The demand for IP addresses has outstripped the number available through the current IPv4 protocol, which has a 32-bit IP address length and a maximum of 2^32-1 addresses. The main reason for this shortage is the way IP addresses are currently being used, which limits the number available to the network. The IPv6 protocol is being developed to address this problem by providing more public IP addresses.

Currently, public IP addresses are highly valuable, as they can be used to set up servers and secure encrypted tunnels. In some cases, the cost of a 20M fixed public IP can be up to 40000/year, while the cost of a 100M broadband (non-fixed IP) can be as low as 8000/year. Some companies have made significant profits by obtaining public IP addresses and remaining quiet about it.

One solution to the shortage of IP addresses is the use of multi-layer NAT technology, which can alleviate the issue both in theory and in practice. The question of IP address shortages is an important one, and finding effective solutions will be key to addressing the issue.

While 1:N NAT technology allows hosts behind NAT to access the internet, it does not allow hosts on the internet to access hosts behind NAT. To enable this, you need to configure static NAT, which requires additional configuration on each layer. The more layers there are, the greater the configuration workload.

Furthermore, hosts behind NAT that are accessed by internet users often provide HTTP services, which typically use port 80. However, a public IP address can only offer one port, so companies that need to deliver HTTP services may require a larger public IP address pool.

Multi-layer NAT can help alleviate the shortage of IP addresses, but a significant public IP address pool is still necessary for customers with public IP addresses. In terms of IP quality, resource quantity, and service capability, MaxProxy IP is a reliable choice for domestic proxy IP services and can provide a good user experience.