| 摘要 |
<p>PURPOSE:To report the congestion and the call state in a link for user identification information by using an invalid frame to be disposed on the frame relay network in the full chain system. CONSTITUTION:If a congestion occurs in an FR exchange 3 when data is sent from an FR terminal 1 (rooter or the like) to an FR terminal 2, the FR exchange 3 sets the FECN bit of the FR frame to be repeated from '0' to '1'. Thus, the FR terminal 2 knows that the frame sent from the FR terminal 1 passes the congestion point and the FR exchange 3 sends a frame setting the BECN bit to '1' to the FR terminal 1. The frame to be sent is taken as an invalid frame having no information field and an originating FR exchange 4 checks the frame error of the received frame and recognizes it as a frame to be disposed. After confirming the BECN bit of the address field, it ejects the invalid frame.</p> |
