P2P Technology In Large-scale Network Surveillance Management Platform Application

Along with the economical development and enhancement of the people's safety realization, the application of large-scale monitoring network platform already became the main development direction of network monitor profession, in other words how to construct a reliable network environment, the guarantee document and the video signal stable transmission, already became the most important problem to be solved of monitoring profession. The P2P technology should enter people's field of vision according to its characteristic and advantage.P2P directly contacts with the people, lets the people communicate with each other by the Internet directly. P2P causes communication easier in the network, more direct sharing, truly to eliminate the middle business. P2P is the person may directly link the computer and document of other users, but was not connects the server to glance over and downloading like the past. The important characteristic of P2P is changes the Internet present condition take the big website as the central condition, returns to "the non- center", and returns the authority to the user. Although does not completely achieve the non- center, but the convenient network correspondence, direct information sharing, computer user's file transfer and so on, these characteristics were the powerful technical guarantee of P2P technology.Certainly if want to set up a network environment of P2P,the most important premise is to solves the analysis problem of IP address, has developed the server end and customer end procedure for this. Using the translation technology of network address, the network address translation is produces in the IP address deficient situation day by day; its main goal is using the address repeatedly. NAT divides into two big kinds, basic NAT and NAPT (Network Address/Port Translator). NAT is a function module which moves on a router. First proposes is basic NAT, its production based on following fact: A center pitch point of private network (territory) only has the very few pitch points to need to connect with the outside net. Then in this stature network actually only minority pitch point needs the global only IP address, other pitch points IP addresses should be used repeatedly. Therefore, the function of basic NAT is very simple, uses the IP sub-webpage in the sub- net which retains, these IP is not obviously outside. In the sub- net only the minority IP address could connect the genuine global only IP address. If the points need to visit exterior network, then NAT is responsible in transform sub- network IP of this point to global only IP then transmits. (NAT can change the original IP address in IP package, but cannot change a port of IP package). Moreover one kind of NAT is called NAPT, we also maybe able to see from the name, NAPT not only can change IP address which passes through this NAT equipment, but also can change the TCP/UDP port of IP data. This basic network skeleton already been completed .In the system design has mainly expounded whole idea of this software, as well as database design. Divide thissoftware according to the function: Database operation class, network joint character class, service end and customer end etc. several modules. The database operation class has defined the function and method of related database operation, carries on read-write to the database in the service end procedure. The network joint character class has defined the function and method which uses in some network correspondences, for instance network initialization and receive, transmission information and so on, transferred when communication on customer end and server end, it is the main body of entire procedure information, document and video frequency transmission. The server end procedure mainly installs on the server's host computer to be the crucial point of connection entire network, simultaneously also is the bridge between customer end and database information. The computer which installed this procedure could join to the P2P network environment, this procedure also provide the guarantee of distribution and extension for the entire network. These functions module was constituting an organic network main body together, mutually coordinates works, had the essentially enhancement compare with the former monitoring network no matter in the security, stability, vigorous and healthy, extension and so on.In detailed design concrete introduce realization flow and key code of each module and sub- module. Through analysis of entire software demand and concrete realization situation of each function, makes this design accurately, succinct, reasonable as far as possible. It is easier to complete each link and realize each function under the instruction, andbecause the system design reasonable analysis already has defined the connection in these independent modules which connects with other module even entire network environment, like build a building: Had the good design paper, but also takes a brick to build, in the detailed design elaborates this kind of rampart brick process.The application of P2P technology in the large-scale monitoring network platform, enhance the function of entire platform, this also the goal of compiles this software, in present, this set of system basically has already realized the above all functions and through the test, could put into the use immediately. But as a result of company's project progress, demand of customer aspect and so on, original direction not be going on research. For instance says from the technology, use handling ability of customer end, realize point to point communication between customer end and service end, realizes irrelevant of communication service end (or customer end is serves end). But, speaking of the existing agreement, separated from the service end completely is also not realistic, therefore although theoretically the majority of communications do not need to pass through the service end, in fact in the operation also has involved the service end formidable and visits the handling ability, this point is created by the insufficiency of present point to point communication. It is impossible to discuss p2p temporarily if deviate from the center service. If the solve this question, the performance and efficiency of entire P2P network will be able to obtain an essence promotion. In brief any technical development all needs theprocess of explores, I believed that the P2P technology can be brighter in the large-scale monitoring network management platform.