单选题UPSR protection switching is initiated by （）, while BLSR is initiated by （）.A the K1 SONET byte； the K2 SONET byteB the K2 SONET byte；the K1 SONET byteC transmitter switching；receiver detectionD Line Overhead bytes；Path Overhead bytesE Path Overhead by

A. the K1 SONET byte； the K2 SONET byte

B. the K2 SONET byte；the K1 SONET byte

C. transmitter switching；receiver detection

D. Line Overhead bytes；Path Overhead bytes

E. Path Overhead bytes；Line Overhead bytes

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

A.after a packet is identified by a multifield classifier

B.after the traffic passes though a shaper

C.prior to ingress policing of traffic

D.while the packet is stored in the switching fabric of the router

Click the Exhibit button. A customer has several interconnected core rings (see exhibit). They want to create several irtual rings?utilizing their OC-192 backbone (nodes 1,2,3,4). What should you recommend?（）

A. PPMN with BLSR rings

B. PPMN with UPSR rings

C. 1:N protection on all core circuits

D. multi-ring interconnect with BLSR rings

A. VT circuits

B. STS circuits

C. VT tunnel circuits

D. 1:1 protection circuits

E. 1:N protection circuits

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.

The objective of information （ ） includes protection of information and property from theft，corruption，or natural disaster，while allowing the information and property to remain accessible and productive to its intended users.

A. concurrency B. integrity C. consistency D. security