We present the generic Dijkstra shortest path algorithm: an efficient algorithm for finding a shortest path in an optical network, both in a wavelength-division multiplexed network, and an elastic optical network. Our algorithm is an enabler of the real-time softwarized control of large-scale networks, and not only optical, we believe. The Dijkstra algorithm is a generalization of the breadth-first search, and we generalize the Dijkstra algorithm further to resolve the continuity and contiguity constraints of the frequency slot units. Specifically, we generalize the notion of a label, change what we iterate with, and reformulate the edge relaxation so that vertices are revisited, loops avoided, and worse labels discarded. We also used the typical constriction during edge relaxation to take care of the signal modulation constraints. The algorithm can be used with various spectrum allocation policies. We motivate and discuss the algorithm design, and provide our libre, high-quality, and generic implementation using the Boost Graph Library. We carried out 85000 simulation runs for realistic and random networks (Gabriel graphs) of 75 vertices with about a billion shortest-path searches, and found that the proposed algorithm outperforms considerably other three competing optimal algorithms, which are frequently used in research.

We present TECTLK, a logic to specify knowledge and real time in multi-agent systems. We show that the model checking problem is decidable, and we present an algorithm for TECTLK bounded model checking based on a discretisation method. We exemplify the use of the technique by means of the "Railroad Crossing System", a popular example in the multi-agent systems literature.

We investigate a SAT-based bounded model checking (BMC) method for MTL (metric temporal logic) that is interpreted over linear discrete infinite time models generated by discrete timed automata. In particular, we translate the existential model checking problem for MTL to the existential model checking problem for a variant of linear temporal logic (called HLTL), and we provide a SAT-based BMC technique for HLTL. We show how to implement the BMC technique for HLTL and discrete timed automata, and as a case study we apply the technique in the analysis of GTPP, a Generic Timed Pipeline Paradigm modelled by a network of discrete timed automata.

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