Network Service Composition

Originally, the concept of network Slice is basically a set of Netowrk Services (NSs) as the following figure shows:

But as the concept evolved, the idea was to allow the multiple NSs to be connected among them in order to offer to the final user better services by creating a more complete and stronger service (Network Slice) deployment throught a composition of individual Network Services (NSs), similar to what it can be done within the NS with the Virtual network Functions that contains.