The TorrentFreak article explains enough about the architecture to understand that while it's possible to shut TPB down, it's much more difficult now. The steps involved are:
- Locate transit router.
- Obtain warrant for access to transit router.
- Watch to see where traffic is going to locate load balancer.
- Obtain warrant for access to load balancer.
- Watch to see where traffic is going to locate cloud provider(s).
- Obtain warrant(s) for access to cloud provider(s).
- Shut all three locations down simultaneously.
In the past, only steps 1. and 2. were necessary. Seeing as steps 2. 4. and 6. are likely to be in different countries and 6. could be in several countries at once on its own, this is likely to be comparatively very difficult.
It is also quite likely that TPB have cold spares of every part of this infrastructure. A spare transit router can be brought online with a simple DNS change. The new transit router can be pointed to the new load balancer quickly and cloud providers boast that new instances can be spun up in minutes. Even if everything were brought down at once by authorities, the website could be up and running again in a few minutes. There is no reason for there to be any link from the live infrastructure to the cold spare infrastructure so that would be undiscoverable by the authorities before the shutdown.
Yes, it is quite feasible.
Servers with encrypted disks leave at least two possibilities for accessing the data:
- Access the server while it's still running and the disks/keys are available in RAM.
- Break the encryption. While in the past we would have said this is infeasible, recent revelations of the NSA's long-term goals in subverting cryptography standards and software leaves this point uncertain.
Servers with no disks don't have this possibility.
TPB has already weathered what looks like a linchpin: the domain. This vulnerability has also been given a similar treatment with too many options (some hidden) for any authority to shut down.