Справочник Пользователя для Technicolor - Thomson 210i

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SpeedTouch 210i 
 
70
different for each IP device — or, to be more precise, each IP-capable port or 
interface — connected directly to that network. 
 
The network portion of an IP address will be referred to in this manual as a network 
number
; the host portion will be referred to as a host number
 
To connect to the Internet or to any private IP network that uses an Internet-assigned 
network number, you must obtain a registered IP network number from an Internet-
authorized network information center. In many countries you must apply through a 
government agency, however they can usually be obtained from your Internet Service 
Provider (ISP). 
 
If your organization's networks are, and will always remain, a closed system with no 
connection to the Internet or to any other IP network, you can choose your own network 
numbers as long as they conform to the above rules. 
 
If your networks are isolated from the Internet, e.g. only between your two branch offices, 
you can assign any IP Addresses to hosts without problems. However, the Internet 
Assigned Numbers Authority (IANA) has reserved the following three blocks of IP 
Addresses specifically for private (stub) networks: 
Class 
Beginning Address 
Ending Address 
10.0.0.0 
10.255.255.255 
172.16.0.0 
172.31.255.255 
192.168.0.0 
192.168.255.255 
 
It is recommended that you choose private network IP Addresses from the above list. For 
more information on address assignment, refer to RFC 1597, Address Allocation for 
Private Internets
 and RFC 1466, Guidelines for Management of IP Address Space
 
Subnet Mask 
In the absence of subnetworks, standard TCP/IP addressing may be used by specifying 
subnet masks as shown below. 
 
IP Class 
Subnet Mask 
Class A 
255.0.0.0 
Class B 
255.255.0.0 
Class C 
255.255.255.0 
 
Subnet mask settings other than those listed above add significance to the interpretation of 
bits in the IP address. The bits of the subnet mask correspond directly to the bits of the IP 
address. Any bit an a subnet mask that is to correspond to a net ID bit in the IP address 
must be set to 1.