Study And Accomplishment Of Network Load Balance Based On The Application Delivery Networks Technology

Application Delivery Networks Technology is a comprehensive platform, which specialize in the bottleneck problems of user's key application network visit through load balances of service device, chains, overallandWan'soptimizing Accelerationand web's Accelerating and many other technologies. With the development of China'selectronic government affairs, the government office network has a tendency towards every staff.Thenetwork is becoming larger and larger which involing in growing departmentsandareas;leading to more and more loading of the application and the datas.Meanwhile, the demands of the government's employees are more higher and more diversified.These days,the net work basic chains are better,while there are more and less problems of slowliness of key application visit when it is used in the network, which cause a lot of troubles. Under this circumstances, which is required to apply new technologies, creating new ideas, perfecting and reorganizing the network resources, improving the network management level in orderto promote data's effective and usage and make theeletrical governmeng affairs more safe, effective, quick and orderly operating, which is required to introduce Application Delivery Networks Technologies.The government office network is coming to every offical. The network is becoming larger and larger which involing in growing departments and areas; leading to more and more loading of the application and the datas. Meanwhile, the demands of the government's employees are much higher and more diversified. These days, the network basic chains are better, However, many questions appears, such as the key application visit speed goes slowly, which cause a lot of troubles. Under this circumstances, to application of new technology is required, creating new ideas, perfecting and reorganizing the network resources, improving the network management level in order to promote data's effective and usage and make the eletrica governmeng affairs more safe, effective, quick and orderly, which require to introduce application delivery networks technology.The application delivery network technology connects the key application with the foundation network equipment. This seamless union of the platform and Microsoft, IBM, Oracle, SAP, BEA, People Soft and many other company's products realize the security, fast and high available delivery in their application in the network. This enables it to become the important control point in the network and it can increase the intelligence and the administration, unloading appliacation in order to lighten the server burden and avoide rewriting the application. Thus, the application delivery network technology which is similar to a network city manager guarantee the application fast, high available in any network all the time.Several aspects of the questions has been discovered through thorough analysis of the project background network. First, how to promote fully the line by using the backup line emergency response ability and the band width; Secondly, how to provide the application service by using the old equipment resources and using the server cluster; Thirdly, how to guarantee the quality of the key application service in the band width resources in limited situation; Finally, how to guarantee the security of network in the complex network application environment. Transformational Network topology is proposed in view of the existing problems, by using four application delivery network controller 6400 of F5 Corporation to realize link load balance, server load balance, firewall load balance and the functions of inside and outside net DOS attack protection.The design realization of double link load balance of China Net and China telecommunication, it aims at the demand of internal user load balance (the Outbound visit) and (the Inbound visit) the current capacity intelligence link chooses two aspects to Internet visit from Internet visit to network interior server, fully promotes the line using the backup line emergency response ability and the band width, guarantee normal visit of the Internet user when some link line is broken and can defer to the appropriate load equalization algorithm to choose a link of superior quality when two links are normal; while exterior user can act according to the link the automatic system checkout program result and the corresponding algorithm (Topology, RTT and so on) when establish domain name request connection, the intelligent chooses appropriate link to provide the response of the user.Design realization of the server load balance use the idle server fully, enhance the whole service level, guarantee the quality of key application service in the band width resources within the limited situation, automatically inspecting server active status, dynamically increasing or deleting any quantity server of its load balance server group and do not need to make any change to the client side or the backstage in order to cause the system expansion to be relaxed. When any service engine is off, instantly the current capacity requested assignment for other servers, thus achieves the system high available.When the current capacity"the peak value"appears, it can mix all servers the resources simultaneously in order to provide the service. So-called"peak value jamming"pressure is weaken obviously when the system performance is enhanced greatly, simultaneously reducing the investment which increase for the regulating system performance.With the firewall load balance design's realization, the two different brand of user's firewall can work together and share the pressure together. The load balance product is from top to bottom, the sandwich structure of firewall is in the middle which realize the firewall load balance, two firewalls can carry out their processing performance 100% without making HA, and has made some promotion preparations for future isomerism firewall system (different brand firewall, or different model firewall) the development and sharpen the firewall colony's handling ability.The design's realization of inside and outside net DOS attack and protection through surveying the server handling ability precisely, thus automaticly shield newly built link before the server handling ability is saturated. The link which surpass the server handling capacity is at the waiting condition on the load balance products until the servers have free time or TCP timeout. At the same time, regarding all foreign provides the application the server, the user is unable to get in touch with the server, and it has to link with the hypothesizing server which is established on the load balance product , therefore the hacker is unable to obtain the server the real address. and increase the difficulty of the hacker attack. The security has gotten further promotion in the increasing complex network application environment.With the application of more complicated system of every units', there are more and more users. The Application Delivery Networks Technogies will have chance to guard the system's high-speed, safe and avaiable. In a word, our times need the Application Delivery Networks and the users are hoping Application Delivery.