What defines a Packet Switch Network (PSN)?

A Packet Switch Network (PSN) is fundamentally characterized by its ability to transmit data packets over a network, as opposed to using traditional circuit-switching methods. This means that data is broken down into discrete packets which are then sent over the network independently. Each packet can take different paths to its destination, where they are reassembled in the correct order.

The primary function of a PSN is to provide efficient and versatile tactical data connectivity, which is key in military and advanced communication systems. This method of data handling enables more efficient use of the available bandwidth, allows for scalable network design, and supports robust data communication that is essential in various operational contexts.

While other options mention relevant aspects of networks, they do not encapsulate the essential characteristic of a PSN. For instance, a network primarily designed for voice communications or one that handles video streaming lacks the foundational principle of packet switching. Likewise, while managing multiple service types is a feature of many modern networks, it does not specifically define the packet switching capability that is central to a PSN. Therefore, the definition that aligns accurately with the operational principles of a Packet Switch Network is the one focusing on tactical data connectivity using packets.