In optical channel transport unit overhead （OTU OH）， what are general communication channels 1 and 2（GCC1/GCC2） used for？（）

多项选择题WhichthreeofthesestatementsaboutPPPoEaretrue？（）

A.PPPoE can provide a host with access to a destination over Ethernet. You can have only one  PPPoE session per PVC
B.You must install PPPoE client software on all hosts that connect to the Ethernet segment. This means that the access provider must maintain a CPE
C.You cannot use PPPoE with Cisco Service Selection Gateway
D.PPPoE implementation is susceptible to broadcast storms and possible denial-of-service attacks
E.Per-session accounting is possible， which allows the service provider to charge the subscriber based on session time for various services offered. The service provider can also require a minimum access charge

单项选择题WhatistheorderofpreferenceforthesecommandswhenallofthemareappliedtooneneighborintheBGPinboundfilterdirection？（）

A.prefix-list， route-map， filter-list， distribute list
B.route-map， filter-list， prefix-list， distribute-list
C.route-map， distribute-list， prefix-list， filter-list
D.filter-list， prefix list， route-map， distribute list
E.distribute list， prefix-list， route-map， fitter list

多项选择题WhataretwouRPFworkingmodes？（）

A.express mode
B.safe mode
C.loose mode
D.strict mode
E.tight mode

多项选择题WhichfourstatementsaboutanIPservicelevelagreement（SLA）aretrue？（）

A.SLA responder knows type of operation， the port used， and duration.
B.SLA responder inserts in and out timestamps in the packet payload.
C.SLA sender and responder use the IP SLA Control Protocol to communicate with each other before
D.SLA sender and responder communication can be encrypted.
E.SLA sender and responder communication can be authenticated with MD5.

单项选择题WhichOSPFLSAisusedtosupportMPLStrafficengineering？（）

A.opaque LSA （Type 8）
B.opaque LSA （Type 9）
C.link LSA （Type 1）
D.network LSA （Type 2）
E.opaque LSA （Type 10）