Top 20 SD-WAN Interview Questions and Answers (2024)
SD-WAN is the most widely deployed solution within the industry and its increasing demand can only be fulfilled by Network Engineers with SD-WAN designing and deployment skills. By any chance, if you being a Network Engineer, are going to appear for such a job role then here are the SD-WAN interview questions and answers that should be at your fingertips. These SD-WAN interview questions are curated by the combined efforts of some of the leading recruiters and our SD-WAN training leaders. SD-WAN is a software-defined networking technology for optimizing and securing Wide Area Networks. It is based on the SDN Technology. SD-WAN simplifies network management and improves application performance. It is also used to decrease cost of WANs by optimizing the best route for data traffic. Let’s move on to see some basic SD-WAN Interview Questions and Answers. Here are the top most asked SD-WAN interview questions that you should be prepared to face in any SD-WAN interview. The traditional Wide Area Networks (WAN) were created using MPLS to connect the large proportions of office traffic that is carried within an intranet’s boundary of the enterprise. However, New Cloud Applications such as Microsoft Office 365, Salesforce and Public Cloud Services such as Amazon Web Services and Azure are transforming traffic patterns. Today, the majority of Enterprise Traffic flows to Public Clouds and the Internet. This has created new requirements for all-in-all security, application performance, Cloud connectivity, WAN Management and operations. SD-WAN provides a brand-new method to manage and operate WAN Infrastructure. It offers a cloud-based solution that offers an efficient, secure and rich service architecture. Salesforce integration services can also make this approach better by facilitating smooth and safe data movement between your on-premise network and Salesforce instances, thereby improving performance and user experience. The key benefits offered by SD-WAN are: Here are a few issues that SD-WAN Solutions overcome: vSmart Controllers form the central part of the solution which establishes policies and connections between branches of the SD-WAN. The central policy engine of Cisco vSmart Controllers offers policies that can be used to alter routing information, access control, segmentation as well as extranets and chaining services. The vBond orchestrator helps with the initial set-up process by ensuring authentication and authorization for all elements in the network. Cisco vBond Orchestrator additionally gives information about how each component communicates with other elements. Cisco vBond orchestrator plays an essential role in the facilitation of Cisco SD-WAN devices which sit behind the Network Address Translation (NAT) to connect to the network. Cisco vManage manages the entire solution. Cisco’s GUI is centralized management and provisioning platform that is available for days 0, 1 and day plus for the whole Cisco SD-WAN system. You can log in on the Cisco vManage dashboard to manage and centrally control the WAN. Cisco vManage gives you the capability to manage every aspect of the WAN from setting up, monitoring, and updating routers, to monitoring and troubleshooting applications on the WAN. SD-WAN connects security and networking together unlike any other technology. SDWAN offer extremely efficient and scalable security that’s simple to deploy, manage, and maintain, helping companies to take advantage of the latest cloud technology with confidence. SD-WAN is built on a zero-trust concept and the multilayer security secures every data stream to ensure security starting from the WAN Edge to Cloud. The entire set of SD-WAN components are able to mutually authenticate one another and all edge devices have to be authorized prior to be allowed access to the network. Each and every packet across the control plane, data plane and management plane that flows through the network is secured with Secure Socket Layer (SSL) and IP Security (IPsec) technologies. The SD-WAN Solution offers distinct capabilities that are integrated to create an extensive IPsec network that spans many branches. Yes, it is true that the SD-WAN solution supports the segmentation of the network. Segmentation allows for secure logical isolation in the SD-WAN network in which each segment is identified as a distinct VPN, and is controlled centrally by access control policies. Some of the Benefits of Segmentation: The latest licensing deals bring customers these advantages: These are some of the most asked basic SD-WAN Interview Questions and Answers. Here are the top most asked advanced level questions and answers – There are multiple advantages of choosing SDN over traditional WAN such as: Here are the Components of SD-WAN: A site is a specific physical area in the Viptela Overlay Network, for example, a branch office or data center or even a campus. The site is identified with a Unicode number, known as the Site-ID. Every Viptela device that is located at a specific site is identified using the same site ID. In a data center each of the vSmart controllers and vEdge routers are set up using the same site ID. Local sites or branch offices generally have one vEdge router. If another one is in place to ensure redundancy, both routers are set up using the same site ID. In the SD-WAN overlay, Virtual Private Networks (VPNs) provide segmentation, just like Virtual Routing and Forwarding instances (VRFs) which many people are familiar with. Each VPN is distinct from the others and has its own forwarding table. A sub-interface or interface is configured specifically under one VPN and can’t be an element of multiple VPNs. Labels are employed to identify the VPN in OMP route attributes as well as in the packet encapsulation process, which determines which VPN a particular packet is part of. The VPN numbers are a 4-byte integer that has values ranging from 0 to 65530. The two VPNs that are by default in the vEdge controllers and devices are VPN 0 and VPN 512. This is the transport VPN. It has interfaces to connect to WAN transports. Secure DTLS/TLS connections to vSmart between vSmart or vBond controllers are established through this VPN. Moreover, the static or default or a dynamic routing protocol needs to be set up within this VPN for it to obtain proper next-hop information, so that it is possible to establish the control plane and IPSec tunnels could connect to distant sites. It is the management VPN. It is responsible for carrying the out-of-band management traffic to and from the Cisco SD-WAN devices. This VPN is not carried across the overlay network. In the case of the hardware-based vEdge appliance, only certain ports are configured by default to be a DHCP client interface and then can be used for ZTP. The following table lists the ports that need to be connected to the network in order for ZTP to function. Some of the common challenges associated with SD-WAN: Some metrics that need to be monitored in an SD-WAN are: TLOC in SD-WAN stands for Transport Locator. It is a crucial concept in Cisco SD-WAN as it represents an attachment point where a Cisco WAN Edge device connects to a WAN transport. It is used for: TLOC consists of 3 components, which are – System IP Address, color, and Encapsulation. SD-WAN uses a combination of features and configurations to prioritize network traffic. It ensures that critical applications get preferred treatment. The key mechanisms used to ensure network traffic prioritization are: This ensures critical applications receive higher priority and optimal performance by assigning traffic classes, marking packets, and intelligently distributing traffic across available WAN links. Application SLA (Service Level Agreement) in SD-WAN defines the performance expectations for specific applications. It outlines the acceptable levels of latency, jitter, and packet loss for these applications. Key elements of an Application SLA are – Some of the benefits of using Application SLA are: By establishing and managing application SLAs, organizations can optimize their SD-WAN network for delivering consistent and reliable application performance. So, these were the top 20 SD-WAN Interview Questions and Answers. Now download 100+ SD-WAN Interview Questions and Answers PDF consisting most asked interview questions with diagrams, examples, and scenario-based solutions curated by SD-WAN experts. For more help, you can always connect with us on Call, WhatsApp, Telegram, Viber, Signal at +91 9821215002, or write to us at [email protected]. We have covered all the most asked SD-WAN Interview questions and answers. Remember this is just a starting point, the depth of your knowledge will be the key to secure your dream SD-WAN job role. Practice delivering these answers confidently and prepare to discuss your past SD-WAN Experience. A few more additional tips to top your next SD-WAN interview – All the best for your Interview.Introduction
About SD-WAN
Basic SD-WAN Interview Questions and Answers
Q1. What is the SD-WAN solution?
Q2. What are the key benefits offered by SD-WAN?
Q3. Which problem can a SD-WAN overcome?
Q4. What are vSmart controllers?
Q5. What are vBond orchetrators?
Q6. What is Cisco vManage?
Q7. Is the Cisco SD-WAN solution secure?
Q8. Does SD-WAN solution support network segmentation and what are the benefits?
Q9. How did viptela SD-WAN help in architectural transformation?
Q10. What benefits do SD-WAN and routing subscription offer?
Advanced SD-WAN Interview Questions and Answers
Q11. Why should one opt for SDN?
Q12. What are the elements of SD-WAN?
Q13. What is site-id?
Q14. What is a Virtual Private Network (VPN)?
Q15. What are the specifications to be met for ZTP?
Q16. What are the common SD-WAN challenges?
Q17. What are the key metrics to monitor in an SD-WAN environment?
Q18. What is TLOC in SD-WAN?
Q19 – How does SD-WAN handle network traffic prioritization?
Q20. Explain the concept of application SLA in SD-WAN.
SD-WAN Interview Questions and Answers PDF
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