单项选择题
In order to avoid misconnections due to a failed node in a Bidirectional Line Switched Ring (BLSR), Alarm Indication Signals (AISs) are sent on every channel normally terminating in that node. What is the name of this process?（）
A. trunking B. squelching C. nodal bypass D. bridge and roll E. node failure insertion
单项选择题 How is UPSR and BLSR traffic rerouted during a protection switch when a complete fiber cable cut occurs?（）
单项选择题 What protection method is used in 4F BLSR networks?（）
单项选择题 Which is a legitimate bandwidth matched pair?（）
