正解:B
Traditional WANs are characterized by centralized reachability, security, and application policies. This means that the WAN is managed from a central location, allowing for consistent policy enforcement and simplification of the network structure. Traditional WANs do not operate over DTLS and TLS tunnels; instead, they rely on dedicated leased lines, MPLS, or other types of connections that provide point-to-point connectivity. The data plane and control plane are typically integrated in traditional WAN devices, such as routers, which handle both forwarding data packets and the routing protocols that manage path selection.
References:
* Traditional WAN Design Summary - Cisco1
* The 2015 Guide to WAN Architecture & Design - Cisco2
* Traditional WAN vs. SD-WAN: Everything You Need to Know3