%% You should probably cite draft-ietf-idr-bgpls-sr-vtn-mt instead of this I-D. @techreport{xie-idr-bgpls-sr-vtn-mt-02, number = {draft-xie-idr-bgpls-sr-vtn-mt-02}, type = {Internet-Draft}, institution = {Internet Engineering Task Force}, publisher = {Internet Engineering Task Force}, note = {Work in Progress}, url = {https://datatracker.ietf.org/doc/draft-xie-idr-bgpls-sr-vtn-mt/02/}, author = {Chongfeng Xie and Cong Li and Jie Dong and Zhenbin Li}, title = {{BGP-LS with Multi-topology for Segment Routing based Virtual Transport Networks}}, pagetotal = 10, year = 2021, month = jan, day = 26, abstract = {Enhanced VPN (VPN+) aims to provide enhanced VPN service to support some applications' needs of enhanced isolation and stringent performance requirements. VPN+ requires integration between the overlay VPN and the underlay network. A Virtual Transport Network (VTN) is a virtual underlay network which consists of a customized network topology and a set of network resource allocated from the physical network. A VTN could be used as the underlay to support one or a group of VPN+ services. When Segment Routing is used as the data plane of VTNs, each VTN can be allocated with a group of SIDs to identify the topology and resource attributes of network segments in the VTN. The association between the network topology, the network resource attributes and the SR SIDs may need to be distributed to a centralized network controller. For network scenarios where each VTN can be identified by a unique topology ID, this document describes a mechanism to distribute the information of SR based VTNs using BGP-LS with Multi- Topology.}, }