TDM is a physical layer concept, it has no regard for the nature of the information that is being multiplexed onto the output channel. 分時多工屬於實體層的概念，當資料被多工處理送到輸出通道，是不需要理會資料種類的。
WAN standards typically describe both physical layer delivery methods and data link layer requirements, including physical addressing, flow control, and encapsulation. 廣域網路標準典型地描述實體層的傳送方法和資料鏈結層的需求，包括實體層定址，流量控制和封裝。
The freedom tone allows the ascension to be anchored in the physical. 自由音調允許提升在物理層上被錨定。
What types of intentions require immediate relaying back to the physical? 哪些類型的意想需要立即重置回物理層？
