フリー問題

問題文

The reference architecture for network functions virtualization is usually described as three working domains. Which grouping is correct?

選択肢

1. The application layer, the control layer and the infrastructure layer, connected by an interface that faces upward toward the applications and another that faces downward toward the devices, which together allow a central element to program the behavior of the whole network.
2. The tenant domain, the provider domain and the transit domain.
3. The virtualized network functions themselves, the infrastructure that hosts them, and the management and orchestration that drives their life cycle.
4. Compute, storage and network, each supplied by a separate provider, so the architecture says nothing about who drives the life cycle of a function and breaks as soon as one provider supplied two of the three.