Networking is an ever-evolving bowl of alphabet soup: LAN, WAN, MPLS , SD-WAN, SASE, the list goes on and on. The prevalent technologies and approaches in any given time period reflect the contemporary needs and requirements of organizations and their users. One of the biggest debates today is SASE vs SD-WAN, as businesses weigh the trade-off between network optimization and built-in security. Today, this reality includes:
- Complexity: Enterprise networks have evolved to include a wide range of infrastructure, security, and operational tools and systems. Each has its own function and value, but taken together, you have a convoluted ecosystem that’s difficult to manage.
- The cloud: Cloud computing has transformed enterprise networking in countless ways, shifting ownership and responsibility of infrastructure, changing the way applications are delivered and used, and much more.
- Hybrid workforces and remote connectivity: Cloud computing evaporated the network perimeter, which enabled workers to break free from the confines of the office. Hybrid workforces are here to stay and remote connectivity is a necessary requirement.
- Zero-trust security: Increasing sophistication of cyberthreats combined with the imperative to replace or enhance perimeter security tools, given the aforementioned collapse of the network perimeter, has led to zero trust—the security framework built on the principle of “never trust, always verify”—as a best-practice approach.
Enter SD-WAN and SASE as two leading solutions that businesses are evaluating for their network connectivity within this environment.
What is SD-WAN?
Gartner defines SD-WAN solutions as:
“A replacement for traditional WAN routers and are agnostic to WAN transport technologies. SD-WAN provides dynamic, policy-based, application path selection across multiple WAN connections and supports service chaining for additional services such as WAN optimization and firewalls.”
That’s a mouthful packed into a single sentence, so let’s break it down.
Traditional WAN routers are physical hardware appliances that connect geographically dispersed locations using a physical network of private circuits or leased lines and must be manually configured. There are a variety of WAN transport technologies, such as fiber optics, DSL, cable broadband, MPLS, satellite, etc.
SD-WAN, which is short for software-defined wide-area network, enables you to manage the WAN with software (vs. physical appliances) via a dynamic and policy-based approach (vs. individual configurations). The SD-WAN software overlay promises to deliver flexibility, centralized control, and cost savings, enabling better application performance and integrated security. This is the theory, but more about that below.
So, who can benefit from SD-WAN? Examples include organizations that:
- Have many locations or geographically dispersed sites
- Rely heavily on cloud-based applications and services
- Don’t have sufficient networking talent in house to manage configurations
- Are hybrid or have remote workers
- Require high reliability and security
👉 For a deeper dive into how SD-WAN works, its benefits, and implementation best practices, read our SD-WAN Playbook for Enterprises
What is SASE?
Gartner coined the term SASE (short for secure access service edge), which they define as delivering “converged network and security as a service capabilities, including SD-WAN, SWG, CASB, NGFW and zero trust network access (ZTNA). SASE supports branch office, remote worker and on-premises secure access use cases. SASE is primarily delivered as a service and enables zero trust access based on the identity of the device or entity, combined with real-time context and security and compliance policies.”
You’ll notice that in this definition of SASE, SD-WAN is just one type of functionality that combines with cloud-native security services into a single, integrated cloud service. Where SD-WAN is the means of delivering networking and security for distributed environments, SASE is the broader, integrated architecture.
The core components of the SASE architecture include:
- SD-WAN: Optimizes network connectivity
- Secure web gateway (SWG): Performs web content filtering and related policy enforcement
- Cloud access security broker (CASB): Acts as a gatekeeper for cloud applications and enforces security policies
- Firewall-as-a-service (FWaaS) or next-generation firewall (NGFW): Cloud-based firewall that provides perimeter protection.
- Zero trust network access (ZTNA): Grants access to specific resources on a per-session basis after user/device verification
- Unified threat management (UTM): Intrusion detection/prevention system (IDS/IPS) that filters malicious content/malware, and enforces security policies
Because SASE centralizes policy management, it ensures consistent security across all users and devices. By integrating multiple security functions, it offers a unified security framework—with simplified management—to enhance an organization’s security posture. SASE brings network and security services closer to the “edge” (hence the name), directing traffic to the nearest cloud-based point of presence (PoP) to perform security and network functions. This avoids the need to backhaul traffic through a central data center.
Vendor access management is another benefit of SASE. Many security incidents start from a third party’s access to the organization’s system; SASE prevents this by only allowing the vendor access to the system(s) they require access to.
Who benefits from SASE? Examples include:
- Hybrid and remote work
- Multi-site, geographically dispersed locations
- Cloud and digital initiatives
- IoT and industrial IoT (IIoT) security
- Global connectivity
There is a lot overlap with the list of organizations that benefit from SD-WAN, so let’s dig a little deeper into the differences.
This video by an industry expert provides a quick overview of SD-WAN and SASE:
SASE vs SD-WAN side-by-side: Key differences
| SD-WAN | SASE | |
| Primary focus | Improve network performance | Provide a holistic approach to networking and security |
| Deployment architecture | Traditional hub-and-spoke using on-premises applications and a centralized control plane | Cloud-native distributed architecture with global PoPs |
| Security features | Offers basic features and often requires separate solutions for comprehensive security | Natively integrates comprehensive security functions into a unified service |
| Policy enforcement | Primarily enforces network routing policies | Enforces consistent and dynamic security policies across all users, devices, and applications, regardless of location |
| Management complexity | Can be resource-intensive to manage, especially in multi-cloud environments, and requires management of separate security tools | Consolidates network and security functions into one platform/interface for streamlined management |
| Cost | Lower, particularly if you have existing networking appliances, but you also need to factor in the cost of third-party security appliances/tools | Higher because it bundles multiple security services together with SD-WAN, but reduces the need for capital-intensive hardware |
| Best suited for | Organizations primarily concerned with optimizing network traffic between fixed locations (e.g., branch offices and a central data center) | Organizations with a distributed, hybrid workforce and extensive use of cloud applications who want simplified, end-to-end security |
Will SD-WAN meet my needs or do I need to add SASE?
There is no one-size-fits all answer. Here are key factors to consider when choosing between SD-WAN on its own or a full SASE + SD-WAN solution for your organization.
What is your organizational size and structure?
If you are a small or mid-sized business with primarily on-premises infrastructure, SD-WAN might be sufficient. SASE, on the other hand, is better suited for larger organizations with a large hybrid or remote workforce and a significant cloud presence.
What are your network needs and architecture?
If your primary focus is on optimizing traffic and connectivity and have a significant investment in networking gear, SD-WAN improves deployment flexibility. If, however, your priority is to secure remote users across a geographically dispersed workforce relying heavily on cloud applications, SASE is likely the better option.
What are your security requirements?
SD-WAN does offers enhanced security, but it’s a secondary feature that often requires additional security solutions. SASE, on the other hand, is built with a security-first approach, making it the right choice where robust security, particularly zero trust, is a must.
Do you prioritize control or simplified management?
SD-WAN can provide more control over your infrastructure, but can increase complexity. As a cloud-delivered solution, SASE simplifies management but offers somewhat less control.
What are your scalability needs?
SASE easily scales and adapts to new technologies. While SD-WAN can scale, it may require significant additional investment in hardware and infrastructure.
What in-house expertise do you have?
If you have an IT team that understands traditional networking (e.g., routing, traffic management, network architecture, WAN technologies like MPLS, etc.) SD-WAN can provide a more comfortable transition, though configuration complexity can be time-consuming. SASE requires an integrated skill set—networking, security, and cloud environments—and may require specialists from those different teams to collaborate. Depending on your in-house resources, you may want to consider a managed SASE or SD-WAN solution (more on that below).
What are your principal cost considerations?
If you have already invested heavily in compatible on-premises security appliances, SD-WAN might be more cost-effective in the short term. But if your top priority is securing remote users, SASE can be the more cost-effective choice as it natively handles security for users anywhere. Furthermore, SASE can reduce the total cost of ownership over time by simplifying management, reducing hardware needs, and offering a scalable, cloud-native platform.
Why managed SASE and SD-WAN solutions matter
There’s no doubt that both SD-WAN and SASE offer significant benefits. But implementing them correctly, and managing them on an ongoing basis, can be tricky. Here are a few very common challenges:
- Integration with legacy systems in a complex network infrastructure can be difficult and lead to interoperability problems.
- Managing connections to diverse cloud services requires cloud-specific expertise and careful planning.
- Reliable performance with SD-WAN depends on the performance of underlying internet connections, and underlay provisioning can be challenging.
- SASE requires a deep understanding of both networking and security, often beyond the capabilities of a typical IT team.
- SASE’s centralized architecture can introduce latency, and if it’s not designed correctly, it may not provide optimal network performance.
- Selecting vendors and managing those relationships can be overwhelming and add to the complexity of a DIY SD-WAN or SASE project.
This is just a small sample; there are a lot of other potential hurdles that can stand in the way of successful SASE and SD-WAN deployments. That’s where managed services come in. A managed SD-WAN or managed SASE service lets you tap into expertise that you may not have in house to design an effective solution. And because the partner manages it all for you with ongoing monitoring and support, your team is freed up to focus on other activities.
Real-world SASE and SD-WAN applications and success stories
BCM One’s Managed SD-WAN, with optional SASE, pairs industry-leading SD-WAN technology with BCM One’s hands-on expertise for a complete, business-ready solution.
“Based on what clients tell us, what sets BCM One’s Managed SD-WAN apart comes down to three key things. First, we manage all the different providers—including SLAs, support, and billing—on one invoice and with one point of contact. Second, proactive 24×7 monitoring is built in, providing fast problem-solving and peace of mind. And finally, the overlay of our Pure IP Enterprise Voice solutions enable them to fully align communications and connectivity.”
– Michael Hawkins, Director of Solutions Engineering at BCM One
Here’s how BCM One’s Managed SD-WAN, along with Managed Connectivity, helped a sports marketing company revamp and modernize their connectivity:
- Problem: The company was experiencing outages, issue reporting was terrible, and monitoring and management were non-existent. Making matters worse, their SD-WAN setup was obsolete and did not adhere to modern best practices from an optimization standpoint.
- Solution: BCM One worked with them to redesign the entire network infrastructure, incorporating our Managed Connectivity solution for all of their ten locations nationwide. We designed dual network redundancy so that there was redundancy within every site and geo-redundancy across the different locations. We also completely redesigned SD-WAN for their network.
- Benefits: It’s all now fully managed with monitor, notify, and restore services—though with zero outages to date they haven’t needed to use our monitoring suite.
Contact us to learn more about BCM One’s Managed SD-WAN or to consult one of our experts for a personalized strategy.
Frequently asked questions
Can you deploy SD-WAN without SASE?
SD-WAN can be implemented on its own, but adding SASE integrates security capabilities that many organizations need to meet comprehensive cybersecurity requirements.
Does SASE replace SD-WAN?
SASE does not replace SD-WAN; rather it incorporates and builds on SD-WAN by integrating its core networking capabilities with cloud-native security services to create a unified, cloud solution.
How is traffic routed and optimized in a managed SASE architecture?
A managed SASE architecture uses SD-WAN to intelligently route traffic over the best available path based on real-time performance metrics to ensure an optimal user experience.
How does SASE improve regulatory compliance and data protection?
SASE incorporates encryption, consistent policy enforcement, zero trust network access (ZTNA) and other controls required by most regulations and standards.
Can managed SD-WAN integrate with my existing network infrastructure and cloud services?
Yes, managed SD-WAN solutions are designed specifically to integrate with existing network infrastructure, whether that’s MPLS circuits, broadband, or other connections, and provides optimized connectivity to cloud services.
