It was a network of some kind that provided automatic access to the OP to many ter'angreal, vehicles etc. - the OP equivalent of a power grid. It's the answer to a question that puzzled quite a few AS: how is it that non-channellers in the AOL are said in books to have been able to use ter'angreal?

How it worked exactly is unknown. It was probably very high tech devices, able to draw the OP (like the BOW drew saidin on its own once activated), to regulate the quantities used by each OP object, and to separate the different flows needed by each ter'angreal.

As this was used for planes and ground vehicles as well as wireless devices (like callboxes and the pager of Alviarin), most people believe this worked more like cell phone towers, a series of devices creating a net of OP access over all areas of the world, rather than like electricity, needing to be transported to each home etc.

All we know beyond that is that the standing flows were disrupted at some point during the WOS.