1. A method of network orchestration [
performed by a computing device] , the method comprising
, by an orchestrator:
obtaining a model of a physical resources part of a network , the physical resources part of the network comprising a plurality of physical resources, the model of the physical resources part of the network representing dependencies between different [ the ] physical resources in the physical resources part of the network;
obtaining a model of a virtualised resources part of the network, the virtualised resources part of the network comprising at least one virtualised network function, the model of the virtualised resources part of the network representing dependencies between different virtualised resources in the virtualised resources part of the network;
representing the network using [ generating ] a combined model of the network, the combined model of the network combining the model of the physical resources part of the network and the model of the virtualised resources part of the network,
wherein the combined model of the network models at least one performance-related variable related to an availability of at least one of the physical resources , and wherein the availability is determined using a mean time between failures (MTBF) and a mean time to recover (MTTR), and wherein the availability is equal to MTBF/(MTBF+MTTR) [ and at least one of the virtualized resources] ;
performing at least one optimisation operation using the combined model to identify an optimised mapping of the at least one virtualised network function onto at least one of the plurality of physical resources, the optimised mapping optimising the at least one performance-related variable; and
instantiating the at least one virtualised network function on the at least one of the plurality of physical resources based on the identified optimised mapping to optimise the at least one performance-related variable.
