Two modes of communication, one is PPI master - slave protocol, one is free port protocol.

通讯方式主要有两种：PPI主从通讯、自由口模式通讯。

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RFCOMM is known as the virtual serial port protocol because it allows a Bluetooth device to simulate the functions of a serial port.

RFCOMM称作虚拟串口协议(virtual serial port protocol)，因为它允许蓝牙设备模拟串口的功能。

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Collecting card of image and data based on parallel port protocol (EPP) can be applied to notebook PC and make data collecting equipments more portable.

基于并口epp协议的图象数据采集卡适用于笔记本电脑，从而使数据采集设备具有便携性。

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Security solutions based on physical infrastructure, and policy expressed in terms of a particular device, the corporate PC, an IP address, network port, or application protocol are becoming useless in a mobile, borderless world.

FORBES: Going Mobile: Security in the Age of Ubiquity