Efficient Gray Code Based Range Encoding Schemes for Packet Classification in TCAM
Author: Yeim-Kuan Chang, Cheng-Chien Su, and Yung-Chieh Lin
Publisher: Submit to Transactions on Computers
Presenter: Chun-Yi Li
Date: 2008/12/24
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Outline Preliminary
Related Works
EIGC
Perfect-BRGC (P-BRGC)
Performance
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PreliminaryBuddy Code & BRGC :
Elementary interval
Related WorksDatabase independent & database dependentDirect range-to-prefix conversion:
Database independent schemeConvert each range to prefixes
ex:R=[1,14] prefix = 0001, 001*, 01**, 10**, 110*, 1110Ternary string(Boolean expression)
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Related Works
Elementary interval based encoding
R1=0101, 0110 R2=0001R3=01** R4=0011, 010*
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Related WorksParallel packet classification encoding
Proposed Range Encoding Scheme
Scheme based on Elementary Interval and BRGC (EIGC)
Assign each elementary interval a identifier by using BRGC
Default elementary interval have the same code.
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Proposed Range Encoding Scheme
Scheme based on Perfect BRGC Range Sets (P-BRGC)Definition1:Any range in the set must intersect at least
one of the other ranges
Definition2:A perfect BRGC range sets satifies
(1)Each range contain 2n elementary intervals
(2)Two intersection range A and B in the set, share elementary interval must be
equal to half of the number of elementary interval contained in either A or B.
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Perfect BRGC range sets
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Perfect BRGC range sets
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Virtual endpoint insertShould limit the number of virtual endpoints
Perfect BRGC range sets
Insert a range into layers
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Performance
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Performance
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Performance – All rules
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Performance - Non-prefix rules
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