Multidestination Packet Forwarding Approach

C.

Cisco Application Centric Infrastructure (ACI) is a software-defined networking (SDN) solution that uses a policy-based approach to automate the configuration and management of data center networks. One of the key features of ACI is the ability to achieve multidestination packet forwarding between leaf switches in the same fabric using VXLAN (Virtual eXtensible LAN) technology.

VXLAN is a network virtualization technology that enables the creation of logical layer 2 networks over a layer 3 infrastructure. VXLAN encapsulates layer 2 Ethernet frames in IP packets with a VXLAN header. The VXLAN header includes a VXLAN Network Identifier (VNI) that identifies the VXLAN segment, and a VXLAN Tunnel End Point (VTEP) that identifies the source or destination of the packet.

To achieve multidestination packet forwarding between leaf switches in the same fabric, Cisco ACI uses the approach of mapping VXLAN VNI to the multicast group. When a packet is sent from a leaf switch to multiple destination leaf switches, the source leaf switch encapsulates the packet in a VXLAN header with a VNI that corresponds to the VXLAN segment that the packet belongs to. The source leaf switch then sends the packet to the multicast group that corresponds to the VNI.

Each leaf switch that is a member of the multicast group receives the packet and decapsulates it to extract the original Ethernet frame. The leaf switch then forwards the Ethernet frame to the appropriate endpoint based on its forwarding table.

Therefore, the correct answer to the question is C. Map VXLAN VNI to the multicast group. Option A (Map VXLAN VTEP to the multicast group) is not correct because VXLAN VTEP is used to identify the source or destination of the packet, not the multicast group. Option B (Map VXLAN to PIM-SM protocol) and Option D (Map VXLAN to PIM-DM protocol) are not correct because PIM (Protocol Independent Multicast) is not used in ACI to achieve multidestination packet forwarding between leaf switches.