A novel branching unit provided. The branching unit may include a first port for connecting a first power conductor disposed in a first optical cable, a second port for connecting a second power conductor disposed in a second optical cable, and a third port for connecting a third power conductor and a fourth power conductor disposed in a branch cable. The third port may include a first sub-port and a second sub-port. The first sub-port may be configured to connect the third power conductor of the branch cable. The second sub-port may be configured to connect the fourth power conductor of the branch cable.