IPv4: addresses represented by 32-bit binary data, grouped into four sets of eight digits, then expressed in decimal. As is well known, today’s internet protocol is IPv4, now 26 years old. When it was created, IPv4 was more than enough to connect the few thousand computers of that era, and its inventor believed that 4.3 billion IP addresses would be enough to meet humanity’s needs forever. But 30 years later, in today’s world of computing devices, 4.3 billion is no longer enough — and the reason is that within that theoretical 4.3 billion, far too many IPs sit idle. Many campuses hold huge numbers of IP addresses but only make them available to people within the school, which creates enormous waste. At the same time, many places are facing IP exhaustion — Germany’s IP supply will only last another 4.5 years, and once the last IP is used, new users will have to access the network by sharing addresses, with multiple users unable to get online simultaneously — imagine the inconvenience that would cause! IPv6 was born out of exactly this situation. IPv6 represents addresses with 128-bit binary data, grouped into eight sets of sixteen digits, then expressed in decimal. Its notation is far more cumbersome than today’s IP addresses. But it can allocate 667×10^15 addresses — with this system in place, we can assume that even a thousand years from now, humanity still won’t be able to exhaust it.

In terms of usage, IPv6 offers higher security and optimization for VoIP. The security features it introduces include payload length, next header, and hop limit. IPv6’s advantages for mobile use are also self-evident — every mobile device can have its own unique IP, so it can use the same IP to get online no matter where it is. At the same time, operating systems have already prepared to welcome IPv6’s arrival. Support for IPv6 was provided as early as Windows XP SP1. If XP was the foundation, then Vista is the towering building on top of it, because Vista offers full support for IPv6 and can automatically switch between IPv4 and IPv6, making this transition far more convenient. And it’s not just Microsoft — Mac and Linux have also prepared for IPv6. However, because server manufacturers aren’t yet ready, we won’t be able to use IPv6 for the next few years. But there’s no doubt that IPv6 has raised the curtain on the internet of the new century — in the future, the internet is bound to become even more tightly woven into human life.