在環狀一向的通訊設備故障時,ATM交換機將中繼電路路由自動切換到另一向,但當所有用戶電路全部導向一端時,將導致ATM交換機中繼電路頻寬變少,在用戶滿載時有可能會產生用戶電路因頻寬不足無法順利切換;本論文將討論在不增加介面卡板設備及不擴增中繼傳輸設備電路情況下,以現有設備採取調整電路方式用最少經費完成解決問題,看似簡單然而牽一髮動全身,環狀中全部ATM幹線核心交換機中繼電路都將配合改接亦是大型通訊工程改造。
When there is a breakdown in some channel of the circle-shaped communication facilities, ATM exchanging machine can switch the relay circuit to the other channel automatically. However, it will reduce the bandwidth for the relay circuits of the ATM exchanging machine. When all the users are directed to one channel they may not be switched successfully, because there is not enough bandwidth when all the channels are fully loaded. In this thesis we will find some way out. Instead of increasing interface cards and broadening relay transmission circuit we solve these problems by the way of adjusting circuits with the existing facilities. It looks very simple. But a slight fluctuation in somewhere of transmission channel may affect the whole transmission channel. The main channels of ATM exchanging machines in the circle circuit need to operate in coordination with these adjustments.