Prefix-PreservingIPAddressAnonymizationMeasurement-.pptVIP

Prefix-Preserving IP Address Anonymization:Measurement-based Security Evaluation and a NewCryptography-based Scheme Jun Xu, Jinliang Fan, Mostafa Ammar, Sue Moon College of Computing Sprint ATL Georgia Tech Overview Motivation IP address anonymization prefix-preserving Prefix-preserving anonymization canonical form TCPdpriv cryptography-based scheme Attacks models, analysis, evaluation Motivation Traces collected, to share or not to share? client personal privacy? commercial confidentiality? IP address anonymization → one to one mapping, consistent Prefix relationships among IP addresses? important: routing performance, clustering of end-systems Prefix-preserving anonymization → → preserve prefix correlation among addresses IP Address Anonymization Basic anonymization a: original 4-byte IP address a =a1 a2 … a32 a’: anonymized IP address a’=a’1a’2…a’32 F: 1-to-1 mapping function a’=F(a) Prefix preserving anonymization if a, b share k-bit prefix a1=b1,a2=b2, …, ak=bk, ak+1=bk+1 then a’=F(a), b’=F(b) share k-bit prefix a’1=b’1,a’2=b’2, …, a’k=b’k, a’k+1=b’k+1 Canonical Form Canonical construction of F using a series of fi a’i = ai ? fi-1(a1, a2, … , ai-1) f0 is a constant F is a prefix-preserving anonymization function A prefix-preserving anonymization function necessarily takes this form Different schemes use different fi Visualized as a tree Visualization: Address Space Visualization: Original Address Tree Visualization: Anonymization Function Visualization: Anonymized Address Tree TCPdpriv Sequentially scan IP address look up prefix in “history” table randomly choose suffix concatenate prefix,suffix; update “history” table TCPdpriv Sequentially scan IP address look up prefix in “history” table randomly choose suffix concatenate prefix,suffix; update “history” table New Crytography-Based Algorithm deterministic fi function trace-independent What PRF to use? Practical b