Joel on Software is a good blog, but in his most recent post he makes an unfortunately common mistake.
He call's his ISP (peer1) a "tier 1 provider".
Now, that sounds impressive (and so lots of marketing departments like to call the network they represent "tier 1"), but there's actually a precise technical definition of tier 1. Peer1's network information page says that they have four tier 1 upstream providers but tier 1 networks, by definition, have no upstream providers. This means that they're not running a tier 1 network. This doesn't mean that they're not running a really good network (in fact, there are experts who would recommend connecting to good tier 2 networks instead of tier 1 networks to avoid problems that can happen when there are peering disputes between tier 1 networks).
