I was just thinking about the SW Bell cable cutting/Bergen Brunswig robbery while watching this unfold. The minute they said there was an AT&T building on that street I looked it up on Google Maps, and saw about where the bomb was placed, a non hardened/reinforced service entrance that's probably where the back up generator is located. You don't have to bring the building down to create a problem, and sadly I doubt that any of the old Bell System switch centers like this one, have any reinforcement, and I also have serious doubts about their disaster recovery plans.
https://goo.gl/maps/kskWEqRpL2AzqbLk9I kept waiting for the next shoe to drop knowing that they just shut down most all major communications in that area of the state. I was thinking that there was going to be some other action taken.