| With the maturity of 5G technology and the development of mobile network,content sharing services in the mobile environment have become the mainstream of Internet services,it has occupied 85% of Internet visits in2019.On the other hand,the existing TCP / UDP / IP Internet is developed based on the wired network architecture,so the information explosion caused by the mismatch between the content sharing model and the mobile network architecture,and the end-to-end static connection cannot adapt to the dynamic topology of the mobile network Contradictions such as the inability to decouple content / addresses caused by capabilities have become increasingly prominent.In view of the above contradictions,this paper focuses on the two key issues of content sharing efficiency and node trust selection in distributed scenarios,focusing on cross-layer optimization design methods,analyzing and studying the performance of mobile /dynamic conditions on content sharing and node trust influences.This paper firstly sorts out the system model of the distributed trusted network,gives a Markov chain model based on node migration characteristics for mobile conditions,and stratifies the distributed content sharing process under mobile conditions.The Markov chain model shows that the current distributed content sharing mechanism under wired network conditions usually adopts the peer to peer mechanism.Its distributed hash table,tree,mesh and other structures are the key to the construction of future integration of distributed computing,blockchain and Bitcoin.However,when it is carried by the mobile network below the transport layer,there will still be difficulties such as limited underlying resources and credible mobile migration.It is necessary to further optimize on the basis of the traditional distributed network architecture.The paper focuses on the scope of the underlying resources and common allocation methods,as well as the basic model of content sharing and credibility.For the resource allocation methods of the mobile network,the existing economic principles and Lagrange dual decomposition are pointed out.The model definition of peer node selection and credibility management in the migration scenario has laid a foundation for the discussion of subsequent research.This paper aims at the coupling process of distributed network and underlying mobile attributes,and presents an optimized solution for joint control of the underlying bandwidth and power across layers under the condition of limited content sharing resources.The paper first considers the traffic expansion,mobile dynamics,and routing energy efficiency exposed by the traditional interconnected architecture due to the underlying mobile attributes,and defines the weighted average energy efficiency index as the optimization goal of system performance improvement.On this basis,we focus on the coupling between physical layer control optimization and content sharing efficiency under mobile network conditions.Based on the content sharing efficiency index,we study how to reasonably allocate communication link bandwidth to improve the network under the constraints of ensuring network capacity,and reduce energy consumption through the control node transmit power at the same time.Under the mobile condition,the content sharing process not only needs to consider the content sharing model,but also considers the mobile node’s active ability,mobile node’s processing ability and other factors,so even under the relatively static network topology,cross-layer coupling between links will cause the optimization problem of system content efficiency transformed into a nonconvex model.The paper revolves around the numerical solution method of the corresponding non-convex model,by constructing continuous successive convex approximation(SCA)method to deal with the complex non-convex problem,and realizes the convergent approximate solution of the original function based on the approximate equivalent method,namely sub-optimal solution.The numerical simulation results show that the JPBCA algorithm proposed in this paper forms a different idea from the existing DSPC,EEBA and other methods,can effectively perform the optimal solution approximation of non-convex functions,and can effectively solve the resource allocation problem of distributed networks in mobile environments.This paper aims at the node’s trust selection strategy in application layer,and proposes an optimized scheme of trusted node selection strategy based on the concept of cross-layer optimization,which solves the problem of how to select trusted content nodes in the mobile environment.From the perspective of content distribution producers,when the traditional peer to peer protocol is used in a mobile environment,content producers may cause another type of content sharing inefficiency due to the inability to guarantee link reach ability.The paper sorts out the optimization objectives from two perspectives of distance measurement parameters and trust index,and establishes a data transmission system model for content generation and distribution in a distributed network under mobile environment,and gives two performance evaluation optimization indexes: transmission success rate and average download time.On this basis,the paper extends the traditional wireless Mesh network hybrid routing protocol,introduces Airtime Link Metric as the underlying metrics of the communication network,and restricts the content distribution behavior of nodes based on the node trust index.Specifically,based on the transmission success rate and average download time parameters,the data transmission probability function of node selection strategy is modified,and the underlying indicators are introduced into the content distribution process.A new trusted node selection strategy for mobile environments is proposed based on the routing default Indicators to ensure that there is no additional protocol overhead and compatibility.At the same time,the number of nodes that can complete the content download is increased within the overall content distribution range of the cluster.The simulation results show that the trusted node selection strategy proposed in this paper can adapt to the highly dynamic changes of the nodes,and can effectively improve the content sharing efficiency of the distributed network in the mobile environment while ensuring the credibility of the content.At the end of the paper,the technical background of the introduction of peer to peer content sharing in the mobile environment is comprehensively summarized,the research focus and innovation points of this paper are summarized,and the research focus of the future peer to peer technology architecture,protocol and network security in the mobile environment is pointed out. |
