PREFER_ME Global Community?
2
0
3
1
2 5 1 4 7 0
2 0
1 3 6 0
1 4 7 0
3 2 0
3 6 0
shortest paths,
no transit across 3
Import only from 1,
no transit across 3,
send PREFER_ME
to 2
shortest paths
shortest paths,
no transit across 1
Imagine a world with no
LOCAL_PREFERENCE but
with PREFER_ME …
A single AS can use
PREFER_ME to create
a “BAD GADGET” even
when others are doing
vanilla routing.
Does PREFER_ME make
it easier to do bad things?
Guidelines for safe use
of PREFER_ME?
Ties at 1 and 3 are broken by next-hop address...
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