This paper presents a system-level design methodology for networked embedded systems that exploits existing data-redundancy to increase their reliability. The presented approach not only supports a reliability-aware embedded system design from scratch, but also enables the redesign of existing systems to increase the reliability with a minimal communication overhead. The proposed approach contributes (a) algorithms to automatically identify inherent data-redundancy and (b) an automatic design space exploration that is capable of exploiting the revealed data-redundancy. A symbolic analysis is presented that quantifies the reliability of a system, enabling the usage of reliability as one of multiple conflicting optimization objectives. The proposed approach is applied to a realworld case study from the automotive area, showing a significantly increased reliability with a negligible communication overhead. Categories and Subject Descriptors C.4 [PERFORMANCE OF SYSTEMS]: Modeling techn...