默认题库 - CCNP(642-311)

多选题

What are two characteristics of dual-ring interconnect in SONET networks? （）(Choose two.)

A. It protects signals against node failures between rings.
B. It protects signals against node failure within a single ring.
C. It allows for traffic to be preempted when a ring switch occurs.
D. Traffic can be dropped and continued at interconnecting nodes.
E. It protects preemptible traffic from being dropped when a ring switch occurs.

查看答案

多选题

What are three factors that limit the maximum distance of an amplified optical signal without regeneration? （）(Choose three.)

A. fiber dispersion
B. signal attenuation
C. transmitter power
D. amplifier bandwidth
E. receiver dispersion tolerance

查看答案

多选题

What are two important considerations when using 2- or 4-channel 15216 OADMs?（） (Choose two.)

All "Add" channels require uniform power levels.
B. The flexibility of wavelengths per OADM is limited.
C. It is easier to balance "Pass-Through" and "Add" channels.
D. There is lower pass-through loss using multi-channel OADMs.
E. You can extract a single channel without dropping other channels.

查看答案

多选题

What are three relevant design considerations when using the 15216 EDFA? （）(Choose three.)

A. dispersion
B. Optical SNR
C. span attenuation
D. four wave mixing
E. receiver sensitivity

查看答案

单选题

How is UPSR and BLSR traffic rerouted during a protection switch when a complete fiber cable cut occurs?（）

A. Traffic is switched from the first node receiving the AIS indication.
B. Traffic is switched from the far side of the failure, allowing handshaking to occur.
C. UPSR traffic is switched from the terminating node, BLSR traffic is rerouted from the originating node in the ring.
D. UPSR traffic is switched from the terminating node, circuit by circuit. BLSR traffic is rerouted from the last reachable node in the ring.

查看答案

单选题

A Channel ID mismatch occurs when （）.

A. fibers are terminated incorrectly on a node
B. the channel number in the received K1 byte is not identical to the channel number transmitted in the K2 byte
C. the channel number in the received C1 byte is not identical to the channel number transmitted in the C2 byte
D. the channel number in the received C2 byte is not identical to the channel number transmitted in the C1 byte
E. the channel number in the received K2 byte is not identical to the channel number transmitted in the K1 byte

查看答案

多选题

What three in combination are factors that can cause four-wave mixing in fiber-optic cables? （）(Choose three.)

A. low optical power
B. high optical power
C. few optical channels
D. many optical channels
E. low chromatic dispersion
F. high chromatic dispersion
G. too much power differential in the optical channel

查看答案

单选题

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.

查看答案

多选题

Which three timing modes are supported on the ONS 15454 shelf? （）(Choose three.)

A. line timing
B. loop timing
C. internal timing
D. through timing
E. external timing

查看答案

多选题

Which three technologies are used to reduce chromatic dispersion accumulation in fiber-optic transmission systems? （）(Choose three.)

A. PIN photodiodes
B. zero-chirped lasers
C. Erbium-doped fiber amplifiers
D. dispersion compensating fiber
E. dispersion compensating Bragg grating

查看答案