The automatic deduction of strategies for on-line software extension

The on-line environment that the IOLE project is to provide implicitly includes the specification of some suitable hardware (HW) architecture. The IOLE project in fact is also to focus current trends in HW design, so as to single out adequate existing processor architectures suitable for Integrated Broadband Communications (IBC), bearing in mind that any future IBCN shall be both multi-country and multi-vendor. The future IBC systems must provide a high degree of flexibility, permitting software changes for the purpose of introducing new services or modifying existing ones. At the same time, IBC systems must offer a high degree of availability. In order to cope with both requirements, on-line software extension mechanisms are needed that offer the possibility to add, delete or replace software within a system without disturbing the activities carrying real traffic. The paper presents initial steps towards a methodology for determining an extension strategy, i.e. a plan for the execution of the extension, to guide the on-line replacement of a particular software component