This article is just a note I learned IPv6, the content is not a formal technical discussion, if there is an error, don't be strange
One: What is IPv6? Is an upgrade version of IPv4, IPv4 everyone can be familiar, in contact every day. A Version 4, now upgraded to Version 6. Everyone knows that the upgrade of the software version means more features, better interfaces, then the upgrade of IP is also the same. Ability to get more address space, better security, better transmission performance.
Two: Why do IPv6? We grow, the network is growing. Previously, the developed countries in Europe and America had the Internet. Now those of the third world, people also like the Internet. Everyone is rushing to the Internet, so the original IP address allocation has problems. Although some IP addresses in the United States hold a lot of IP address in the hands of the big man, it is like a person who holds money in his hand, it is refused to make money easily. The larger in these IP addresses is in the 1980s, although they may have only a small number of hosts, but because they all have no one and they grab the IP address, they are all divided into a lot of Class Class B address. And some big companies have also received the IP address of the acquired company by acquiring other companies. Such as Digital, was acquired by Compaq, while Compaq was acquired by HP. It is to know that Digital and Compaq have each a large piece of Class A address.
When the IP address on the network is getting less, and there is a serious hindering advancement of our technology (such as wireless network, mobile network development, they all need IP address), we have to study new IP address assignments. Program. IPv6 is based on the product born in this state.
Three: IPv6 history In fact, IPv6 has a long history, at least than your imagination. The IETF organization began IPv6 construction in 1990. And IPv4 is expected to be assigned in 1994 in 1994. But now it has arrived in 2004, why are we still using IPv4? The reason is very simple, because the appearance of a large number of "patch" technologies can extend the use time of IPv4. For example, NAT technology, CIDR technology, etc. At the beginning, there were three programs in the future instead of IPv4, 1: Internet common structure (RFC 1707); 2: Enhanced Simple Internet Protocol (RFC 1752); 3: Recommended with CLNP instead of IP (Layer 3) (RFC 1347). When the smoke is exhausted, the final SIPP (Enhanced Simple Internet Agreement) occupies the upper wind. Its address length is 128 bits, the main author is Steve Deering. IPv6 is called IPNG, and the first specification is RFC 1883. It is only renamed IPv6 in 2001. Cisco iOS has provided support for IPv6 at 12.2 (2) T. WINDOWS XP also supports IPv6. Whether China's Huawei supports IPv6, I don't know.
Four: The advantage of IPv6 1: 128 Bit address program allows us to use IP addresses to have endless age. 2: It can also improve the world's unique address, such as PDA, cellular and 802.11 system, etc. for hundreds of millions of new equipment. 3: IPv6 has a multi-level hierarchy, which can help routing aggregation and improve efficiency. 4: ARP broadcasts are replaced by multicast. As we all know, ARP is a very "stupid" broadcast approach. It is possible to bring "storm." 5: The new tag field can provide traffic distinguishing. There are other benefits such as safe, movable benefits, but these benefits IPv4 are also available, which is not detailed here. There are a lot of benefits, and now it is nowhere to do not need. Five: IPv6 is inadequate (said shortcomings too much) 1: The address that is difficult to remember, the address of memory IPv4 has made us feel uncomfortable (so there is DNS), not to say IPv6 8 16-bit hexadecimal fields IP address. Such as 2001: 0410: 0000: 1234: FB00: 1400: 5000: 45ff This is an IPv6 address. Although IPv6 provides an abbreviation, there is still a problem that is difficult to remember. 2: It is temporarily unable to fully replace IPv4. I don't know when I replaced it. Because in accordance with the current trend, it will be far from now. 3: Since it is not possible to fully replace, it is necessary to coexist with IPv4. There are also some technical problems in coexisting, although it is not difficult to solve, but there is always a problem, solve the need to human and financial resources.
Six: A small knowledge has IPv4, IPv6, then you may ask if there is no IPv5? Asked! Your idea is very open. IPv5 is also known as ST2 (Internet Flow Protocol Version 2), is an experimental resource reserved protocol, mainly in distributed multimedia (such as voice, video, and real-time data traffic). IPv5 is the same as the frame of the link layer and IPv4, you can refer to the two documents of RFC 1819 and 1190 get more information.
Seven: A little joke then raised the IPv9 in China? Time has proven that this is a joke. If you still don't understand why, I suggest that Google will find it. But don't laugh, the foreigner has already opened this joke in 1994, you can check the RFC 1606 (title is a histical personpective on the usage of ip version 9), carefully read you will find a very wonderful place . The document release date is April 1! Oh, the humor feeling of foreigners is really strong.
