Résumé
This paper defines and exemplifies a new computational abstraction called i-dialogue which aims to model communicative situations such as those where an agent conducts multiple concurrent conversations with other agents. The i-dialogue abstraction is inspired both by the dialogue abstraction proposed by O'Donnell in 1985 and by the STROBE model by Cerri in 1996. Idialogue models conversations among processes by means of fundamental constructs of applicative/functional languages (i.e., streams, lazy evaluation and higher order functions). The i-dialogue abstraction is adequate for representing multi-agent concurrent asynchronous communication such as it can occur in service providing scenarios on today's Web or Grid. A Scheme implementation of the i-dialogue abstraction has been developed and is available.