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Explain network classes.

43.Explain network classes.
Ans.
1. TCP/IP network are 4 bytes long, called IP addresses and written in dotted-decimal notation. (ex. 192.168.166.5)

2. The decimal numbers must be within the numeric range of 0-255, each IPv4 addresses consist of 4 parts.

3. Each part should conform to the 1-byte requirement.

4. Depending on the value of the first byte of the address, IP addresses can be divided into classes.

5. Network classes are of 3 type and have some specific range
Class A 0-127
Class B 128-191
Class C 192-233

6. Class division enables us efficient use of the address numbers.

7. Assigned network numbers are maintained in a database managed by InterNIC to insure that each assignment is unique.

8. After obtaining a network number, the host numbers may be assigned as required, for data transfer ARP maps the IP address to the MAC address of the device.

9. Routers are used for transferring data between 2 devices, routers are default gateway they must be configured.

10. Routers has an internal program called a routing table, which it uses to send the data to a host or another router.

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