In the book Brave New World, what does the electric wire around the Reservation symbolize?

This is a tough one... but to me, the electrified fence
that the Warden tells Bernard and Lenina about symbolizes technology separating the
"civilized" world from the "savage" one.

To me, this book
really emphasizes the way in which it is technology that has changed the society and
made it into the brave new world.  That means that it is technology that stands between
the old ways and the new ways.  I think that it is important the fence is electrified --
that shows how technological it is in nature.

So I see the
fence as a symbol of what it is that distinguishes the savage society from the
civilization.