1. How many physical links, data links, and routes are there along the way when Host A sends a packet to Host D using the shortest path?
2. How many physical links, data links, and routes are there along the way when Host A sends a packet to Router R2 using the shortest path? (Assume that hops will be minimized across switches and routers.)
3. How many physical links, data links, and routes are there along the way when Host D sends a packet to Host B using the shortest path?

Switched Network X FrameX et Switch X3 Data Link A-R1 Host A Host C Physical ink (A-X1) Switch X4 Switch X1 Network Y Router R1 Switch X2 Route A-B Data Link Route A-B 3 Networks (X,YZ) 1 Packet & Route 3 Frames& Data Links 7 Physical Links R1-R2 Packet Frame Y Switched Network Z Host B Switch Z1 Router R2 Frame Z itch Data Link R2-B Switch Z3 Router R3 Switch Z4 Host D Host E FIGURE 1-28 An Exercise in Physical, Links, Data Links, and Routes