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An approach to verification and validation of a reliable multicasting protocolThis paper describes the process of implementing a complex communications protocol that provides reliable delivery of data in multicast-capable, packet-switching telecommunication networks. The protocol, called the Reliable Multicasting Protocol (RMP), was developed incrementally using a combination of formal and informal techniques in an attempt to ensure the correctness of its implementation. Our development process involved three concurrent activities: (1) the initial construction and incremental enhancement of a formal state model of the protocol machine; (2) the initial coding and incremental enhancement of the implementation; and (3) model-based testing of iterative implementations of the protocol. These activities were carried out by two separate teams: a design team and a V&V team. The design team built the first version of RMP with limited functionality to handle only nominal requirements of data delivery. In a series of iterative steps, the design team added new functionality to the implementation while the V&V team kept the state model in fidelity with the implementation. This was done by generating test cases based on suspected errant or off-nominal behaviors predicted by the current model. If the execution of a test was different between the model and implementation, then the differences helped identify inconsistencies between the model and implementation. The dialogue between both teams drove the co-evolution of the model and implementation. Testing served as the vehicle for keeping the model and implementation in fidelity with each other. This paper describes (1) our experiences in developing our process model; and (2) three example problems found during the development of RMP.
Document ID
19960011352
Document Type
Contractor Report (CR)
Authors
Callahan, John R. (West Virginia Univ. Fairmont, WV, United States)
Montgomery, Todd L. (West Virginia Univ. Fairmont, WV, United States)
Date Acquired
September 6, 2013
Publication Date
January 1, 1995
Subject Category
COMPUTER PROGRAMMING AND SOFTWARE
Report/Patent Number
NASA-CR-200026
NIPS-96-07270
NAS 1.26:200026
Funding Number(s)
CONTRACT_GRANT: NCCW-40
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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NameType 19960011352.pdf STI