A、Interfaces have a default metric of 1.
B、Level 1 is intra - area and level 2 is interarea.
C、Level 1 routing is between an end system (ES) and IS while Level 2 routing is between an IS and IS.
D、Hosts send ISHs while routers send ESHs.
E、IS - IS is an open standard.
F、Metrics depend on interface speed.