IPV4 address division
IPV4 address: It is composed of 32 in binary format. In order to facilitate the distinction, convert 32-bit binary into decimal number, separated by dots, similar to 192.168.1.0
Address classification: ABCDE
Class ABC address: unicast address
Class D address: multicast address
Class E address: reserved address
The most widely used address is the ABC three types of addresses
These addresses are divided into the following categories:
1-126 A类
128-191 B类
192-224 C类
224-239 D类
240-255 E类
Class A address subnet mask 255.0.0.0
Class B address subnet mask 255.255.0.0
Class C address subnet mask 255.255.255.0
Special IP address:
1:127 Loopback address 127.0.0.1 The virtual network card of the computer system tests whether the network of the local system is working properly
2: 0.0.0.0 can represent the default or invalid address
3: 25.255.55.255 restricted (router) broadcast address
4: The host bits are all 0
network numbers, indicating a network segment, not a configurable IP address.
Network number abbreviation: 192.168.1.0 255.255.255.0 =192.168.1.0/24
5: The host bits are all 1
192.168.1.255/24=192.168.1.11111111/24 The direct broadcast address is not a configurable IP address
6: 169.254.0.0/16 local link address
because the gateway did not automatically assign the IP address to the computer, so the computer automatically configures its own IP address. If you can't access the Internet, check if your computer's IP address starts with 169.254, which is wrong. I turned off DHCP and turned it on again, creating an IP address
7. Subnet division
By extending the length of the subnet mask, borrow bits from the host bit to the network bit; logically divide a network segment number into multiple
For example: 192.168.1.0
11000000 10101000 00000001 00000000
borrows two host bits for the network bit, and extends the network bit to 26 bits,
then the two bits borrowed can be divided into four bits 00 01 11 10, that is, four subnets in the
future These 4 subnets can be used for four small network segments in a large network segment, and they can be allocated reasonably and perform
their own duties.
8: CIDR-classless inter-domain routing—take the same bit, go to the different bit
Subnet summary: After summary, the mask length of the summary address is greater than or equal to the main class.
Supernet: After summary, the mask length of the summary address is less than the main class;
How to configure the IP when experimenting
Huawei's basic configuration commands
<Huawei> 用户模式 可以查看所有的设备参数
<Huawei>system-view 键入系统视图命令
[Huawei] 系统模式 可以对设备进行管理
[Huawei—？？？] 其他模式；各种专用配置模式
Quit 一层一层退
display this 查看在该位置配置的所有命令
[Huawei]display current-configuration 查看该设备上所有的配置命令
[Huawei]interface GigabitEthernet 0/0/0 进入某个接口
[Huawei-GigabitEthernet0/0/0]ip address 192.168.1.1 255.255.255.0 配置ip地址
[Huawei-GigabitEthernet0/0/0]quit 退出该模式
[Huawei]display ip interface brief 查看接口摘要