Which statement is true about IS-IS?
A.
IS-IS level 1 internal routes are announced to level 2 by default.
B.
All IS-IS level 1 routes are announced to level 2 by default.
C.
IS-IS level 2 internal routes are announced to level 1 by default.
D.
IS-IS does not share routes between level 1 and level 2 by default.
Explanation:
External L1 routes are not advertised to an L2 area by default
– Route leaking policies are used to modify this default behavior
– Using only wide metrics eliminates internal/external distinction
Sorry Ong, but L1 routes are internal…
External L2 routes are not advertised to an L1 area by default
So, A is correct