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Currently, the architecture of software systems is shifting from “monolith” to “microservice” which is an important enabling technology of cloud native systems. Since the advantages of microservice in agility, efficiency, and scaling, it has become the most popular architecture in the industry. However, as the increase of microservice complexity and scale, it becomes challenging to monitor such a large number of microservices. Traditional monitoring techniques such as end-to-end tracing cannot well fit microservice environment, because they need code instrumentation with great effort. Moreover, they cannot explore the fine-grained internal states of microservice instances. To tackle this problem, we propose Kmon, which is an In-kernel transparent monitoring system for microservice systems with extended Berkeley Packet Filter (eBPF). Kmon can provide multiple kinds of run-time information of micrservices such as latency, topology, performance metrics with a low overhead.

In order to prove the performance of SCPS-TP which is proposed by CCSDS in researching space information network, this paper designs a SCPS-TP model including SNACK module, congestion control module and header compression module based on the three key techniques of SCPS-TP using OPNET. A space information network simulation platform is built, and the performance of SCPS-TP is simulated and compared to TCP. The simulation results show that SCPS-TP performs better in high Bit Error Rate and long round-trip delay environment than TCP.

In order to meet the security need of space network, the access authentication model was proposed. On the basis of that, the self-certified authentication protocol was designed according to “challenge-response” scheme. Moreover the security of the protocol was analyzed and the implement process was simulated. The simulation results shows, the access authentication time of space network user is mainly affected by the data processing time and communication link error rate. The research conclusion of this paper has important meaning to the space network security access authentication.

As the existing trust model is not suitable for the semi-distributed mobile P2P network, a dynamic trust model based on super node SDTM is presented. Trust relation is categorized into two kinds: ordinary node and ordinary node, super node and super node, and each solution for the two kinds is put forward. Meanwhile, SDTM solves the problem of the ordinary node dishonest feedback using direct trust tree of super-node. The simulation result shows, SDTM can effectively deal with the dishonest feedback of network attacks over the existing trust models, and legitimate nodes have a higher success request rate.

In the structured peer-to-peer (P2P) networks, distributed lookup protocol Chord can effectively solve the problem of resource location. However, because the routing table in Chord suffers serious information redundancy and the lookup direction of Chord is only clockwise, it is not very efficient. Therefore, a routing algorithm BNN-Chord (Bidirectional Neighbor's Neighbor Chord) based on NN-Chord (Neighbor's Neighbor Chord) is proposed in this paper. In order to improve lookup efficiency, BNN-Chord adds the coverage and finger density of routing table and repetitious entries are deleted, meanwhile, it introduces bidirectional routing mechanism. Simulation experiments show that our algorithm can remarkably reduce the average lookup path length compared with Chord and can improve system performance.

A mobile ad hoc network is an up-to-date one emerging with the development of wireless communication technology. Nowadays, it has become more and more popular. Along with the development, more and more authentication protocols in ad hoc network have been proposed. But the problem is that how to validate the security and efficiency of these proposed protocols. In this paper, we proposed a general model for modeling and simulation of the authentication protocols at application layer in mobile ad hoc network based on OPNET simulation environment to test performance of the authentication protocols. A prototype is implemented taking an authentication protocol based on self-certified public key as an example. According to the analyses of the simulation results, the authentication protocol satisfies the request of mobility factor of the MANET nodes and the effect to the end-to-end delay is limited. Quantitative references are provided for the study of authentication protocols for the mobile ad hoc network

This paper discusses the order-based deadlock prevention protocol with parallel requests (ODP3) [1]. From the analysis of theorems about ODP3, we found that the conclusions of paper [1] are not correct. The ODP3 method is not free from deadlock and live-lock. An example is given to illustrate our deduction.

The grid technology and distributed simulation functionality were firstly introduced. We proposed two approaches to integrate actual distributed simulation application into grid environment. The first one is to take advantage of grid technology to support distributed simulation, which is independent of the development of distributed simulation. The second one consists of using specific extensions of distributed simulation based on grid technology. We mainly focused on the latter and argued about integrating HLA technology into OGSA model in detail. Under the above discussion, we defined G-RTI concept, which means the Runtime Infrastructure (RTI) based on grid technology.

Aimed at coordinated resource sharing in distributed, heterogeneous dynamic environment, OGSA supports distributed simulation effectively in resource management. GT3 Core provides a structure of service container, based on which a new mode of distributed simulation system has been designed. The new mode realized the separation of simulation resource and simulation applications, and supplied a simulation server responsible for the organization of simulation resource. The server provides service index for higher simulation applications and enable the interaction among them. Under this new simulation mode, a combat simulation application has been developed as a prototype. It achieved well reusability, portability of simulation resource, and supported heterogeneous, cross-platform application development.