An LSP (Label Switched Path) that needs to be explicitly configured on the head-end router is referred to as a PCC-initiated LSP. In this context, PCC stands for Path Computation Client, which is typically the head-end router that requests path computations from the PCE (Path Computation Element). Therefore, for a PCC-initiated LSP, the configuration starts at the head-end router, distinguishing it from other types of LSPs that might be initiated or managed differently.