Câu 21: 642-883: Deploying Cisco Service Provider Network Routing (SPROUTE)

In which network environment is IS-IS adjacency check important?

1. A. in a multitopology environment where there are different instances of IS-IS running on the same router
2. B. in an IPv4/IPv6 environment and running single-topology IS-IS — đáp án hiện tại
3. C. when a level L1/L2 IS-IS router is neighboring with a Level 1 only or Level 2 only router
4. D. when IS-IS neighbors are in an NBMA environment like over Frame Relay
5. E. when IS-IS neighbors are in a broadcast environment like an Ethernet LAN