The TCP/IP networking model has four layers, namely,
- Application layer,
- Transport layer,
- Internet layer and
- Network access layer.
The network access layer is the equivalence of the physical and data-link layer in the OSI model. The unmanaged switch transmits frame in the collision domain and the wireless access point allows a collision free frame transfer between nodes. The frame and means of transmission are related to the network access layer of the TCP/IP model.
The Internet layer is an equivalence of the network layer in the OSI model, this is where the ip address is used to communicate within and to remote networks. The router is used to determine a path for packets to destination workstations. The firewall is used to stop unwanted packets from accessing a network. Packets are related to internet layer, so the router and firewall are operational in layer 2, internet layer.
in the 4th century there were about 100k citizens. only about 40k could participate in the democratic process ( this is only if the question is referring to ancient democracy )
