mobile access remains limited by relatively short battery power lifetime, expensive wireless bandwidth and areas with difficult or no continuous communication coverage. it is believed that as many as 70% of laptop users would operate in planned or non planned disconnected mode. although existing approaches have led to implementing disconnected mode operation within applications, we chose to introduce changes to a mobile extension of the internet transport protocol. we show through simulation that this protocol performs better than tcp. in order to evaluate disconnection parameters including disconnection and inter-disconnection times, a performance study of disconnection is presented. finally we argue that disconnection is an important service and should therefore be considered as a quality of service (qos) parameter to be negotiated among mobile and fixed communication entities.