What is SD-WAN security? | Definition from TechTarget

What is SD-WAN security?

SD-WAN security refers to the practices, protocols and technologies protecting data and resources transmitted across software-defined wide area network infrastructure.

SD-WAN is designed for internetwork communication, or communication between two separate networks. It is the technological successor to the long-established multiprotocol label switching (MPLS), an ideal networking protocol for intranetwork communication, or communication between two applications or systems within a data center or private network.

However, MPLS does not handle communication between a private network and cloud service providers (CSPs) such as Amazon Web Services. Here, SD-WAN steps in, simplifying the management and operation of a wide area network by decoupling the network hardware from its control mechanism.

The challenges of SD-WAN security

SD-WAN must securely manage communications between the private and the public cloud. It routes traffic based on application requirements, network conditions, regulatory compliance concerns and business policies using prioritization and centralized management.

The widely distributed nature of the network and its connection to the open internet create the following challenges for SD-WAN security:

• Encryption and authentication. When moving data between public and private clouds, encryption is mandatory. However, this limits visibility into encrypted traffic, making it difficult to detect and prevent more advanced threats. Security experts seek to strike a balance between encryption and traffic monitoring.
• Cloud protection. To protect customer traffic from cloud-specific threats, CSPs have unique security services — in particular, cloud access security brokers (CASBs) and cloud security posture management.
• Endpoint protection. Remote users, branch offices, remote devices and internet of things devices all present a greater challenge than a networked PC inside a private network. Antivirus software, endpoint detection and response, and mobile device management systems offer endpoint security.
• Scalability and performance. SD-WAN performs encryption and decryption in real time, but large language models and increasing deployments require greater computational resources. Security platforms and equipment must handle increasing volumes of data without compromising computing or network performance.
• Visibility and control. Many enterprises deploy a multi-cloud system, dynamically routing traffic across many paths and clouds. Maintaining visibility in these networks is both crucial and difficult due to the sheer volume of data being moved. It requires mature and robust monitoring and management tools.
• Threat detection and response. SD-WAN environments face malware, ransomware and advanced persistent threats. Behavior-based analytics, threat intelligence feeds and automated response mechanisms offer advanced threat detection capabilities.
• Compliance and governance. Compliance with regulatory requirements — such as the General Data Protection Regulation, Health Insurance Portability and Accountability Act and Payment Card Industry Data Security Standard — ensures organizations secure the data flowing from private centers through the open web to the CSP.

Benefits of SD-WAN security

There are several benefits to using SD-WAN security, many of which don’t exist in an MPLS environment. They include the following:

• Secure connectivity. SD-WAN supports several secure connectivity protocols to protect in-transit data, including Internet Protocol Security, virtual private networks and Transport Layer Security encryption. Meanwhile, CASBs offer cloud service connectivity protection.
• Centralized control. SD-WAN centralizes network management and security policies, providing administrators with a single interface to multiple networks, systems and clouds. Centralized control simplifies security management and distribution of fixes while reducing the risk of error.
• Load balancing. SD-WAN platforms offer dynamic traffic routing and steering based on security policies and threat intelligence. This enables organizations to segment traffic and direct sensitive data through known secure channels to minimize its exposure.
• Automated threat response. SD-WAN platforms can be configured for incident response automation, blocking suspicious or malicious traffic, isolating compromised devices or redirecting traffic to security inspection services. Automation avoids waiting for human intervention and provides immediate response to threat detection.
• Third-party integration. SD-WAN vendors offer integration with third-party security services, such as firewalls, intrusion prevention systems and secure web gateways.

Features of SD-WAN security

The benefits mentioned above result from SD-WAN security’s unique features. Among its key aspects are the following:

• Authentication. Only approved users can access the network. This means that not only passwords, but also multifactor authentication and digital certificates verify the identity of users and devices connecting to the SD-WAN network.
• Fine-grained access control. SD-WAN allows organizations to define policies based on user roles, applications and other parameters, affording more precise and detailed control over access. Next-generation firewalls and access control lists help enforce these policies and restrict unauthorized access to sensitive resources.
• Network segmentation. By dividing the SD-WAN infrastructure into zones based on factors such as user roles, departments or security requirements, network segmentation isolates zones from each other and prevents the free movement of security intruders.

SD-WAN security best practices

With its features and benefits properly applied, SD-WAN security can meet the morphing challenges of data transmission and its interception. Here’s how:

• Threat protection. Start by deploying next-generation firewalls, intrusion prevention systems, antivirus/antimalware software, and other threat prevention technologies at strategic points within the SD-WAN architecture. Use predefined security policies and threat intelligence feeds when configuring them.
• Encryption. Encrypt traffic across the SD-WAN — particularly data traveling from the network to the cloud. Use strong encryption protocols such as Advanced Encryption Standard and secure key management practices to protect data in transit.
• Continuous monitoring. Monitor and log all network activity to detect anomalies and identify potential security issues. Use one of the many security information and event management tools to review and analyze security logs.
• Well-defined security policies. Set security policies that comport with your organization’s regulatory requirements and risk tolerance. Establish rules for verification, threat detection and response, traffic segmentation, application control, encryption and access control.
• Segmentation. Use network segmentation to isolate more sensitive data and assets from less secure parts of the network, balancing encryption and security. Sensitive data receives maximum protection, while less vital data needs little or no encryption, freeing resources.
• Secure cloud connectivity. Offer secure connectivity from data centers, branch offices and other remote locations to cloud service providers through features such as direct internet access and cloud on-ramp services. Implement encryption, authentication and traffic management to maximize security and performance.
• Patch management. SD-WAN firmware, software and other components are constantly updated to address newly found vulnerabilities. Establishing a formal patch management process to test, deploy and verify patches across your network without disrupting business operations is essential.