Wave Wireless Networking SPEEDLAN TM 6000, Руководство оператора

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SPEEDLAN TM
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Note: Non-public Addresses can include network address assigned from the network administrator or
from the IP provider. Also, there is one network in each class that is defined for private use, allowing
the creation of internal networks. These addresses are Class A: 10.0.0.0, Class B: 172.10.0.0, and
Class C: 192.168.0.0.
Subnetting a Network
The increasing number of hosts and networks make impractical address blocks that are not smaller
than 245. In order keep the IP address small, so routers can manage them without changing the
whole protocol, a smaller network definition is created. This is called a subnet. Subnets are intended to:
•
Reduce network traffic
•
Optimize performance
•
Simplify management
•
Create more effective and efficient addresses for large geographic distances
Default Subnet masks
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Class A: 255 .0.0.0
•
Class B: 255.255 .0.0
•
Class C: 255.255.255 .0
Note: Subnet mask is bolded .
What is a Subnet?
This term allows you to create multiple networks within one Class A, B, or C network. Each data link
(octet) contains its own unique identifier also known as the subnet. Also, each node on the same data link
must belong on the same subnet as well.
What is a Subnet Mask?
This term allows you to mask section(s) (depending on the class specified) of the octets in the network
address. Each octet used in the subnet mask is assigned to a data link. The leftover octet(s) are assigned to
the remaining nodes.
For more information on subnetting, see the example below and figure on the next page.
Example of Subnetting:
For example, a Class C network (255.255.255.0) contains three masked octets (255.255.255). The last
octet (0) is leftover for remaining nodes (i.e., computers).
If Router D is reading IP Addresses 195.172.3.1 (let’s call this IP Address 1) and 195.172.3.64 (let’s call
this IP Address 2) on this Class C network, it would send IP Address 1 to Subnet A and IP Address 2 to
Subnet B. The remaining nodes in each subnet (A through D) on this network can contain up to 254 pieces
of network equipment (computers, printers, fax machines, bridges or routers (also know as brouters), etc.).