<s>
The	O
AS	B-Protocol
7007	I-Protocol
incident	I-Protocol
was	O
a	O
major	O
disruption	O
of	O
the	O
Internet	O
on	O
April	O
25	O
,	O
1997	O
,	O
that	O
started	O
with	O
a	O
router	B-Protocol
operated	O
by	O
autonomous	B-Architecture
system	I-Architecture
7007	O
(	O
MAI	O
Network	O
Services	O
,	O
although	O
sometimes	O
incorrectly	O
attributed	O
to	O
the	O
Florida	O
Internet	O
Exchange	O
)	O
accidentally	O
leaking	O
a	O
substantial	O
part	O
of	O
its	O
entire	O
routing	B-Protocol
table	I-Protocol
to	O
the	O
Internet	O
,	O
creating	O
a	O
routing	O
black	B-Protocol
hole	I-Protocol
.	O
</s>
<s>
Probably	O
because	O
of	O
a	O
bug	O
in	O
the	O
affected	O
router	B-Protocol
,	O
the	O
routes	O
leaked	O
were	O
deaggregated	O
to	O
/24	B-Protocol
prefixes	O
,	O
which	O
were	O
more	O
specific	O
than	O
the	O
routes	O
originally	O
present	O
on	O
the	O
Internet	O
,	O
and	O
had	O
the	O
AS	O
path	O
rewritten	O
to	O
7007	O
,	O
leading	O
the	O
Border	B-Protocol
Gateway	I-Protocol
Protocol	I-Protocol
(	O
BGP	B-Protocol
)	O
used	O
by	O
the	O
Internet	O
's	O
routers	B-Protocol
to	O
prefer	O
the	O
leaked	O
routes	O
.	O
</s>
<s>
This	O
was	O
then	O
exacerbated	O
by	O
other	O
problems	O
that	O
prevented	O
the	O
routes	O
from	O
disappearing	O
from	O
other	O
networks	O
 '	O
routing	B-Protocol
tables	I-Protocol
,	O
even	O
after	O
the	O
original	O
router	B-Protocol
that	O
had	O
sent	O
them	O
had	O
been	O
disconnected	O
.	O
</s>
<s>
Analysis	O
of	O
this	O
event	O
led	O
to	O
major	O
changes	O
in	O
Internet	O
Service	O
Providers	O
 '	O
BGP	B-Protocol
operations	O
intended	O
to	O
mitigate	O
the	O
effects	O
of	O
any	O
subsequent	O
similar	O
events	O
.	O
</s>
