Executable Graphics for PBNM

Policy-Based Network Management (PBNM) is the application of specific, organisation-level rules in the context of networking, in particular for network management operations. The specification of a policy is performed in a policy language, usually following a textual representation. However, humans process images faster than text and they are prepared to process information presented in two or more dimensions: sometimes it is easier to explain things using figures and their graphical relations than writing textual representations. This paper describes a visual language, in the form of graphics that are executed in a networking environment, to define a network management policy. This approach allows to map visual tokens and corresponding arrangements into other languages to which a mapping is defined

A system for rapid prototyping of visual language environments

The paper describes a visual environment generator, the VLPEG system. based on the Symbol Relation Grammar model. The system exploits a classifcation of visual languages in terms of graphical symbols and the relatiomhips among fhem. For each class a lexical analyzer is able to interpret fhe physical layout of any drawn visual sentence and to provide a corresponding high level representation. Thans to this capobility the visual language designer may disregard the physical features and specify the language ai a high abstraction level. VLPEG supports the rapid prolotyping of visual environments and afers the designer the possibiliry to operate in automatic generation made, by explaifing a grammar inference module. This capability allows the designer to focus on the structural features ofthe target language and quickly receivefeedbackfrom the customer during fhe language prolotyping process.The paper describes a visual environment generator, the VLPEG system, based on the Symbol Relation Grammar model. The system exploits a classification of visual languages in terms of graphical symbols and the relationships among them. For each class a lexical analyzer is able to interpret the physical layout of any drawn visual sentence and to provide a corresponding high level representation. Thanks to this capability the visual language designer may disregard the physical features and specify the language at a high abstraction level. VLPEG supports the rapid prototyping of visual environments and offers the designer the possibility to operate in automatic generation mode, by exploiting a grammar inference module. This capability allows the designer to focus on the structural features of the target language and quickly receive feedback from the customer during the language prototyping process