Engineering Privacy by Design For Delay Tolerant Networks.

Delay Tolerant Network (DTN), represent a class of networks where continuous end-to-end connectivity may not be possible, and even when it does exists, then it is highly delayed or disrupted. DTN is a well recognized area in networking research and has attracted extensive attention from both network designers and application developers. Applications of this emerging communication paradigm are wide and include sensor networks, satellite and space communication and Rural Area DTN (RA-DTN) for providing connectivity in developing regions. The real challenge for DTN in general and RA-DTN in particular is to hide end user identities by providing a level of privacy through anonymity and pseudonymity. Privacy is a value shared by most human societies, and thus it is no longer an inherent assumption; rather it has becomes a property that must be explicitly designed. Privacy by Design (PbD) is a new paradigm to achieve privacy from the design level rather an add on functionality. This work engineered PbD and has accomplished privacy through Privacy by Architecture (PbA), Privacy by Resolution (PbR) and Privacy by Revocation (PbRe) mechanisms. This thesis proposes a privacy solution for DTN in three phases; where the first two phases incorporate PbA concept while the third phase is embedded with PbR and PbRe. The first phase, Pseudonym Credential Phase, allow users to generate a blinded Pseudonym Credential from a Verifying Certificate Authority (VCA), which verify user through digital certificate. Our approach is based on Blind Signature which prevents Certificate Authority from learning linking information about the user and content of the Pseudonym Credential. The second phase, Pseudonym Certificate Issuance Phase, facilitates users to anonymously authenticate to Issuing Certificate Authority (ICA) and obtained multiple Pseudonym Identities and Pseudonym Certificates. Our approach is based on the idea of embedding half resolution information directly in the Pseudonym Identity and the rest has been distributed in VCA and ICA. The third phase, Pseudonym Resolution and Revocation Phase, enforces several ICAs and VCA which further cooperates for pseudonym-identity resolution and revocation at legitimate situations without entrusting any one of them. The proposed protocols have been verified and validated through formal modeling in CasperFDR, also the study has employed an information theoretic quantification for different size of the system