I am an avid learner to MPLS protocol . I just have a question to ask that when ldp is configured on PE routers within MPLS domain, after exchanging hello messages and building adjacencies , neighbor routers learn about FEC's and the routers locally build their LIB also in that process prior to building they have to advertise thier FEC in MPLS domain but after building their LIB do they also advertise their Label-bindings like service id specific to a service/applciation for example when VWRN payload arrives at PE1 and it needs to be trasnported inside MPLS domain PE2 is the destination . How would PE2 knew about same service id ?