•ermits upper level protocols and applications to transmit and receive upper layer data packets up to 23 bytes in length
允许上层协议和应用程序传输和接收上层数据包直到23个字节的长度
•rovides channel management, allowing for logical channels between two endpoints, supported by the link layer
提供了渠道管理,允许两个端点之间的逻辑通道,支持链路层