Final answer:
The Path Computation Element Protocol (PCEP) is used for communicating LSP and status information between the NorthStar Controller and label edge routers in a network.
Step-by-step explanation:
The protocol used to communicate Label Switched Path (LSP) and status information between the NorthStar Controller and label edge routers is called the Path Computation Element Protocol (PCEP).
The NorthStar Controller is an advanced traffic-engineering solution that utilizes PCEP to query and control LSPs within a network for optimized path computation. Label edge routers, which serve as the ingress and egress points for LSPs, interact with the NorthStar Controller through PCEP to establish, maintain, and modify those paths according to network policies and conditions.