In recent years, with the increase in Internet dependence, people are increasingly accessible to the network, sharing Internet resources, and services anytime, anywhere, anywhere, in a more flexible way. IETF provides a next-generation mobile IP (ie Mobile IPv6) on the basis of moving IPv4, and has great economic practicality, and can provide wireless connections for mobile computers. Supports any wireless media access, making mobile users on the network possible. The IETF proposed resource reservation agreement (RSVO) is originally a wired network design, providing a service quality (QoS) guarantee supported by resource reservation signaling, and is currently facing a lot of service quality requirements for mobile users. challenge. In the wireless network, since the user's frequent movement makes the end-to-end service quality assurance and the Handoff management more complicated.
First, related research
At present, there are many research on the service quality assurance of mobile networks and the switch management issues of mobile users, and some mobile IP architectures based on service quality are proposed. However, the architecture is based on mobile IPv4, resulting in "triangular routing" problem; some architectures cannot predict mobile behavior of mobile users, so that resource reserves cannot be implemented only within the necessary cells, but in all neighbor honeycombs Execution, resulting in waste of resources. Some experts have proposed Hierarchical Mobile Agents Tree [1, 2], which can solve the above problems and next-generation mobile IP architecture based on service quality and flat management ideas - mobile agent flat MAFS: Mobile Agents Flat Structure is an optimization of the hierarchical mobile agent tree architecture, regardless of how users are frequently moved, can provide reliable service quality assurance and efficient mobile switching management for mobile users regardless of how users are frequent.
Second, the basic concept of the mobile agent flat architecture
Service quality object option
The QoS Object Option is included in the Hop-By-Hop extension header that carries a bundled update information packet in mobile IPv6, which is shown in Table 1. This object can not only provide service quality assurance, but also serve as a resource reserved protocol, but also apply to the core network to achieve good service quality support.
In the service quality object option, the Service Quality Requirements domain describes the service quality requirements for mobile user data streams; the "maximum delay" domain and "time delay" domain describe the time delay that the mobile user data stream can accept. "Average Data Rate" domain, "Token Size" domain, "maximum data rate" domain, "minimum policy unit" domain, and "maximum packet length" domain describe the flow rate and its characteristics of the corresponding data stream The "Packet Classification Parameter" field provides a value of parameters that can be used for data packet classification in the packet header.
2. Mobile agent
The mobile agent acts as an entity that achieves reliable service quality guarantees by managing service quality object options and res reservations, and this is also completed with other and mobile related work. The mobile agent in the service-based mobile agent flat architecture proposed herein can be divided into two categories:
The first type of mobile agent is located at the bottom of the flat architecture. Its functionality is similar to the hometown agent in IPv6, through management service quality object option and resource reservation to meet the requirements of service quality, processing and mobile users related resource reservation protocols. Information, maintain mobile information related to mobile users, control mobile users within a certain range.
The second type of mobile agent is located at the top of the flat architecture, which can be seen as a merge node that is functional to meet the quality of service by managing service quality object options and resource reservations, and merges by resources when the mobile user is switched. Reserved Agreements Complete other and mobile related work along the path information and reserved information generated by the new routing. 3. Mobile agent flat architecture
From the perspective of management, with the expansion of the organization, the level of the organizational structure increases. The flat-type tissue structure is less than the vertical tissue structure, which reduces the intermediate management level, shortening the time of the instruction transmission, reducing the cost, increasing the elasticity of the organizational structure, enhancing the manager for organizational environment The rapid response capability of changes increases the utilization of resources.
The mobile agent flat architecture is an optimization of the hierarchical mobile agent tree architecture. It introduces the idea of flat management. It will optimize the mobile agent multi-stage vertical structure in the stratified mobile agent tree architecture to two flat flat structures, reduce The intermediate level of mobile proxy management, divides the mobile agent into two categories, reducing the time of signaling transmission, reducing the number of mobile agents, and solving the problem of service quality decline due to the frequent movement of mobile users Provide a reliable guarantee to meet the user's service quality requirements.
Third, the basic working principle of mobile agent flat architecture
In the mobile agent flat architecture, the mobile user's switching management and support policies based on service quality object options have the following cases.
1. When the mobile user is the sender of the communication, the corresponding communication node is the receiver.
When the mobile user is switched, the bundle update information with the service quality object option is sent along the mobile agent flat architecture to its communication node. The current mobile agent detects the service object option at the bottom of the moving agent flat architecture and immediately performs the resource reservation, sending a new path information to the communication node, the path information has the same source stream identifier before the switch before switching, while transmitting The bundle update information of the service quality object option is sent to the communication node. The new path information combines the mobile agent of the moving agent flat architecture, because the top moving agent has saved the data stream to create the path status created in the mobile agent flat architecture. This makes the resource reservation agreement only for mobile users only have a local modification. Thereafter, the top mobile agent transmits the reserved information associated with the mobile user's current location and the data stream, and the bundle update information of the service quality object option is forwarded to the communication node. Thus, resource reservation of this path from the top moving agent to the communication node can be reused. Then, after the communication node receives the bundled update information with the Quality Material Option option, the bundled confirmation information to the current location of the mobile user is transmitted through the mobile agent flat architecture. Thus, the data packet continues to transmit from a new location of the mobile user to the corresponding communication node. Figure 1 shows the schematic of this situation.
2. When the mobile user is the recipient of the communication, the corresponding communication node is the sender.
When the mobile user is switched, the bundle update information with the service quality object option is sent along the mobile agent flat architecture to its communication node. The current mobile agent detects the service object option at the bottom of the mobile agent flat architecture and immediately sends the bundle update information to the top mobile agent. Since the top moving agent has saved the data stream once created in the mobile agent flat architecture, immediately detect the service quality object option, and perform resource reservations, send new path information to mobile users, and also send The bundle update information of the service quality object option is sent to the communication node. After the mobile user receives a new path information, the reserved information associated with the data stream is sent immediately to the top moving agent. Thus, resource reservation of this path from the top moving agent to the communication node can be reused. This makes the resource reservation agreement a partial modification for mobile users. Then, after the communication node receives the bundled update information with the Quality Material Option option, the bundled confirmation information to the current location of the mobile user is transmitted through the mobile agent flat architecture. Thus, the data packet continues to be sent from the communication node to a new location of the mobile user. Figure 2 shows the schematic of this situation.
Fourth, the technical advantages of mobile agent flat architecture
With the full start of CNGI, my country's research on next-generation mobile IP network architecture and service quality has been fully launched. The mobile agent flat architecture can provide fast seamless switching and efficient service quality assurance in addition to the transparency of the truly two-way communication capabilities, the transparency of the network application, and the unrelated link of the link. In the mobile agent flat architecture, the round-trip path of the resource reserved protocol signaling is between the top moving agent of the mobile user and the mobile agent flat architecture, the round-trip path of the mobile IPv6 bundled update information and the bundle confirmation information is in mobile users and communication. The node is between, so the mobile agent flat architecture enables the resource reserved protocol signaling to become part of the round-trip path of the mobile IPv6 bundled update information and bundle confirmation information, so that the resource reservation protocol will be retrieved to communicate nodes. Updating a new user's new transfer address (CARE OF ADDRESS), especially when the movement agent flat architecture is more prominent when the link between the top moving agent of the mobile agent flat architecture to the communication node occurs. In other words, when the mobile user moves to a new subnet, the mobile user and its communication node continue to transmit and receive data, all data packets will be provided with the desired service quality assurance. And do not produce additional switching delays. In addition, the mobile agent flat architecture extends the traditional resource reservation protocol, increasing the service quality object option, and placed it in the HOP-BY-HOP extension of the bundled update information group in mobile IPv6, which can be quickly Seamless switching while meeting the service quality requirements of mobile users.
Five, junction
This paper proposes a new mobile agent flat architecture based on service quality. The architecture applies flat management ideas into a hierarchical mobile agent tree architecture and optimizes it, defines two flat flat mobile agent architecture, determines and enhances different functions of two types of mobile agents, and reduces intermediate management level. And the number of mobile agents, shorten the time of signaling transmission, providing practical, flexible, efficient, fast seamless switching capabilities and efficient seamless switching capabilities and efficient service quality assurance for CNGI mobile IP access network.
Although there are still many shortcomings in current mobile IP technology, mobile IPv6 programs have not yet been perfect, but with the implementation of CNGi, and the research on key technologies such as network architecture, service quality, and switch management, mobile IP. The perfect combination of communication technologies and IP technology refers to the day, people will eventually be achieved at any time, any location, and any kind of media to communicate with any person will eventually be achieved, and will also bring new market opportunities for telecom operators.
