1·It sets up encryption, integrity verification, and (optionally) compression and exposes to the upper layer an API for sending and receiving plain text packets.
它设置加密、完整性验证和(可选)压缩并向上层公开一个用于发送和接收纯文本数据包的API。
2·The scientists posit that these meteor strikes may also have triggered the flow of hot rock in the upper layer of the mantle right below the Earth's crust that is seen up to the present day.
科学家们断定，这些流星的冲击也可能触发了刚好低于地球地壳的地幔上层里的热岩，这就是至今我们所能看到的。
3·For this upper layer we set the transparency to 20% so the background will be nearly black.
我们对于这个上层的透明度设置为20%，这样的背景将是近黑色。
4·Place the tray in the bottom of the box, put the cup, bowl and put it in the upper layer of the box.
放入时把盘子放在最下面，把杯、碗具倒放入箱子的上层。
5·For the development of upper layer communication protocols and application software, this system also provides wireless communication interfaces and application program framework.
为了更好地支持上层通信协议和应用软件的开发，该系统还提供了无线通信接口和应用程序框架。