In this paper a highly robust and efficient systematic-random linear network coding (S-RLNC) routing scheme is proposed. Unlike classic security systems, the proposed S-RLNC transmission model incorporates an advanced pre-coding and interleaving concept followed by multigeneration mixing (MGM) based data transmission to assure secure and QoS efficient communication. The proposed S-RLNC MGM based routing scheme exhibits higher throughput (99.5-100%) than the existing NCC-ARQ-WSN protocol (80%). Unlike NCC-ARQ-WSN, the proposed model incorporates multiple enhancements, such as RLNC concept, systematic network coding, MGM concept, IBF provision and redundant packet optimization. Combined, all these optimizations have strengthened the proposed S-RLNC MGM to exhibit optimum performance for secure and QoS-centric communication over WSNs.