The Block-Oriented Network Simulator (BONeS) may be viewed as an integrated system that provides a complete graphical environment for the description and simulation of communications networks.There are many existing techniques for describing communications networks; including state transition diagrams, state transition tables, Petri networks, high level general purpose languages, and special purpose high level languages.Each of these techniques have their merits. However, none of these methods provide a an integrated, visual, hierarchical framework f o r the modeling and simulation of communications networks.The integrated environment of BONeS includes the capability to describe protocol functions, layers of the IS0 model, and network transmission effects in a heirarchical fashion using block diagrams; configure and execute a discrete event simulation of the network; perform design iterations; and analyze the system performance.Each of these capabilities is provided through a consistent user interface that relies on the extensive use of graphics, windows, and consistency checking to provide a visual environment for describing networks and their protocols.The environment makes extensive use of software engineering, workstation technology, and expert systems to provide an intelligent, user friendly and flexible tools for simulating communication networks.
INTRODUCTILN-Often simulation provides the only feasible method f o r analyzing the performance of communications networks.There are several software packages [Ref. 1-81 now in use that, to varying degrees, aid the system analyst in performing these simulation studies.However, none of these methods provides an integrated, visual, hierarchical framework f o r the modeling and simulation of communications networks.The Block-Oriented Network Simulator (BONeS) described in this paper does provide the advanced environment needed to describe and simulate communications networks. BONeS is a natural extension of the block oriented system simulator [Ref. 91 (BOSS).BONeS has many of the attributes of BOSS including: a block diagram approach to system specification (this is a unique approach for cnmnunication network), extensive error and consistency checking, and an integrated environment for the specification of the system, execution of the simulation model and the examination of the results. BONeS builds upon the BOSS structure.Features such as asynchronous execution of blocks and specification of data (message) structures are added.The purpose of this paper is to provide an overview of the BONeS network modeling philosophy and structure.
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BONeS NETWORK MODELING PHILOSWI?BONeS network descriptions are:
1.A visual display of all information, i.e., the user will not write in a simulation language as in [Ref. 1, 2, 3, 41, rather he will describe the system graphically as in [Ref. 5,6, and 81. BONeS provides, for the first time, a block diagram approach for describing communications network and their protocols in a unified manner. This approach is superior to other net...