General DataComm SpectraComm IP T1, Руководство по установке и эксплуатации

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Application Guidelines IP Addresses
A-8 SpectraComm IP T1 Router Card 076R200-000
Installation and Operation Manual Issue 13
Network Classifications
IP addressing uses a set of fixed structure addresses known as classes (A,B, C, D, and E). An
internet address can be acquired by sending a request to the Internet Network Information Center
or from an Internet Service Provider.
Table A-3 describes network classes. Note that a message sent
to a Class D address is received by all the devices sharing that address.
RFC 1918 has reserved some addresses for private Internet Addressing. In order to use these private
IP addresses, you must use a firewall, Network Address Translator, or proxy server to connect to
the Internet. These devices convert the private address into a legitimate Internet address.
Table A-4
and the associated figure illustrate private addressing for a full Class A network, 16 contiguous
Class B networks and 256 contiguous Class C networks.
.
Table A-3 Network Classification
NTWK
Class
First Octet
Range of
Networks
Default Mask Example Description
A 1 - 126 1.0.0.0 - 127.0.0.0 255.0.0.0 18.0.172.16
Class A, B and C
addresses are used to
address: hosts, hubs,
switches, routers and other
IP devices.
Class A: 127 is reserved for loopback
B 128 - 191 128.0.0.0 -
191.255.0.0 255.255.0.0 140.250.16.1
C 192 - 223 192.0.0.0 -
223.255.255.0 255.255.255.0 200.10.20.10
D 224 - 239 224.0.0.0 -
239.255.255.255 255.255.255.255 224.0.0.9 Class D addresses are
used for multi-cast IP or
group addresses.
E Class E: Reserved
Note
Class D addresses are used in video teleconferencing, Network Time Protocol, some routing protocols
(i.e., RIPv2 and OSPF), and some mass push installation programs. Class D traffic can be routed through
an IP network if configured with DVMRP, PIM or MOSPF
Table A-4 Private IP Addressing
Network Class Private RFC 1918 Addresses
A 10.0.0.0 - 10.255.255.255
B 172.16.0.0 - 172.31.255.255
C 192.168.0.0 - 192.168.255.255
ROUTER
NETWORK
172.16.0.0
INTERNET
172.16.2.2 172.16.2.4
172.16.1.2 172.16.1.4
PORT 1
172.16.2.1
PORT 2
172.16.1.1