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Handbook on Mobile and Ubiquitous Computing: Status and Perspective
Services can also be provided by the alpha-pads themselves. Therefore, there are five different
access protocols. The first one considers the case in which a normal device wants to access a service
provided by the alpha-pad that bound it (and the opposite; an access request from an alpha-pad to
a normal device it has bound before). The second one when both the requester and the provider are
normal devices bound by the same alpha-pad. The third one when an alpha-pad is used to access
a service provided by another alpha-pad with which it shares a mutual binding. The fourth case
involves an access request from a normal device to an alpha-pad with which the requesting device
does not ...