Performing lookup operations on associative memory entries

Details Performing lookup operations on associative memory entries Performing lookup operations on associative memory entries

2007-06-26

2007-06-26

Farrokh, Hashem (Department: 2187)

Electrical computers and digital processing systems: memory

Storage accessing and control

Specific memory composition

C365S049130

Reexamination Certificate

active

11321918

ABSTRACT:
Methods and apparatus are disclosed for performing lookup operations using associative memories, including, but not limited to modifying search keys within an associative memory based on modification mappings, forcing a no-hit condition in response to a highest-priority matching entry including a force no-hit indication, selecting among various sets or banks of associative memory entries in determining a lookup result, and detecting and propagating error conditions. In one implementation, each block retrieves a modification mapping from a local memory and modifies a received search key based on the mapping and received modification data. In one implementation, each of the associative memory entries includes a field for indicating that a successful match on the entry should or should not force a no-hit result. In one implementation, an indication of which associative memory blocks or sets of entries to use in a particular lookup operation is retrieved from a memory.

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