A.When the standard SSM protocol is started, the clock network can be configured in both directions but cannot be looped.

B.When the extended SSM protocol is started, the clock network can be configured in both directions and can be looped.

C.When the SSM protocol is not enabled, the clock network can only be configured as one-way and cannot be looped.

D.Whether to start the SSM protocol has little effect on the clock network.

A.Avoid communication by extended ECC mode between each subnet gateway network element.

B.When setting the ECC extended mode remotely, you must ensure that the settings are correct in order. Otherwise, the unmanaged network element will not automatically resume communication with the network management system and must be reset to the site.

C.The ECC extension mode of the remote NE must be modified first, and then the ECC extension mode of the gateway NE is modified.

D.It is not recommended to set the gateway NE as the server. It is recommended to set the NE closest to the gateway NE as the server NE.

A.+1dBm

B.-2dBm

C.+7dBm

D.+4dBm

A.OTN provides high-speed interfaces of 2.7 Gbit/s, 10.7 Gbit/s, 43 Gbit/s and even 111.8 Gbit/s.

B.OTN provides up to five levels of nested or overlapping TCM connection monitoring.

C.OTN provides powerful out-of-band FEC function to effectively ensure line transmission performance.

D.WDM function is used to meet the requirement of Tbit/s bandwidth per fiber.

A.In the packet transport field, the MPLS technology is mainly used to construct tunnels to carry various types of services (for example, TDM, ATM, and Ethernet) transmitted by PWE3 to implement end-to-end transmission of services on packet networks.

B.MPLS packet forwarding is based on labels.

C.MPLS is not a service or application. It is a standard routing and switching platform that supports various upper-layer protocols and services.

D.MPLS has two planes: control plane and forwarding plane. The control plane is connection-oriented, the forwarding plane is connectionless.