Which ISP technology can be implemented as a service when designing a topology to perform extranet connectivity via multitenant segmentation from within a corporate intranet?

Cisco Easy VPN is a client-based remote access VPN solution designed for individual users or small sites, not for ISP-grade multitenant extranet segmentation.

GRE over IPsec creates static encrypted point-to-point tunnels between two endpoints and does not natively support multitenant segmentation across a shared ISP infrastructure.

MPLS L3VPN uses VRFs on provider edge routers to maintain logically separate routing tables per customer, enabling multitenant segmentation at scale; a corporate intranet can extend extranet connectivity to partners or tenants through the same MPLS infrastructure without requiring separate physical links, which is a native ISP service offering.

VTI (Virtual Tunnel Interface) simplifies IPsec configuration for point-to-point tunnels but is not an ISP service technology and provides no multitenant segmentation capability.

VPNaaS (VPN as a Service) is not a recognized standard ISP technology in the context of Cisco enterprise networking certifications and does not specifically describe multitenant MPLS-based segmentation.