The future National Information Infrastructure will include technologies for WAN and LAN access that are both faster and slower than current voice and data technologies. For example, ATM will offer high-speed data rates on a fixed wired infrastructure and will increase the availability of multimedia voice and audio applications.
Mobile computing is different for a number of reasons.
By definition, mobile nodes are not tied to a wired infrastructure. They may roam from one network to another. This presents any number of challenges at all layers of the network stack. At the application layer, applications will have to learn how to deal with disconnection from the wired infrastructure. At the network layer, IP addresses will no longer correspond with a fixed location.