186-128=58    1
64	      0
58-32=26      1
26-16=10      1
10-8 = 2      1
4	      0
2-2=0         1
1             0
1011 1010

Broadcast address == nework number + all 1's in host field
128.186.0.0  128.186.255.255
128.186.12.0/24  128.186.12.255
128.186.24.4/30  128.186.24.7

ARP =  Known IP, ask for MAC
RARP = known MAC, ask for IP
BootP = present MAC, ask for IP and OS
DHCP = know MAC, ask for IP and other protocol information
PPP = login,get authetication, obtain IP if needed