IP Addressing
A-8 Vipersat CDM-570/570L User Guide

Private Network IP Addresses

RFC 1918 defines blocks of addresses for use on private networks:
•10.0.0.0 – 10.255.255.255
•172.16.0.0 – 172.31.255.255
•192.168.0.0 – 192.168.255.255

Network Address Translation (NAT)

Private networks can only connect to the public Internet by using a Network
Address Translation (NAT) device (a router, for example) or a proxy server
which has been assigned a public IP address. These network devices use a
public IP address to request information from the Internet on behalf of the
private IP addressed devices on the associated private network.
Figure A-5
NAT Router Example
This use of private addresses helps to conserve public IP addresses.
Subnets
Subnets can be defined as the further segmentation of the InterNIC assigned
Network ID IP address. The amount and type of subnetting performed by the
organization is determined by the network layout.
In the process of subnetting, bits are borrowed from the host ID portion of an IP
address and are then given to the network ID. Then a “Subnet Mask” gets
assigned to the host along with the IP address.
Ethernet
Host 1
Host 2
NAT Router
Internet
192.168.0.2
192.168.0.3
192.168.0.1 Public IP