Cisco CCNA Preparation · lesson 35 of 36 · 25 min
Intent-Based Networking
Intent-Based Networking (IBN) is a network management approach where administrators define the desired outcome (intent) and the system automatically translates that intent into device configurations. Instead of manually configuring each device, you describe what you want the network to do.
Cisco DNA Center (DNAC) is Cisco’s IBN platform — a centralised dashboard for network design, provisioning, policy, and assurance across the entire enterprise network.
DNA Center Four Pillars
SD-Access — Software-Defined Access
SD-Access is Cisco’s campus fabric solution built on DNA Center. It uses VXLAN for the data plane (encapsulates traffic in an overlay), LISP for the control plane (maps endpoint IDs to locations), and ISE for policy enforcement.
SD-Access enables macro-segmentation (VNs — Virtual Networks, equivalent to VRFs) and micro-segmentation (SGTs — Scalable Group Tags) without requiring VLANs to span the entire campus.
DNA Center vs Traditional Management
DNA Center APIs
DNA Center exposes a REST API (northbound) that allows external systems and scripts to interact with the network programmatically. This is central to the CCNA’s network programmability domain.
Common API use cases: query device inventory, retrieve network topology, push configurations, get client health data, trigger workflows.
Knowledge Check — 10 Questions
Cisco DNA Center
What is Intent-Based Networking (IBN)?
- A network that uses only Cisco devices
- A management approach where administrators define desired outcomes and the system translates them to configurations
- A type of VPN
- A wireless networking standard
Answer: A management approach where administrators define desired outcomes and the system translates them to configurations
IBN abstracts network management — you define intent (what you want) and the system handles the how (device configurations). DNA Center is Cisco’s IBN platform.
Which DNA Center pillar handles continuous monitoring and AI-driven issue detection?
- Design
- Policy
- Provisioning
- Assurance
Answer: Assurance
Assurance provides real-time network health monitoring, AI/ML-driven analytics, and proactive issue detection with root cause analysis.
What does SD-Access use for the data plane (encapsulating traffic in the overlay)?
- GRE
- MPLS
- VXLAN
- IPsec
Answer: VXLAN
SD-Access uses VXLAN (Virtual Extensible LAN) for the data plane. VXLAN encapsulates Layer 2 frames in UDP packets, allowing the overlay to span the routed underlay.
What does LISP provide in SD-Access?
- Data plane encapsulation
- Control plane — maps endpoint IDs (MAC/IP) to their location (edge node)
- Policy enforcement
- Wireless management
Answer: Control plane — maps endpoint IDs (MAC/IP) to their location (edge node)
LISP (Locator/ID Separation Protocol) separates endpoint identity from location. It maps endpoint MAC/IP addresses to the edge node where they are connected.
What is PnP (Plug and Play) in DNA Center?
- A wireless configuration protocol
- Zero-touch provisioning — new devices automatically receive their configuration when connected
- A type of ACL
- A routing protocol
Answer: Zero-touch provisioning — new devices automatically receive their configuration when connected
DNA Center PnP allows new devices to be onboarded automatically. The device contacts DNA Center on first boot and receives its full configuration — no manual CLI needed.
What are SGTs in SD-Access?
- Spanning tree groups
- Scalable Group Tags — labels assigned to users/devices for micro-segmentation policy enforcement
- Static gateway tables
- Subnet group tables
Answer: Scalable Group Tags — labels assigned to users/devices for micro-segmentation policy enforcement
SGTs (Scalable Group Tags) are assigned by ISE based on user/device identity. Policy is enforced based on SGT pairs — “Engineering SGT can access Server SGT” — without VLAN-based segmentation.
What type of API does DNA Center expose for external integration?
- SOAP API
- REST API (northbound)
- SNMP only
- CLI API
Answer: REST API (northbound)
DNA Center exposes a northbound REST API that allows scripts, orchestration tools, and ITSM systems to interact with the network programmatically using HTTP methods and JSON.
What is the underlay in SD-Access?
- The VXLAN overlay network
- The physical routed network (all Layer 3 links) that carries the overlay traffic
- The ISE policy engine
- The DNA Center management platform
Answer: The physical routed network (all Layer 3 links) that carries the overlay traffic
The underlay is the physical IP network — all access layer links are routed (Layer 3), typically running OSPF or IS-IS. The VXLAN overlay runs on top of this.
DNA Center’s four pillars are: Design, Policy, Provisioning, and _____.
Answer: Assurance
The four DNA Center pillars: Design (network hierarchy and templates), Policy (business intent as network policy), Provisioning (push configs to devices), Assurance (monitoring and analytics).
What is the main advantage of DNA Center over traditional CLI-based management?
- DNA Center is free
- Centralised intent-based management with automation, assurance, and policy — replacing manual per-device CLI
- DNA Center supports more protocols
- DNA Center works without a network
Answer: Centralised intent-based management with automation, assurance, and policy — replacing manual per-device CLI
DNA Center centralises network management, automates provisioning, enforces policy consistently, and provides AI-driven assurance — dramatically reducing manual effort and human error.
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