2 What is the difference between IPv4 and IPv6 addresses? Describes the IPv6 address representation

IPv4 uses 32-bit, 4-byte addresses, so there are only 4,294,967,296 addresses in the address space. However, some addresses are reserved for special purposes, such as private networks (about 18 million addresses) and multicast addresses (about 100 million addresses), which reduces the number of addresses that can be routed on the Internet.

IPv6 addresses are 128 bits, which is four times longer than IPv4 addresses. As a result, the IPv4 dotted decimal format is no longer applicable and is represented in hexadecimal format. IPv6 has three types of representation: hexadecimal notation, 0-bit compression notation, and embedded IPv4 address notation.

The physical address corresponding to the physical address of the storage unit in the physical address memory of the NIC is called the physical address, which corresponds to the logical address. The physical address of a network card is usually an EPROM (a flash memory chip that can usually be masked to be erased by a program) written to the network card by the network card manufacturer, and it stores the addresses that really identify the computer that sent the data and the host that received the data when it was transmitted.

Summary. Now, the vast majority of IP addresses we use are IPv4 addresses among them. However, with the continuous development of global IPv6 technology and the strong support of the state for IPv6 policy, IPv6 will definitely become the mainstream IP address protocol in the future.

With IPv6 networks, the device sending information has a permanent IP address, and the device type can be easily identified. IPsec also provides an authentication header service to ensure data confidentiality and consistency.

Pro, there are two major categories of IP addresses: IPv4 and IPv6, and the vast majority of IP addresses used are IPv4, which is the abbreviation of Internet Protocol Version 4, which represents the fourth version of the IP protocol. IPv6 represents the sixth version of the IP protocol, which is the next generation of the Internet protocol.

Right now, the vast majority of the IP addresses we use are IPv4 addresses in their stool slippery only. However, with the continuous development of global IPv6 technology and the strong support of the state for IPv6 policy, IPv6 will definitely become the mainstream IP address protocol in the future. After adopting the IPv6 network, the device that sends the information has a permanent IP address, and the device type is easy to identify.

IPsec also provides an authentication header service to ensure data confidentiality and consistency.

There are five types of IP addresses: Class A IP addresses, Class B IP addresses, Class C IP addresses, Class D IP addresses, and Class E IP addresses. Determine which type of IP address it belongs to by the range of IP addresses it belongs to.

1. Class A IP address.

A Class A IP address is one in which the first of the four segments of an IP address is the network number and the remaining three segments are the local computer number. If the IP address is represented in binary, the Class A IP address consists of a 1-byte network address and a 3-byte host address, and the highest bit of the network address must be "0".

The length of the network identity in the Class A IP address is 8 bits, the length of the host ID is 24 bits, and the number of Class A network addresses is small, with 126 networks, and each network can accommodate more than 16 million hosts.

2. A Class B IP address refers to the network number Huchen code in the first two segments of the IP address. If the IP address is represented in binary, the Class B IP address consists of a 2-byte network address and a 2-byte host address, and the highest bit of the network address must be "10".

The length of the network identity in the Class B IP address is 16 bits, and the length of the host ID is 16 bits, and the Class B network address is suitable for medium-sized networks, with 16,384 networks, and the number of computers that can be accommodated in each network is more than 60,000.

3. Class C IP address.

A Class C IP address refers to the number of the first three segments of the IP address that is the network number, and the remaining part of the number is the number of the local computer. If the IP address is represented in binary, the Class C IP address consists of a 3-byte network address and a 1-byte host address, and the highest bit of the network address must be "110".

In the Class C IP address, the length of the network identity is 24 bits, the length of the host ID is 8 bits, and the number of Class C network addresses is relatively large, with more than 2.09 million networks. Suitable for small-scale LANs with a maximum of 254 computers per network.

4. Class D IP address.

Historically, Class D IP addresses have been called multicast addresses, i.e., multicast addresses. In Ethernet, a multicast address names a set of sites that should be received by an application in that network.

The highest bit of a multicast address must be "1110", ranging from to.

5. Class E IP address.

Class E IP addresses start with "11110", and Class E IP addresses are reserved for future and experimental use. Ranges from to.

As with IPv4, the length of the prefix depends on the number of bits of the subnet mask provided by the provider.

In October 2008, the self-study exam "Computer Application Basics" real questions short-answer question 6.

IPv4: The IP address consists of 4 bytes (0 255) and a total of 32 bits.

Proofreading Answer:(1) 32 bits or 32 bytes or 4 bytes or 4 bytes.

2) 128 bits or 128 bytes or 16 bytes or 16 bytes.