What are the ACI underlying protocols?

Cisco ACI uses the following protocols for the control plane: 1- LLDP: for fabric discovery. 2- DHCP: for fabric nodes IP settings assignment from APIC. 3- IS-IS: for VTEPs infra network reachability. 4- COOP: for endpoints reachability information from the leaf to the spine switches. 5- MP-BGP: for external route redistribution inside the ACI fabric. 6- IFM: for policy communication. 7- NTP: for time sync in the fabric. For Data plane; Cisco ACI uses iVXLAN encapsulation. iVXLAN uses a custom UDP destination port, 48879, instead of the standard VXLAN UDP port 4789.

Cisco ACI Underlying Protocols (Data, Control & Mgmt Plane)

February 2, 2025 / By Salman Alhiary

Cisco ACI redefines how we design, deploy, and manage data center networks. The ACI underlying protocols interplay the Data, Control, and Management plane.

In this video, I unravel the Cisco ACI underlying protocols.

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Summary

The Underlay network represents the hardware infrastructure.
The Overlay network represents the virtual network interconnecting the end devices.
ACI Data Plane: iVXLAN encapsulated packets.
ACI Control Plane: LLDP, DHCP, IS-IS, COOP, MP-BGP, IFM & NTP.
ACI Management Plane: GUI, CLI & REST API (INB vs. OOB).