Biblio

The operating system is extremely important for both "Made in China 2025" and ubiquitous electric power Internet of Things. By investigating of five key requirements for ubiquitous electric power Internet of Things at the OS level (performance, ecosystem, information security, functional security, developer framework), this paper introduces the intelligent NARI microkernel Operating System and its innovative schemes. It is implemented with microkernel architecture based on the trusted computing. Some technologies such as process based fine-grained real-time scheduling algorithm, sigma0 efficient message channel and service process binding in multicore are applied to improve system performance. For better ecological expansion, POSIX standard API is compatible, Linux container, embedded virtualization and intelligent interconnection technology are supported. Native process sandbox and mimicry defense are considered for security mechanism design. Multi-level exception handling and multidimensional partition isolation are adopted to provide High Reliability. Theorem-assisted proof tools based on Isabelle/HOL is used to verify the design and implementation of NARI microkernel OS. Developer framework including tools, kit and specification is discussed when developing both system software and user software on this IoT OS.

Realistic and scalable testing systems are critical to evaluate network applications and protocols to ensure successful real system deployments. Container-based network emula- tion is attractive because of the combination of many desired features of network simulators and physical testbeds . The success of Mininet, a popular software- defined networking (SDN) emulation testbed, demonstrates the value of such approach that we can execute unmodified binary code on a large- scale emulated network with lightweight OS-level vir- tualization techniques. However, an ordinary network em- ulator uses the system clock across all the containers even if a container is not being scheduled to run. This leads to the issue of temporal fidelity, especially with high workloads. Virtual time sheds the light on the issue of preserving tem- poral fidelity for large-scale emulation. The key insight is to trade time with system resources via precisely scaling the time of interactions between containers and physical devices by a factor of n, hence, making an emulated network ap- pear to be n times faster from the viewpoints of applications in the container. In this paper, we develop a lightweight Linux-container-based virtual time system and integrate the system to Mininet for fidelity and scalability enhancement. We also design an adaptive time dilation scheduling mod- ule for balancing speed and accuracy. Experimental results demonstrate that (1) with virtual time, Mininet is able to accurately emulate a network n times larger in scale, where n is the scaling factor, with the system behaviors closely match data obtained from a physical testbed; and (2) with the adaptive time dilation scheduling, we reduce the running time by 46% with little accuracy loss. Finally, we present a case study using the virtual-time-enabled Mininet to evalu- ate the limitations of equal-cost multi-path (ECMP) routing in a data center network.