What are the differences between the DiffServ and IntServ models?

The DiffServ model is designed to handle network traffic in a way that allows for efficient management of various service levels without needing to track the status of each individual flow. In this model, packets are classified and marked at the network's edge, enabling routers and switches throughout the network to handle them according to pre-defined service levels. This classification leads to reduced complexity and overhead since it only requires the differentiation of traffic types rather than maintaining detailed state information for every active flow.

In contrast, the IntServ (Integrated Services) model does maintain the status of each flow, as it establishes and maintains a state for every connection that requires guaranteed quality of service. This inherent complexity limits its scalability, making it less suitable for handling large volumes of traffic compared to the DiffServ model.

The other aspects mentioned may refer to characteristics associated with either model. For instance, while the DiffServ model can serve different kinds of traffic, such as voice and video, this is in terms of prioritization rather than providing different services for varying destinations. DiffServ is indeed suited for large-scale backbone networks, but this characteristic is not the reason it operates without tracking flow status, which is central to understanding why answer choice C is the correct one.