No, a lot of AT&T buildings were built as bunkers, well blockhouses, during the Cold War. The typical "reinforced" criteria was being able to handle 2-3psi over pressure and storm force winds (70mph).

This particular building is an old AT&T-cum-BellSouth-cum-AT&T tandem office. It's where end offices (that connected to actual customer phones) would be connected together and connected to inter exchange carriers.

AFAIK AT&T tended to build their tandem offices as reinforced style buildings. They are larger than end offices and needed high availability because they were the central node for a region's telephone network and its connection to other networks.

I don't think I've ever seen any central office in a regular home in a neighborhood. Even end offices, while smaller than tandems, required a lot of equipment and power backups. Besides the equipment in the building they'd usually have secured parking/storage for service vehicles.

"Central Office" is the wrong term for it, but I've worked in a couple switching offices that were built to look just like another house in the tract. They were RSUs (Remote Switch Unit), that trunked everything back to a parent CO.

In both cases it was a housing tract that was allergic to ugly buildings or something. The vast majority of RSUs looked like smaller versions of the CO. Gray cinder blocks and asphalt.

That's interesting, I've only ever seen cross boxes (ugly green boxes) with RCUs in them. Then again I may have seen tons of disguised RSUs and never have known it.

To anyone interested, see "Anaheim 17"

http://www.thecentraloffice.com/calif/OC1/OCP.htm