The Central Office (CO) to Central Office Connection are fiber links that essentially connect the Optical Distribution Frames (ODFs) in two Qnbn COs to one another. Thanks to this service the Customer can complete the access network of GPON and P2P fibers to the End users with an aggregation network that gathers all the data going and coming from the end users. This is a particularly technical requirement and would normally be used for a Service provider that requests it.