This paper further develops the theory of constructing a fundamentally new class of system area networks – non-blocking dual photon networks with static self-routing. These net-works have scalability, high speed inherent in photon systems, and complexity comparable to a full switch. The use of an extended scheme basis (dual photon switches and separate photon multiplexers and demultiplexers) allows balancing the scalability-speed and complexity-speed ratios. This paper proposes a method for constructing a two-stage fault-tolerant dual network with the indicated properties based on networks with the quasi-complete graph and quasi-complete digraph topologies and the invariant extension method with internal parallelization.