Machine-Assisted Parameter Synthesis of the Biphase Mark Protocol Using Event Order Abstraction

Abstract

We present machine-assisted timing-parameter synthesis of the biphase mark protocol (BMP) [1] using event order abstraction (EOA)[2]. By using EOA, we separate the task of synthesizing parameter constraints that guarantee key safety properties of BMP into two parts: 1. Safety property verification of the protocol by a conventional untimed model-checker under the condition that “bad” event orders do not occur; and 2. Derivation of timing parameter constraints that are sufficient to exclude bad event orders in the protocol, using our tool MeTEOrS. Though the user has to provide information about bad event orders, the rest of the synthesis process is automated. With the case study presented in this paper, we provide the community with two new pieces of information about BMP. First, the synthesis process using EOA produces, as a by-product, a list of all “bad scenarios” of BMP that would happen when parameters are tuned incorrectly. Second, the MeTEOrS tool provides information about which parameter constraint in the finally derived conjunction of constraints is actually sufficient to exclude each of these bad scenarios.