单项选择题
There are three IS-IS routers on a Gigabit Ethernet segment: Router A, Router B, and Router C. Each router is configured in the same area and each routers Gigabit Ethernet interface is configured for Level 1-only. Router A is the Designated Intermediate System (DIS). Each routers IP address on that segment is: Router A: 10.1.1.1/24 Router B: 10.1.1.2/24 Router C: 10.2.2.1/26 Which statement is true about all the adjacencies that exist on that LAN?（）
A. No routers are adjacent with each other. B. Only Router A and Router B are adjacent at Level 1. C. Only Router A and Router B are adjacent at Level 2. D. All three routers are adjacent with each other at Level 1.
单项选择题 In IS-IS, how long will the restart helper keep the restarting router in the up state?（）
单项选择题 What is the function performed by LSA Type 1?（）
单项选择题 On what is the Martini control plane based?（）
