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14(router)m15(address)m14(incurs)m0 1337 p (additional)s10(cost)m11(during)m10(the)m11(routing)m10(table)m10(build)m11(process)m10(\(Section)m11(16.4\).)m0 1405 p (Besides)s12(preventing)m12(extra-hops,)m13(there)m12(are)m12(two)m12(other)m12(applications)m12(for)m12(this)m12(\014eld.)m19(The)m12(\014rst)m12(is)m12(for)m12(use)m13(by)m12(\\route)m12(servers".)m0 1455 p (Using)s12(the)mt-bol.300 @sf 11(forwarding)m12(addr)m(ess)st-rom.300 @sf 44 c12 r 97 c11(router)m12(in)m12(the)m11(middle)m12(of)m12(the)m12(Autonomous)m11(System)m12(can)m12(gather)m12(external)m11(routing)m12(infor-)m0 1505 p (mation)s9(and)m10(originate)m9(AS)m10(external)m9(advertisements)m10(that)m9(specify)m10(the)m9(correct)m10(exit)m9(route)m10(to)m9(use)m10(for)m9(each)m10(external)m9(destination)m0 1555 p (\(Section)s10(2.2\).)m0 1622 p 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