
Perhaps nothing is taken more for granted than the telephone. Whenever you pick it up, you just assume it will work. But there are many elements in a telephone network, and they all must be integrated. Whether it's signaling, switching or channeling, so many things need to go...

Perhaps nothing is taken more for granted than the telephone. Whenever you pick it up, you just assume it will work. But there are many elements in a telephone network, and they all must be integrated. Whether it's signaling, switching or channeling, so many things need to go...