One of the reasons that centralized nameservers get used for big dialup ISPs (such as Mindspring, Sean's earlier example) is that the folks who provide outsourced dial ports often don't put a nameserver in each POP, or are at least bad about giving their customers a map of them so the RADIUS servers can do the right thing. An unfortunate side-effect of this practice is that it can pessimize Akamai service (can't speak for DI and other CDNs). ---Rob