Internet's resistance to modeling/measurement evolution-based (good!) reasons protocols, technologies, applications independently developed and deployed by no means synergistic by all accounts rapid `punctuated' but no equilibrium "have done fine without modeling so far" (let's wait till modeling cheaper than bandwidth) but simulation/analysis validation (& lately other stuff) needs data right granularities hard to come by measurement technology just not there argument for it also not there "helps everyone", but who pays? losing battle?