单项选择题
A.255 B.512 C.1024 D.4096
Which timing mode is most appropriate for an ONS 15454 ...
单项选择题Which timing mode is most appropriate for an ONS 15454 that has lost its BITS-1 and optical references?（）
A.line timing B.loop timing C.internal timing D.through timing E.external timing
You are provisioning a DS-1 circuit on an ONS 15454 2F-...
单项选择题You are provisioning a DS-1 circuit on an ONS 15454 2F-BLSR with a XC-10G card. Each VT1.5 connection must also terminate via the STS matrix. On the originating circuit node, how many STS ports are now available for VT1.5 circuits?（）
A.2 B.3 C.4 D.20 E.22 F.24
A customer has 2 DS1s to add between adjacent nodes in ...
单项选择题A customer has 2 DS1s to add between adjacent nodes in a UPSR ring. What type of circuit should you recommend?（）
A. VT circuits B. STS circuits C. VT tunnel circuits D. 1:1 protection circuits E. 1:N protection circuits
