This standard consists of distinct Fibre Channel mappings resulting in the following models: ?C FC-BB_IP (FC over TCP/IP backbone network) ?C Transparent FC-BB consisting of: ?C FC-BB_GFPT (FC over SONET/SDH/OTN/PDH backbone network using GFPT adaptation) ?C FC-BB_PW (FC over MPLS network using PW adaptation) Figure 1@ figure 2@ and figure 3 illustrate the scope and the major components of the FC-BB-4 models and their relationship to the IETF and ITU-T standards. Table 1 shows the organization of this standard. FC-BB_IP and Transparent FC-BB do not interoperate in any way and are independent models.