The paper proposes an implementation architecture of DiffServ-over-MPLS traffic engineering (TE) on Intel IXP2400 network processor using Intel IXA SDK 4.0 Framework. Program architecture and functions are described. Also fast and scalable range-match classification scheme is proposed for DiffServ-over-MPLS TE that has been integrated with functional blocks from Intel Microblocks library. Performance test shows that application can process packets at approximate data rate of 3.5 Gbps. The proposed implementation architecture of DiffServ-over-MPLS TE on Network processor can provide guaranteed QoS on high-speed next generation Internet, while being flexible and easily modifiable.