Methods and apparatus for mapping ranges of values into unique values of particular use for range matching operations using an associative memory
US6717946B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 2002 |
| Grant date | Apr 6, 2004 |
| Priority date | — |
| Expiry date | Nov 6, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/90344
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Methods and apparatus are disclosed for maintaining one or more ranges and identifying whether a value matches one of the ranges and optionally which range is matched. One implementation includes a range programming engine for generating one or more mapped subtrie values identifying each range, each of the mapped subtrie values identifying a different subset of the range. An associative memory stores the mapped subtrie ranges. A mapping engine receives a particular value and generates a lookup word including a mapped representation of the particular value. The associative memory performs a lookup operation to identify whether or not the particular value is within one of the ranges. In this manner, only a small number of associative memory entries are required to identify whether a mapped particular value falls within the range. The particular range matched can be identified such as by a read operation in an adjunct memory based on the address of the matching entry.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.