Cabletron Systems EMM-E6 Ethernet Manual De Usuario

Table 1-2. Class A

Table 1-3. Class B

Table 1-4. Class C

Range of Network IDs: 

1 - 126. host. host. host
[1 octet for the Network ID 
(127 reserved)] 

Binary translation:
(of first octet)

0000001 - 01111111
[first bit is always 0]

Range for the Host ID:

net. 1 - 254. 1 - 254. 1 - 254
[3 octets for the Host ID - allows 
16,777,214 hosts per network]

Range of Network IDs: 

128 - 191. 1 - 254. host. host
[2 octets for the Network ID]

Binary translation:
(of first octet)

1000000 - 10111111
[first bit is always 1 and second 
is always 0]

Range for the Host ID:

net. net.1 - 254. 1 - 254
[2 octets for the Host ID - allows 
65,534 hosts per network]

Range of Network IDs: 

192 - 223. 1 - 254. 1 - 254. host
[3 octets for the Network ID]

Binary translation:
(of first octet) 

1100000 - 11011111
[first and second bits always 1 
and third is always 0]

Range for the Host ID:

net. net. net. 1 - 254
[1 octet for the Host ID - allows 
254 hosts per network]

CH1Book  Page 24  Wednesday, March 20, 1996  7:48 AM