Since the customer prefixes are not known in the VRF of provider, customer traffic can't be natively forwarded through the provider cloud, but needs to be encapsulated by CEs before being sent through the provider cloud. OTP leverages existing LISP encapsulation which: - Allows dynamic multi-point tunneling - Provides instance ID field to optionally support virtualization across WAN (see EVN WAN Extension section) OTP does NOT use LISP control plane (map server/resolver, etc.) instead it uses EIGRP to exchange routes and provide the next-hop, which LISP encapsulation uses to reach remote prefixes. Reference: https://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/ip- routing/whitepaper_C11-730404.html