Key Concept #2: Dumb Network Original Internet design interior nodes (routers)have no knowledge* of ongoing connections going through them Not how you picture the telephone system works Which internally tracks all of the active voice calls Instead: the postal system Each Internet message("packet")self-contained Today's Internet is full of hacks that violate this7 Key Concept #2: Dumb Network • Original Internet design: interior nodes (“ r o u ters” ) h a v e no knowledge* of ongoing connections going through them • Not how you picture the telephone system works – Which internally tracks all of the active voice calls • Instead: the postal system! – Each Internet message (“packet”) self-contained * Today’s Internet is full of hacks that violate this