Comcast, dismayed at being blamed for Pirate Bay's downtime, apparently helped fix it. Torrentfreak reports:
Initially The Pirate Bay team suspected that Comcast might be filtering PMTU responses, but Comcast looked into this and ruled it out. … Comcast reached out to Serious Tubes Networks, who deliver transit to The Pirate Bay, and they were able to correct the issue.
"Comcast emailed our NOC about their users complaining about not reaching The Pirate Bay. We resolved the issue and TPB can now be reached from Comcast," the CEO of Serious Tubes Networks told TorrentFreak.
Companies that sell blanks and hoses have always known their customers are pirates. But this hose also happens to be the majority stakeholder in NBC.
Update: Serious Tubes says that Comcast "did not help us fix Pirate Bay" and that the problem was caused by Global Crossing, another big telco.
Comcast did not help us fix The Pirate Bay. The problem was GBLX using reverse path filtering. We shut down one of our transits because it was flapping. The result was that all outgoing traffic to GBLX got filtered even though the packets took the same path as before. The Pirate Bay is using different paths for incoming and outgoing traffic to avoid beeing traced. We don't even know where their servers are. We resolved the issue by activating our other transit again.