这题到底选哪个啊？？？

retest

QUESTION 130
Which three of these statements about penultimate hop popping are true? (Choose three.)
, }' ^5 Q" x+ ~0 ZA. It is used only for directly connected subnets or aggregate routes.
B. It can only be used with LDP.
) C' o) e% x8 G1 w6 X- K( ZC. It is only used when two or more labels are stacked.
D. It enables the Edge LSR to request a label pop operation from its upstream neighbors.
) G0 X7 m; {3 i6 u2 A7 OE. It is requested through TDP using a special label value that is also called the implicit-null value.
F. It is requested through LDP using a special label value that is also called the implicit-null value.

* |6 k: D2 `3 ?429和415这道题答案有冲突，该信哪个？？

brian0711

D, E and F{:soso_e101:}

retest

brian0711 发表于 2012-8-26 17:11
D, E and F

, N5 W+ p0 E& p7 Z2 z, G( p. V3 U- ^确认吗？？

hugo_520

def

5ibob

yiyi32373614

ADF      TDP  没有implicit-null
, n1 ?1 r9 ]2 b- r. f6 ~