  The problem of achieving common understanding between agents that use
different vocabularies has been mainly addressed by designing techniques that
explicitly negotiate mappings between their vocabularies, requiring agents to
share a meta-language. In this paper we consider the case of agents that use
different vocabularies and have no meta-language in common, but share the
knowledge of how to perform a task, given by the specification of an
interaction protocol. For this situation, we present a framework that lets
agents learn a vocabulary alignment from the experience of interacting. Unlike
previous work in this direction, we use open protocols that constrain possible
actions instead of defining procedures, making our approach more general. We
present two techniques that can be used either to learn an alignment from
scratch or to repair an existent one, and we evaluate experimentally their
performance.
