What are the reasons for the internet adopting a layered network architecture, and what are the benefits of this design?

$2.$ Layer headers Refer to the figure below, which is similar to the one from Lecture $0.$ In this example, Host A sends one packet to host B at time t $=0.$ In this question, we explore how the packet header changes as the packet traverses different layers and protocols of the network. At each time step, fill in the empty blocks to describe which headers are attached to the payload. The packet headers are provided at time t $=2$ for reference.