Click the Exhibit button. Given the information shown in the exhibit, when creating 2 DS1 circuits, how many STS ports are used on the VT1.5 matrix at Node 1 as VT circuits and how many are used after using VT tunnels?（）

单项选择题A customer wants to create a 1:1 protection group with a DS3N-12 card. Which card slots would allow for a 1:1 protection?（）

A. Slot 2 and Slot 4
B. Slot 4 and Slot 6
C. Slots 5 or 13 only
D. Slot 16 and Slot 17

单项选择题Click the Exhibit button. Which type of protection is shown in the exhibit?（）

A.1+0
B.1+1
C.1：1
D.1：N

单项选择题You are provisioning a DS-1 circuit on an ONS 15454 UPSR configuration and XC-10G card. How many total VT ports are used within the VT matrix at the source node?（）

A.0
B.1
C.2
D.3
E.4

单项选择题What is the correct relative switching priority in a BLSR ring (higher to lower)?（）

A. signal fail, signal degrade, manual switch
B. signal degrade, signal fail, manual switch
C. protection lockout, manual switch, path AIS
D. forced switch, manual switch, signal degrade
E. protection lockout, manual switch, forced switch

单项选择题Why is an OC-3 2F-BLSR not feasible?（）

A. Switch times would exceed 50 ms for an OC-3 BLSR ring.
B. An equal amount of working and protect bandwidth is required.
C. DCC bandwidth is not large enough to handle K1/K2 processing.
D. There is not enough bandwidth in an OC-3 ring to justify BLSR protection.