Everywhere messaging

By "everywhere messaging" we refer to the ability to send and receive elect ronic communication at any time and through a variety of means, including w ired and wireless computer networks, voice telephones, end pagers. Our goal is to design messaging systems in which the receiver is always "on" and av ailable, and messages are correctly chosen for unintrusive delivery. But ev en in the office, and especially out of it, message arrival must compete in the real world with other activities that place demands on users' cognitio n and for which message alerting may itself be a distraction. In this paper we consider four experimental projects in terms of their ability to meet e verywhere messaging requirements of minimizing interruption, adaptation to the user, location awareness, and unintrusive user interfaces. These projec ts demonstrate message filtering, location-specific delivery, flexible audi tory alerting, and operation in, and monitoring of, a heterogenous networki ng environment.