You are discussing the design and infrastructure of the Internet with several colleagues when a
disagreement begins over the actual function of the Tier System in the Internets design. What is
the function of the Tier System in the physical structure of the Internet?

A.
The Tier System provides the physical network with communication channels for the Internet
and voice/data applications.

B.
The Tier System provides a national interconnection of systems, called peering centers, to the
NAPs.

C.
The Tier System provides for a layered/hierarchical connection system of ISPs connecting to
the backbone.

D.
The Tier System provides for a connection point between an ISP and the backbone of the
Internet.

E.
The Tier System provides the actual connection point between a local user and the Internet.