On March 28th at 17:52 UTC, we saw the peering link between Telia and Cogent come back up. Recently, peering disputes, especially with Cogent, tend to be all about traffic ratios: as long as both parties send roughly the same amount of traffic to each other, life is good. But when the ratios get out of whack, someone's feelings get hurt (more specifically someone's business model is threatened). Before the de-peering, we would typically see Cogent using Telia to reach around 2700 networks (prefixes). Now that count has dropped to just about 1450 networks. On the other hand, Telia used to reach approximately 7000 networks via Cogent and that number has now increased to almost 8600. So was Cogent sending too much traffic to Telia before? Did Telia then do something to provoke Cogent to turn them off (like send a bill)? We'll never know definitively, but someone blinked and the Internet is now whole again.

While this is good for the Internet, Cogent claimed that this dispute was about capacity issues and no one orders and installs new high capacity circuits in a week, especially during a contract dispute. So if there was a capacity issue, there is still a capacity issue. As a result, the situation is bound to be very fluid for the next few weeks. We'll update this blog as we analyze the resulting shifts in routing.