Windows Network Programming Chinese Note (ii)

IPV4 Address Segment

IPV4 Address Category

Kinds	Network section	1th Digit	Endpoint Number
A	8 Guests	0-127	16777216
B	16 Guests	128-191	65526
C	24 Guests	193-223	256
D	N/A	224~239	N/A
E	N/A	240~255	N/A

1. Class A Address
(1) The 1th byte of the Class A address is the network address, and the other 3 bytes are the host address.
(2) Class A address range: 1.0.0.1-126.255.255.254
(3) Private address and reserved address in Class A address:
①10.x.x.x is a private address (the so-called private address is not used on the Internet, but is used in the local area network address).
Range (10.0.0.0-10.255.255.255)
②127.X.X.X is a reserved address for use as a cyclic test.

2. Class B Address
(1) Class B addresses 1th and 2nd bytes are network addresses, and the other 2 bytes are host addresses.
(2) Class B address range: 128.0.0.1-191.255.255.254.
(3) Private address and reserved address of Class B address
①172.16.0.0-172.31.255.255 is a private address
②169.254.X.X is a reserved address. If your IP address is automatically getting an IP address, and you do not find an available DHCP server on the network. You will get one of the IPs.

3. Class C Address
(1) Class C addresses the 1th byte, the 2nd byte, and the 3rd byte are the network addresses, and the 4th bytes are the host addresses. The first three bits of the 1th byte are also fixed to 110.
(2) Class C address range: 192.0.0.1-223.255.255.254.
(3) Private address in class C address:
192.168.x.x is a private address. (192.168.0.0-192.168.255.255)

4. Class D Address
(1) The Class D address does not divide the network address and the host address, its 1th byte of the first four bits fixed to 1110.
(2) Class D address range: 224.0.0.1-239.255.255.254

5. Class E Address
(1) The E-class address does not divide the network address and the host address, its 1th byte of the first five bits fixed to 11110.
(2) Class E address range: 240.0.0.1-255.255.255.254

The problem of IP network segment is related to the subnet mask.

The IP address segment of the standard subnet mask is easier to identify, as long as the same subnet mask, the network is the same network segment.
For example, 192.168.10.5 and 192.168.10.220, if both are standard 255.255.255.0 subnet masks, indicate that two IP address 192.168.10 is a network segment and two IP is in a unified network segment.

If it is a non-standard subnet mask, it needs to be calculated, or for example 192.168.10.5 And 192.168.10.220 These two IP, if the subnet mask is 255.255.255.240, indicates that the standard subnet mask borrowed 4 bits, the network segment width is 16, that is 192.168.10.5 in 192.168.10.0 this segment, and 192.168.10.220 in 19 2.168.10.192 this network segment.

Windows Network Programming Chinese Note (ii)