Computer Science Homework Help

question like these:

Problem 1 (20 points). Regarding Internet protocol stack:
(a) specify the principal responsibilities of each layer. (10 points)
(b) how an end system (host), a router, a switch, and a hub differ according to the layered architecture?
(5 points)
(c) name at least one protocol corresponding to each layer (except for the physical layer). (5 points)

Specify whether the following MAC addresses are unicast, multicast, or broadcast.
Why?
(a) ff:ff:ff:ff:ff:ff
(b) 52:54:00:ac:f2:02
(c) b9:31:9a:82:6b:51
(d) 37:7a:ff:61:9c:42
(e) 46:69:29:1a:fe:ee

Consider the following extended service set. Suppose A wants to send a frame to
B. Specify all addressing fields in each step (depicted by an arrow) of communication.