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Most of the time-sensitive networking standards are based on a high precise and reliability time reference, which is accomplished by IEEE 802.1 AS. However, the accuracy and reliability of clock synchronization could be affected in practice. To conquer the inaccuracy resulting from the collision between different packets, an algorithm that combines time-slot-based synchronization and priority scheduling is proposed. To improve the reliability, an abnormal recovery strategy of the master clock is proposed. The proposed algorithms are implemented on the OMNet++ simulation platform with an typical in-vehicle network topology. The simulation results show that the clock synchronization accuracy could achieve sub-microsecond level even if there are interference flows, and the abnormal recovery mechanism can maintain the stable state of the clock.

Regenerating codes (RGCs) have recently been proposed to reduce the repair traffic of ( $n,k$ ) erasure-coded distributed storage systems. Moreover, RGCs can also be used in a scalable distributed storage scenario where $n$ is increased (decreased) to upgrade (degrade) redundancy while maintaining the maximum distance separable property of erasure codes. In this paper, we propose a new application of minimum storage regenerating (MSR) codes in storage scalability. The connection between repairing invalid nodes and adding new nodes suggests that the two processes can be unified in the same framework. We consider both single and multiple node situations, and two methods for constructing multiple nodes are proposed: concurrent and sequential. We focus on proving the achieved capability of concurrent MSR that can consume minimum traffic for generating multiple nodes. Because concurrent MSR is sensitive to both the number of helpers and added nodes, sequential methods make scalable MSR generalizable. The examples show that the scalable MSR codes have the same advantage of saving network traffic as repairing failures.