Carafe does not make any assumption on which layers may be involved in a bridge fault. Therefore, the pairs of layers that can be bridged together must be listed in this section. Each line in this section defines one kind of bridge that can occur. A line contains the names of the two layers that can be bridged together and, of course, they must be defined in the types section. For intra-layer bridge faults, the same layer name is given for both layers.