Storage device and program

Abstract

Provided is a high speed searchable, high-capacity, and low-power storage device such as a CAM, a TCAM, or an associative memory. The storage device is provided with: a data storage unit in which a plurality of pieces of data are stored in association with addresses, respectively; an input unit to which search data is input; a search unit which has a plurality of comparison units for comparing the plurality of pieces of stored data stored in the data storage unit with the search data, the search unit searching for stored data corresponding to the search data; and an output unit for outputting the search result of the search unit. The search unit, the connection between the input unit and the search unit, and the connection between the search unit and the output unit are each constituted by an optical circuit. The plurality of comparison units of the search unit are connected in a daisy chain.

Claims

1. A storage device comprising: a data storage unit in which a plurality of data are stored, each associated with an address; an input unit into which search data is input; a search unit having a plurality of comparison units that compare the plurality of stored data stored in the data storage unit with the search data, and searching for stored data corresponding to the search data; and an output unit that outputs the search results of the search unit, wherein the search unit is composed of an optical circuit; the connection circuit between the input unit and the search unit and the connection circuit between the search unit and the output unit are each composed of an optical circuit; and the plurality of comparison units of the search unit are daisy-chained.

2. The storage device according to claim 1, wherein the search unit comprises a plurality of comparison units in which the plurality of comparison units are daisy-chained, the input unit is connected to each of the plurality of comparison units, the output unit is connected to each of the plurality of comparison units, and the plurality of comparison units are connected in parallel between the input unit and the output unit.

3. A storage device according to claim 1 or 2, characterized in that the input unit has a circuit that encodes the electrical signal of the search data and converts it into one or more optical signals of predetermined wavelengths.

4. A storage device according to any one of claims 1 to 3, wherein the output unit has a circuit that decodes the optical signal of the search result of the search unit and converts it into an electrical signal.

5. A storage device according to any one of claims 1 to 4, wherein the output unit determines one stored data to be output preferentially from the plurality of stored data when the search result of the search unit includes a plurality of stored data.

6. A storage device according to any one of claims 1 to 5, wherein the output unit outputs the stored data retrieved by the search unit, the address corresponding to the retrieved stored data, both the retrieved stored data and the address, or an index thereof.

7. A storage device according to any one of claims 1 to 6, characterized in that the storage device is a binary CAM (memory addressable by content) or a ternary CAM.

8. A storage device according to any one of claims 1 to 7, characterized in that the storage device is an associative memory.

9. A program for causing a computer or processor to function as a storage device according to any one of claims 1 to 8.

10. A program for causing a computer or processor to function as the search unit in any of claims 1 to 8 of the storage device.

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