IPv4 address pool was 2011.02.03 distribution, but this seems to have no impact on our lives, 11 years later, at least in our country increases the hundreds of millions of mobile phone, also not heard of where on the network, chat don't day, 15 years AppStore also formally with the requirements of IPv6, but this in addition to the App developers to torture a phone, also don't seem to affect,
Is, in fact, we through complex but for individual non-inductive technology erased address shortage impact on us, such as zhang SAN to li si sent WeChat messages, so zhang SAN information to tencent server first, and then by the server forwarded to li si's mobile phone, why zhang SAN can not directly send bill? That's because li si no public IP, li si and the company dozens of colleagues sharing an IP number, if we send express, can sign li si, so although Shared an office, Courier or ability to li si, li si this time actually is formed part of the delivery address, but bill can't become a part of the IP address, so why tencent server can send bill? Because li si WeChat client (the client all people are all the same) periodically (every minute) to tencent server to send a special message, commonly known as "heartbeat packets", maintain the long connection of information, so with the help of zhang SAN to tencent's long connection, and then by tencent and li si long connection, so zhang SAN messages can be sent to li si, li si back to zhang SAN is the same way,
So why zhang SAN can and tencent server to maintain a long connection? Zhang SAN is in the company, there is "NAT" with the IPv4 IP sharing technology, the full name of "Network Address Translation", is a Network Address Translation, essentially, zhang SAN's company has only one IP Address, but through NAT, and increased the port Address 2 bytes, as part of the Address, such as zhang company IP is 202.105.39.75, through NAT, give zhang SAN WeChat with an independent channel 202.105.39.75:1456, by 1456, the information can be accurate to zhang SAN, but then again, why can't bill through 202.105.39.75: send a message directly to the 1456, the problem here is that 1456 is created by temporary for tencent server communicate with zhang SAN, intelligent they both use this time, the next ten minutes this Address may not, in order to maintain the 202.105.39.75:1456 addresses are available, then the two sides has maintained this session, there is no real news, then send a heartbeat packets to maintain this connection,
But it is not a wanted to build the connection created can be built, such as tencent server and zhang SAN, so will address common problems and cannot find zhang SAN directly, but zhang SAN can find tencent, because tencent server address is the exclusive server, there is no problem of sharing, so zhang must be as the sponsor of the connection to create this connection,
But not in the field of embedded with the industry, so good service, dozens of K RAM completely can't run on the Android to, can't install WeChat, then it can only be done through own server transfer, because almost every such devices have similar needs, so all kinds of "cloud" began to emerge in endlessly, provides the data transfer of cloud, the cloud can store data, but the cloud both in public clouds and private clouds to pay costs,
Cloud also has a lot of problems, a myriad of devices to share the bandwidth, Shared storage, security and speed is a problem, the user wants to free operating data is a problem,
So what are the good way?
The answer is IPv6!
IPv6 is geared to the needs of the next generation of Internet protocol, it put forward at first because use 32-bit address length IPv4, only about 4.3 billion address, in order to expand the address space, the proposed by IPv6 to redefine the address space, IPv6 USES 128 - bit address length, almost can not restricted to provide address,
IPv4 has 4294967296 addresses (232),
IPv6 (2128) 340282366920938463463374607431768211456 addresses (3.4 trillion quintillion addresses), equivalent to the surface of the earth can be allocated to 67 trillion addresses per square meter as the main body of consumption "personal" has no independent IP addresses are available,
Unlimited extension ability: (IPv4 address space x 4.3 billion x 4.3 billion x 4.3 billion, 4.3 billion) is enough to make every grain of sand on the earth has an address

So our PC, router transmission, the sensor in the factory, or remote control motor, electric light can have a unique address, so zhang SAN again to give Li Sifa news is no longer by tencent,
If IPv6 is used in industry, that is to say our DTU, RTU can direct, through their routing, our PC can also be hung with tiny devices under direct!