MPLS VPN is an IP virtual private network based on multiprotocal label switching in which MPLS is applied on network routing and switching

DiffServ and Traffic Engineering （TE） are the two technologies used for providing QoS in MPLS network

which are analyzed in this paper

and some of application scenarios are presented that can not be solved using DiffServ or TE alone. MPLS-TE must operate at the aggregate level across all the DiffServ classes of service and for that MPLS DiffServ-aware TE is developed to build TE trunk on a per class base.