Cẩm nang dữ liệu không dây P18

SYSTEMS AND SUBSYSTEMS CONTROL APPROACHES The airlink subsystem is defined as the span between the user host’s connection point and the subscriber unit. It includes the service provider’s message switch/area controller, base stations, and the radio modem. There are (at least!) four current philosophical control approaches: 1. Decentralized: Nearby units are able to communicate with each other with no intervening infrastructure. As the distance increases, disrupting the information flow, nearby nodes pick up the transmitting signal. They hand off the data from node to node until a base capable of connecting to the wireline network is found. The message is...