Cabletron Systems Netlink FRX4000, User Manual

Page: 218 / 426

13-2 FRX4000/FRX6000 4.0 User Guide, Rev 01
IP networks are divided into classes, with this addressing scheme:
●
Class A allows up to 127 network numbers and several million node numbers:
Bit 0 is
0
, bits 1–7 are the network identifier, and bits 8–31 are the node iden-
tifier. In dotted decimal notation, the range of Class A addresses is
1.0.0.0–
127.255.255.255
.
.The valid range in FRX4000/6000 configuration is
1.0.0.0–
126.255.255.255
.
●
Class B allows up to approximately 16,000 network numbers, and approxi-
mately 65,025 node numbers: Bits 0–1 are
10
, bits 2–15 are the network iden-
tifier, and bits 16–31 are the node identifier. In dotted decimal notation, the
range of Class B addresses is
128.0.0.0–191.255.255.255
.
●
Class C allows up to approximately 2 million network numbers, and 255 node
numbers: Bits 0–2 are
110
, bits 3–23 are the network identifier, and bits 24–31
are the node identifier. In dotted decimal notation, the range of Class C
addresses is
192.0.0.0–223.255.255.255
.
If the node identifier is all zeroes, the overall 32-bit IP address refers specifically to
the network identified by the network identifier. If the node identifier is all ones, the
32-bit address refers to all hosts attached to the network. (This is the IP broadcast
address for that network.) If the entire 32 bits are ones, the address refers to all hosts
on the local network.
IP addresses are administered by Standford Research Institute’s Network
Information Center (NIC).
Network
Node
Network
Node
Network
Node