With the continuous development of the Internet, the use of IPv6 addresses is becoming more and more widespread. For some network administrators or ordinary users, it is an important issue to determine whether an IPv6 address is a public or private address. Here are some common methods to help you determine the type of IPv6 address.
1. Static judgment.
1.Scope judgment.
The range of public IPv6 addresses is unique and usually starts with 2001, while private IPv6 addresses are assigned by local administrators and usually start with fe80. Therefore, you can check the prefix of an IPv6 address to determine whether it is a public or private address.
2.Route judgment.
Public IPv6 addresses can be routed through public routers, while private IPv6 addresses can only be routed on the local network. Therefore, you can use a tool such as traceroute to test the reachability of an IPv6 address, if it can be reached, it means that it is a public address, otherwise it is a private address.
3.DNS queries.
You can query DNS records to determine whether an IPv6 address is on the public or private network. If there is an AAAA record for the IPv6 address in the DNS record, it is a public IP address, otherwise it is a private IP address.
2. Dynamic judgment.
1.Network scanning.
Use the network scanning tool to scan the IPv6 address range of the target network to find out which addresses are active public and private addresses. For example, scanning with a tool such as nmap can get a list of active IPv6 addresses on the target network.
2.Network snooping.
By deploying sniffers or servers in the network to listen for network traffic, it is possible to discover which IPv6 addresses are using the network. By analyzing the monitored packets, you can determine which are public and private addresses.
3.Third-Party Services.
There are some third-party services that can provide IPv6 address classification and location functions, such as WHOIS lookup, IP geolocation query, etc. These services can help you quickly determine whether an IPv6 address is public or private.
In summary, there are several ways to determine whether an IPv6 address is public or private. For network administrators and regular users, mastering these methods can help them better manage and use IPv6 network resources.