I just finished studying the Cisco SD-WAN outline for the CCNP ENCOR 350-401 test and all I can say is…wow. It’s a lot of information. SD-WAN is a bigger part of the ENCOR that I thought it would be. However, I have to admit I’ve drank the Kool-Aid a bit on the future of SD networking. It’s a really interesting area and can drive some very useful and innovated tools to better manage and utilize technologies. In my current work environment, I will probably not have the opportunity to work in a fully SD-WAN infrastructure, and this has made me pretty sad about that fact. However with the rest of the world increasingly adopting cloud-based applications and requiring greater agility in their WAN (Wide Area Network) infrastructures, SD-WAN has emerged as a game-changing technology that offers improved application performance, enhanced security, and simplified operations. Cisco SD-WAN, in particular, is a leading solution in this space, and mastering its concepts and features is critical for CCNP candidates who aspire to be proficient network professionals.

Let’s dive into the key exam topics related to Cisco SD-WAN that should be focused on during the CCNP certification preparation:

1. SD-WAN Architecture: Understanding the architecture of Cisco SD-WAN is fundamental to grasp how the solution operates. Cisco SD-WAN follows a fabric-based architecture, comprising several key components, including:
   • vManage: A central management and orchestration platform that provides a single pane of glass for managing the entire SD-WAN fabric, including device configuration, policies, monitoring, and troubleshooting.
   • vSmart: Intelligent control plane devices that handle the routing and traffic control decisions within the SD-WAN fabric, using policy-based routing, dynamic path selection, and other advanced routing techniques.
   • vEdge: Edge devices that establish VPN connections over the WAN transport and handle the data plane functions, such as traffic encryption, segmentation, and application optimization.
   • vBond: Devices that act as the orchestrator for the initial establishment of secure connections between vEdge devices and vSmart controllers, ensuring secure authentication and authorization.
   • It’s crucial to understand the roles and interactions of these components to design, deploy, and manage a Cisco SD-WAN fabric effectively.
2. Deployment Models: Cisco SD-WAN offers different deployment models that cater to various business requirements and existing network infrastructures. These deployment models include:
   • Overlay Deployment: In this model, Cisco SD-WAN is deployed as an overlay on top of the existing WAN infrastructure, such as MPLS or Internet, allowing for easy adoption without disrupting the underlying network.
   • Hybrid Deployment: This model combines multiple WAN transport options, such as MPLS and Internet, for different applications or locations, based on business policies. Understanding how to configure and manage hybrid deployments is crucial for CCNP candidates.
   • Brownfield Deployment: This model allows businesses to leverage their existing WAN infrastructure and gradually transition to SD-WAN, making it essential to understand the migration process and how to integrate SD-WAN into an existing network.
3. Routing and Traffic Control: Cisco SD-WAN offers advanced routing and traffic control capabilities that are essential for ensuring optimized traffic flow and application performance. Some of the key concepts in this area include:
   • Application-aware Routing: Cisco SD-WAN allows for policy-based routing decisions based on application and user-defined policies, enabling efficient routing of application traffic based on its characteristics, such as performance requirements, security policies, and business priorities.
   • Dynamic Path Selection: Cisco SD-WAN dynamically selects the best path for each application flow based on real-time network conditions, such as link quality, latency, and congestion, ensuring optimal application performance.
   • Policy-based Routing: Cisco SD-WAN allows for defining policies based on application requirements, business priorities, and security policies, and applies these policies to route traffic accordingly, providing granular control over the traffic flow.
   • Quality of Service (QoS): Cisco SD-WAN offers advanced QoS features to prioritize application traffic and ensure reliable performance, such as bandwidth allocation, packet prioritization, and congestion management.
   • WAN Optimization: Cisco SD-WAN provides built-in WAN optimization features, including data compression, deduplication, and TCP optimization, which help optimize WAN bandwidth utilization and improve application performance.
4. Security: Security is a critical aspect of any network infrastructure, and Cisco SD-WAN offers robust security features to protect the SD-WAN fabric and the data flowing over it. Some key security concepts in Cisco SD-WAN include:
   • Encrypted Tunnels: Cisco SD-WAN encrypts all traffic traversing the SD-WAN fabric, ensuring the confidentiality and integrity of data.
   • Secure Boot and Image Verification: Cisco SD-WAN devices are equipped with secure boot capabilities that verify the integrity of the boot image and configuration files, protecting against unauthorized modifications.
   • Authentication and Authorization: Cisco SD-WAN uses a strong authentication and authorization mechanism between vEdge devices and vBond orchestrator, ensuring secure access and control over the SD-WAN fabric.
   • Firewall and Threat Defense: Cisco SD-WAN provides built-in firewall and threat defense capabilities, including stateful firewall, intrusion prevention, and URL filtering, to protect against threats and ensure secure communication within the SD-WAN fabric.
   • Trustworthy Systems: Cisco SD-WAN devices are designed to be trustworthy, with features such as secure manufacturing, secure boot, and secure software updates, ensuring the integrity and security of the devices throughout their lifecycle.
5. Monitoring and Troubleshooting: Efficient monitoring and troubleshooting are critical for maintaining the performance and availability of a network. Cisco SD-WAN provides robust monitoring and troubleshooting features, including:
   • Centralized Monitoring: Cisco SD-WAN offers centralized monitoring and management through vManage, providing real-time visibility into the performance, health, and status of the SD-WAN fabric, as well as detailed analytics and reporting.
   • Event Logging and Alerting: Cisco SD-WAN devices generate event logs and alerts for various system events, which can be used for troubleshooting and proactive monitoring of the SD-WAN fabric.
   • Troubleshooting Tools: Cisco SD-WAN offers various troubleshooting tools, such as packet capture, flow analysis, and CLI troubleshooting commands, to diagnose and resolve network issues quickly.
   • Application Performance Monitoring: Cisco SD-WAN provides application performance monitoring capabilities, allowing network administrators to monitor the performance of specific applications and troubleshoot performance issues.
   • Integration with Network Management Tools: Cisco SD-WAN can integrate with other network management tools, such as SNMP-based network management systems and syslog servers, to enable centralized monitoring and management of the entire network infrastructure.

Conclusion:

Cisco SD-WAN is a powerful technology that offers enhanced application performance, improved security, and simplified network operations. Understanding the key concepts and features of Cisco SD-WAN is crucial in being able to pass the CCNP ENCOR. It’s certainly a lot to digest.