Exam 400-007 topic 1 question 80 discussion

Chromatic dispersion is not an advantage but a challenge to overcome https://www.cisco.com/c/dam/global/de_at/assets/docs/dwdm.pdf

Should be B,C

as per the cisco docs

BC is correct

A& C. Topology Flexibility One recent core network trend is the consolidation of multiple Layer 2 and Layer 3 networks into a single IP/Multiprotocol Label Switching (IP/MPLS) infrastructure. Despite this Layer 2 and 3 convergence, the underlying transport layer (Layer 1) of many service provider core networks has continued to use SONET/SDH. Some network inefficiencies result from the way core transport networks are built out to support the IP or service layer over the SONET/SDH layer, supported by an underlying DWDM infrastructure. Protection Options A recovery time of less than 50 ms can be achieved mapping Ethernet directly over DWDM. https://www.launch3telecom.com/shared_media/datasheet/product_data_sheet09186a00801849e7.pdf

C & E. Topology Flexibility One recent core network trend is the consolidation of multiple Layer 2 and Layer 3 networks into a single IP/Multiprotocol Label Switching (IP/MPLS) infrastructure. Despite this Layer 2 and 3 convergence, the underlying transport layer (Layer 1) of many service provider core networks has continued to use SONET/SDH. Some network inefficiencies result from the way core transport networks are built out to support the IP or service layer over the SONET/SDH layer, supported by an underlying DWDM infrastructure. Protection Options A recovery time of less than 50 ms can be achieved mapping Ethernet directly over DWDM. https://www.launch3telecom.com/shared_media/datasheet/product_data_sheet09186a00801849e7.pdf

Two advantages of using Dense Wavelength Division Multiplexing (DWDM) over traditional optical networks are: Increased Capacity: DWDM allows for the multiplexing of multiple optical signals onto a single fiber, increasing the capacity of an optical network. This makes it possible to transmit a large amount of data over long distances without the need for additional physical fibers. Improved Reliability: DWDM provides a more resilient and reliable network by allowing for the transmission of multiple optical signals at different wavelengths over a single fiber. In the event of a fiber cut or other failure, the network can reroute traffic over a different wavelength, minimizing downtime and disruptions.