DRES: Dynamic Range Encoding Scheme for TCAM Coprocessors

One of the most critical resource management issues in the use of ternary content addressable memory (TCAM) for packet classification/filtering is how to effectively support filtering rules with ranges, known as range matching. In this paper, a Dynamic Range Encoding Scheme (DRES) is proposed to significantly improve TCAM storage efficiency for range matching. Unlike the existing range encoding schemes requiring additional hardware support, DRES uses the TCAM coprocessor itself to assist range encoding. Hence, DRES can be readily programmed in a network processor using a TCAM coprocessor for packet classification. A salient feature of DRES is its ability to allow a subset of ranges to be encoded and hence to have full control over the range code size. This feature allows DRES to exploit the TCAM structure to maximize TCAM storage efficiency. DRES is a comprehensive solution, including a dynamic range selection algorithm, a search key encoding scheme, a range encoding scheme, and a dyn...

• Type: Journal
• Year: 2008
• Where: TC
• Authors: Hao Che, Zhijun Wang, Kai Zheng, Bin Liu
• Keywords: Dynamic Range, Information Technology, TC 2008, TCAM Coprocessor, TCAM Storage Efficiency