On Mon, 04 June 2001, Simon Lockhart wrote:
Well, I assumed PSI and/or C&W would have had some backup transit, if they were going to play that game, but...
By defintion a "tier 1" provider does not have any transit, backup or otherwise. If tier 1 providers terminate peering, there are no alternate routes between them. However, customers who are multihomed may be able to reach both of them. Likewise customers of other peers can reach both of them. But customers exclusively connected to one or the other battling peer can't reach customers exclusively attached to the other. Its been a while since we've had a real "tier 1" peering battle. Last time ANS lasted a couple of weeks before they caved in and joined the CIX after the CIX filtered out non-member routes.