TULIP
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Trilateration Algorithm
minRTT = propagation delay + extra delay (due to extra circular routes , congestion and router delays)
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f(x0) . ( x- x0) f ' (x0) . (x - x0)
f( x ) = f (x0) + - -------------- + ---------------------
1! 2!
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f ( x ) = f (x0) + f' (x0) delta 
( x ) .......................(3)
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d()EstDi. delta ( x ) d(EstDi) . delta
PDi = Est Di + --------------- + ------------------
dX dY
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ODi = Est Di + -------------. delta ( x ) + ---------------- - delta ( y) + c. delta(to)
dX dY
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