input port-output port pairs is available and the step of pair-wise logically combining the status of input port-output port pairs is repeated to determine input port-output port pair availability until one available input port-output port has been identified

Method and apparatus for parallel packet switching

An arbiter is used so multiple users can use shared resources. The arbiter allocates at least one of the resources speculatively to one of the users for use during a particular access interval in the absence of a request for the resource from the user. The arbiter can also allocate one or more of the resources for use during the particular access interval in response to requests received by the arbiter for the resource(s). That is, a particular access interval may include both speculative and non-speculative allocation of resources by the arbiter.

Method and apparatus for speculative arbitration

A system includes a plurality of resources and a plurality of requesters. A first portion of the resources are reserved for a particular time period in the system during a first arbitration phase, in response to prescheduling requests. During a second arbitration phase a second portion of the resources are allocated in response to regular requests, the first portion of the resources which are reserved being unavailable to the regular requests.

Prescheduling arbitrated resources

A method for path allocation for use with three-stage ATM switches that feature multiple channels between the switch modules in adjacent stages is described. The method is suited to hardware implementation using parallelism to achieve a very short execution time. This allows path allocation to be performed anew in each time slot. A detailed description of the necessary hardware is presented. This hardware counts the number of cells requesting each output module, allocates a path through the intermediate stage of the switch to each cell, and generates a routing tag for each cell, indicating the path assigned to it. >

/pdf/path-allocation-in-a-three-stage-broadband-switch-with-2yx8p8xc80.pdf

Path allocation in a three-stage broadband switch with intermediate channel grouping

A criterion for a three-stage network to be strictly non-blocking is presented which is very general in its application. The criterion distinguishes between channel grouping and link speedup as methods of increasing the bandwidth available to calls. It may be applied to both circuit-switched and packet-switched networks. The non-blocking conditions for various networks are shown to be special cases of the condition presented here.

/pdf/the-strictly-non-blocking-condition-for-three-stage-networks-5gplo5hrt0.pdf

The strictly non-blocking condition for three-stage networks

A method of cell-level path allocation for three-stage ATM switches has previously been proposed by the authors. The performance of ATM switches using this path allocation algorithm has been evaluated by simulation, and is described. Both uniform and non-uniform models of output loading are considered. The algorithm requires knowledge of the number of cells requesting each output module from a given input module. A fast method for counting the number of requests is described. >

/pdf/cell-level-path-allocation-in-a-three-stage-atm-switch-5422a00epa.pdf

Cell-level path allocation in a three-stage ATM switch

Image data compression

Image data such as binary mask image data is compressed by partitioning the data into blocks. An arithmetic encoder is initiated for each block and terminated at the end of the block. For each block, there is a fixed template/PDF table pair model which is chosen at the beginning of the block according to motion compensation and other inputs. One model has a template with spatially-correlating samples only, the other having both temporally and spatially-correlating samples. Estimations are made for values of samples which border the current block according to simple rules for the particular template.

Tommy Curran

Papers

Path allocation in a three-stage broadband switch with intermediate channel grouping

The strictly non-blocking condition for three-stage networks

Cell-level path allocation in a three-stage ATM switch

Image data compression

Compression of image data