Basic Mobile IPv6 technology

We all said that Vista has played a significant role in IPv6 networks, but the development of mobile communication has also played an important role in IPv6. Now let's talk about the mobile IPv6 technology. Let's take a look at the working principles of Mobile IPv6 technology.

1. Introduction to Mobile IPv6 technology

The current Internet protocol is an IPv4 version. As the new version of the IP protocol, IPv6 inherits many features of IPv4, and its huge address space will be able to meet the rapid development of the Internet, it also integrates mobility, security, and service quality. IPv4 does not provide any mobility support. In response to this situation, IETF began to develop a protocol to support mobile internet devices in 1996. The Mobile IP protocol has two versions: IPv4-based mobile IPv4 and IPv6-based mobile IPv6.

IPv6 is the next generation Internet protocol, which will eventually replace IPv4 as the main network protocol of the Internet. Mobile IPv6 is built on the IPv6 architecture and is an integral part of the IPv6 protocol. It has become one of the essential functions of IPv6. Compared with other routing protocols, Mobile IP has special features. Mobile IPv6 uses some new features of IPv6 to support mobile IP addresses. Mobile IPv6 allows the network nodes equipped with the IPv6 protocol stack to move between different IPv6 CIDR blocks, you can use a fixed IPv6 address. Because the IP address does not need to be changed during the process of moving, IPv6 nodes can maintain the original Transmission Control Protocol (TCP) or Datagram Protocol (UDP) when moving between different network segments) communication is not interrupted. Mobile IPv6 is completely transparent to the transport layer and the application layer protocol, that is, whether the network node moves or not is not transmitted to the transport layer and the application layer. All features supported by mobility are provided by the IP layer. Compared with mobile IPv4, mobile IPv6 significantly improves its performance and simplifies the work process so that mobile nodes can connect to any link with a permanent IP address. At the same time, IPv6 no longer requires the necessary foreign proxy routers in the mobile IPv4 to work together because of the IPv6 automatic Address Configuration mechanism, mobile IPv6 also solves problems such as triangular routing and entry filtering in IPv4.

2. Working Principles of Mobile IPv6

The following is a simple example to introduce the IPv6 solution to mobile problems. When mobile node A is linked to the home link of link 1), it has an address A1, which can be reached through the home proxy. When mobile node A does not move, when communication between Communication Node B and mobile node A, the data packet sent by Communication Node B will arrive at mobile node A according to the existing routing method.

If mobile node A does not change its IP address, the data packets sent by communication B cannot reach the mobile node A according to the existing routing method.

1) vro2 2 Periodically broadcasts the RouterAdvertisement message with the prefix information on the local link. After receiving the message, mobile node A knows that it has moved, it will automatically configure a new address A2 based on the new prefix information. We call it the forwarding address care-ofaddress );

2) mobile node A will send an information package M2 to the home site proxy. This information package tells the home site proxy that the new address A2 of mobile node A is now available. After that, the home site proxy then finds the original A1 data packet that needs to be sent to mobile node A. It will intercept this data packet and then use this package as the net load, add an IPv6 Header on it to send new data packets to the new address A2 of mobile node A. This process applies the "tunneling technology ";

3) If Communication Node B sends data packets to mobile node A, it does not know that mobile node A has moved, at this time, it will send this packet to the original address A1 of mobile node;

4) after the data packet sent by Communication Node B arrives at the home site proxy, the home site proxy intercepts the data packet and forwards the data packet to the new address A2 of mobile node;

5) After receiving the data packet forwarded by the home site proxy, mobile node A checks the source address of the data packet and knows that Communication Node B wants to communicate with it, therefore, it will send an information package M3 to Communication Node B and tell its new address A2;

6) After receiving the data packet, Communication Node B records the new address A2 of mobile node A. If another data packet needs to be sent to mobile node A, it directly sends the data packet to address A2. Now, two-way communication can be implemented between mobile node A and Communication Node B;

7) if other nodes want to communicate with mobile node A, the process of establishing communication between mobile IPv6 and Mobile Node B is similar.