An optical communication system with both EDFA and B DFRA is introduced. Two applications of B DFRA are studied. The first case is a receiver terminal with a receiver, an EDFA preamplifier and a B DFRA. The second case is a multistage point to point optical repeated system with both EDFA and B DFRA. The performance improvements in the two cases are calculated. The principle of the Raman pump power selection is discussed.