Which feature provides the capability for intra-VN traffic filtering and control within the Cisco SD- Access architecture?

MAC ACLs are Layer 2 access control lists that offer basic filtering based on MAC addresses, which is not as scalable or granular for identity-based intra-VN traffic control compared to scalable groups in SD-Access.

Prefix lists are primarily used for filtering IP routing updates based on network prefixes, not for applying identity-based traffic filtering and control within a VN.

Scalable Groups, implemented via Scalable Group Tags (SGTs), are fundamental to Cisco SD-Access for providing identity-based micro-segmentation and access control within a Virtual Network. By assigning SGTs to endpoints based on their role or identity, policies can be applied to precisely control traffic flows between different groups, enabling granular filtering and isolation of intra-VN traffic.

Service policies are generally used for QoS, traffic shaping, or other interface-level traffic management, but they do not provide the identity-based, intra-VN segmentation and filtering capabilities of scalable groups.