Constraint in Eq. (6) maintains the number of splutters in the network, which depends on the number of OLTs in the CO. Equation (7) indicates that the splutter should be placed at potential location z if there is an optical path from splutter at potential location z to ISCW at potential location x . Equation (8) ensures that if an optical path exists from a splutter at potential location z to ISCW at potential location x , this splutter should connect to an OLT. The constraint expressed in Eq. (9) maintains that each ISCW needed should be placed at the potential location. Equation (10) ensures that the number of ISCWs connecting to the splutter should not exceed the split ratio of this splutter. Equation (11) maintains that if a splitter is placed at a potential location z , this splitter should connect to at least one ISCW.