D-Link DI-304M manual Subnet Mask

Models: DI-304 DI-304M

1 105
Download 105 pages 37.76 Kb
Page 97
Image 97

DI-304/DI-304M ISDN Remote Router

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

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

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.

89

Page 97
Image 97
D-Link DI-304M manual Subnet Mask