Converging towards a timed LOTOS standard

Abstract Several ideas and proposals for an extension of the LOTOS ISO standard meant to support the specification of time parameters and time-dependent behaviours have appeared in the last few years. Some general requirements that such an extension should meet are identified, and a number of specific design options are discussed. Corresponding design decisions are then taken and motivated, leading to the definition of a Timed Basic LOTOS which attempts to promote convergence among the different existing proposals.