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<DIV><TT><FONT face=Arial size=2>N. Richard Solis
wrote:</FONT></TT></DIV><TT><FONT face=Arial size=2></FONT><FONT face=Arial
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<DIV><BR></TT>> Yeah yeah yeah. I know that everything isn't
simple. I actually worked at a power plant so</DIV>
<DIV>> none of this is new to me. Can cascading failures occur?
Yes. Witness the Great Blackout in</DIV>
<DIV>> NYC. My point was that there are places where the electrical
network is designed to "blow the</DIV>
<DIV>> bolts" to TRY and protect everything. Does it work? Most
of the time, yes. All of the time?</DIV>
<DIV>> NO.<BR></DIV>
<DIV><FONT face=Arial size=2>Bringing this back to topic. What you are refering
to is similar to a failure within an AS. When you start having problems within
one section of your network that could jeapordize the rest of your network, you
cut it off until the problem can be fixed. Does it work? Most of the time, yes.
All the time? No. Sometimes the failure is too rapid to avoid the cascade
failure within the AS. This practice is seprate from grid and AS
interconnects.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV>> It is a complicated problem but you'd be suprised at how fast things
can happen when you</DIV>
<DIV>> HAVE to keep the system running. There is a tremendous amount of
skill concentrated in that</DIV>
<DIV>> field and they do a good job of keeping everything running well.
How many turbine overspeed</DIV>
<DIV>> events do <snip></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I agree. The same can be said for many networks.
The difference is that dealing with some networking problems is new to many
engineers. Without proper training and expecting a cascade failure, how do you
know the fastest method to deal with it? I've had lots of practice on my
network. I have an average stabalization rate of about 5 minutes now, but then,
I redesigned my network a long time ago to effectively deal with such problems
in a shorter time span.</FONT></DIV><FONT face=Arial size=2></FONT><FONT
face=Arial size=2></FONT><FONT face=Arial size=2></FONT><FONT face=Arial
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<DIV><BR>> The loss of a single transmission line isn't going to cause a
whole station to trip. If you're losing a</DIV>
<DIV>> bunch though, you've probably got lots of other problems to worry
about.</DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Also true with many networks today. However, this
topic falls within a single grid. The original analogy was dealing with grid
interconnects which have different requirements and must be protected at all
costs. IF, and I don't think it's happened in a very long time, an entire grid
lost integrity, it would be unacceptable for the grid to cascade into the other
two grids. Extra percautions are put into place. In the same reguards, many
Autonomous Systems do have different policies reguarding their interconnects
compared to their internal network.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>-Jack</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
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