An IP address can identify any network or monitoring device in the same network. To identify other networks or devices in it, it is determined based on the classification of these IP addresses. According to the size of the network where the node monitors the device, the IP address is generally divided into three categories: A, B, and C (the default network mask is determined based on the first field in the IP address).
A type IP address
Class A addresses are represented in the range of 1.0.0.1 to 126.255.255.255. The default subnet mask is: 255.0.0.0. Class A addresses are mostly allocated to larger networks. Class A networks use the first set of numbers to represent the address of the network itself, and the last three sets of numbers serve as the addresses of devices connected to the network. Assigned to a large network with a large monitoring system host and a small number of local area networks. For example, private large-scale network architecture. E.g:
127.0.0.0 to 127.255.255.255 are reserved addresses and are used for loop testing.
0.0.0.0 to 0.255.255.255 are also reserved addresses and are used to represent all IP addresses.
A class A IP address consists of a network address of 1 byte (each byte is 8 bits) and a 3-byte device address. The highest bit of the network address must be "0", that is, the first digit range is 1 to 1. 127. Each Class A address can theoretically connect to 16777214<256×256×2256 devices. The network has 126 available Class A addresses. This type of address is suitable for large network architectures.
Class B IP addresses Class B addresses are represented in the range of 128.0.0.1 to 191.255.255.255. The default subnet mask is 255.255.0.0. Class B addresses are generally assigned to medium-sized networks. Class B networks use the first and second groups of numbers to represent the addresses of the network, and the latter two groups of numbers represent the host addresses on the network. For example: 169.254.0.0 to 169.254.255.255 are reserved addresses. If the IP address is obtained automatically and there is no available DHCP server on the network, an IP address will be temporarily obtained from 169.254.0.0 to 169.254.255.255. A class B IP address consists of a 2-byte network address and a 2-byte host address. The highest bit of the network address must be "10", that is, the first digit range is 128-191. Each Class B address can connect to 65534 (2^16) devices, and the network can have 16383 (2^14-1) Class B addresses (because Class B network address 128.0.0.0 is not assigned).
Class C IP address
The range of the Class C address is: 192.0.0.1~223.255.255.255, and the default subnet mask is: 255.255.255.0. Most of the Class C addresses are allocated to small networks. For example, the number of devices that can be connected is At the very least, the network segment is divided into several segments for management. A class C network uses the first three groups of numbers to represent the network's address, and the last group of numbers serves as the host address on the network. A class C address consists of a 3-byte network address and a 1-byte host address. The highest bit of the network address must be "110", that is, the first digit range is 192-223. Each C-class address can be connected to 254 devices, and there can be 2097152 C-type address segments 532676608 addresses on the network.
In particular, RFC 1918 has reserved 3 IP address spaces (1 A-type address segment, 16 B-type address segments, and 256 C-type address segments) as private internally used addresses. The IP address in this range cannot be routed to the Internet backbone network. Once it appears, the network router will automatically exclude the use of this private address. The range of private private addresses that cannot be planned on the route within the IP address category that belongs to RFC 1918 is:
Class A is from 10.0.0.0 to 10.255.255.255;
Class B consists of 172.16.0.0 to 172.31.255.255;
The C class is from 192.168.0.0 to 192.168.255.255.
In the use of private addresses to connect the Internet to the Internet, you need to convert private addresses to public addresses. This conversion process, commonly referred to as network address translation (NAT), usually uses routers to perform NAT translation on large-scale monitoring systems to facilitate the massive monitoring of the use of private IP addresses.
In fact, IP network addresses still have D address and E class two address planning methods. However, these two types of addresses are of special use. Here, I will only give a brief introduction: Class D addresses are not divided into network addresses and host addresses. The first four bits of the first byte are fixed at 1110. Class D address range: 224.0.0.1 to 239.255.255.254. Class D addresses are used for multicasting. Class D addresses are called broadcast addresses and are used by special protocols to send information to selected nodes. Class E address rules are reserved for future use.
Every device connected to the monitoring network, regardless of its IP address belongs to a category, is equal to the status of other devices or host servers in the network. Since only the IP address is the unique identifier of the distinguished host or camera device, the above classification of IP addresses applies only to the network architecture classification. In a network, a host server or NVR can have one or more IP addresses, just as one person can have multiple communication addresses, but two or more servers or NVRs and cameras cannot share an IP address. If the IP addresses of the two computers are the same, an exception such as a network IP collision will occur, and neither device will work properly.
A type IP address
Class A addresses are represented in the range of 1.0.0.1 to 126.255.255.255. The default subnet mask is: 255.0.0.0. Class A addresses are mostly allocated to larger networks. Class A networks use the first set of numbers to represent the address of the network itself, and the last three sets of numbers serve as the addresses of devices connected to the network. Assigned to a large network with a large monitoring system host and a small number of local area networks. For example, private large-scale network architecture. E.g:
127.0.0.0 to 127.255.255.255 are reserved addresses and are used for loop testing.
0.0.0.0 to 0.255.255.255 are also reserved addresses and are used to represent all IP addresses.
A class A IP address consists of a network address of 1 byte (each byte is 8 bits) and a 3-byte device address. The highest bit of the network address must be "0", that is, the first digit range is 1 to 1. 127. Each Class A address can theoretically connect to 16777214<256×256×2256 devices. The network has 126 available Class A addresses. This type of address is suitable for large network architectures.
Class B IP addresses Class B addresses are represented in the range of 128.0.0.1 to 191.255.255.255. The default subnet mask is 255.255.0.0. Class B addresses are generally assigned to medium-sized networks. Class B networks use the first and second groups of numbers to represent the addresses of the network, and the latter two groups of numbers represent the host addresses on the network. For example: 169.254.0.0 to 169.254.255.255 are reserved addresses. If the IP address is obtained automatically and there is no available DHCP server on the network, an IP address will be temporarily obtained from 169.254.0.0 to 169.254.255.255. A class B IP address consists of a 2-byte network address and a 2-byte host address. The highest bit of the network address must be "10", that is, the first digit range is 128-191. Each Class B address can connect to 65534 (2^16) devices, and the network can have 16383 (2^14-1) Class B addresses (because Class B network address 128.0.0.0 is not assigned).
Class C IP address
The range of the Class C address is: 192.0.0.1~223.255.255.255, and the default subnet mask is: 255.255.255.0. Most of the Class C addresses are allocated to small networks. For example, the number of devices that can be connected is At the very least, the network segment is divided into several segments for management. A class C network uses the first three groups of numbers to represent the network's address, and the last group of numbers serves as the host address on the network. A class C address consists of a 3-byte network address and a 1-byte host address. The highest bit of the network address must be "110", that is, the first digit range is 192-223. Each C-class address can be connected to 254 devices, and there can be 2097152 C-type address segments 532676608 addresses on the network.
In particular, RFC 1918 has reserved 3 IP address spaces (1 A-type address segment, 16 B-type address segments, and 256 C-type address segments) as private internally used addresses. The IP address in this range cannot be routed to the Internet backbone network. Once it appears, the network router will automatically exclude the use of this private address. The range of private private addresses that cannot be planned on the route within the IP address category that belongs to RFC 1918 is:
Class A is from 10.0.0.0 to 10.255.255.255;
Class B consists of 172.16.0.0 to 172.31.255.255;
The C class is from 192.168.0.0 to 192.168.255.255.
In the use of private addresses to connect the Internet to the Internet, you need to convert private addresses to public addresses. This conversion process, commonly referred to as network address translation (NAT), usually uses routers to perform NAT translation on large-scale monitoring systems to facilitate the massive monitoring of the use of private IP addresses.
In fact, IP network addresses still have D address and E class two address planning methods. However, these two types of addresses are of special use. Here, I will only give a brief introduction: Class D addresses are not divided into network addresses and host addresses. The first four bits of the first byte are fixed at 1110. Class D address range: 224.0.0.1 to 239.255.255.254. Class D addresses are used for multicasting. Class D addresses are called broadcast addresses and are used by special protocols to send information to selected nodes. Class E address rules are reserved for future use.
Every device connected to the monitoring network, regardless of its IP address belongs to a category, is equal to the status of other devices or host servers in the network. Since only the IP address is the unique identifier of the distinguished host or camera device, the above classification of IP addresses applies only to the network architecture classification. In a network, a host server or NVR can have one or more IP addresses, just as one person can have multiple communication addresses, but two or more servers or NVRs and cameras cannot share an IP address. If the IP addresses of the two computers are the same, an exception such as a network IP collision will occur, and neither device will work properly.
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