Method For Paramaterized Application Specific Integrated Circuit (ASIC)/Field Programmable Gate Array (FPGA) Memory-Based Ternary Content Addressable Memory (TCAM)

摘要

A method and apparatus for providing TCAM functionality in a custom integrated circuit (IC) is presented. An incoming key is broken into a predefined number of sub-keys. Each sub-key is sued to address a Random Access Memory (RAM), one RAM for each sub-key. An output of the RAM is collected for each sub-key, each output comprising a Partial Match Vector (PMV). The PMVs are bitwise ANDed to obtain a value which is provided to a priority encoder to obtain an index. The index is used to access a result RAM to return a result value for the key.