Abstract: MPLS VPN is the mainstream of present virtual private network technology. In order to transmit the integration of voice, video and critical data in MPI_S VPN, the key is to achicvc cffcctivc QoS guarantcc. Based on the study on DiffServ and MPLS TE,it introduced the MPLS DS-TE. By combining the differentiated Services of DiffServ with the effective end-to-end routing strategy of MPLS TE, and employing the bandwidth constraints model, DS-TE achieves QoS guarantee of end-to-end and differentiated Services in MPI_S VPN.

Key words: MPLS VPN, QoS, DiffServ, MPLS TE, DS-TE