SD-WAN vs MPLS in 2018: Where Are We Now?

November 2018 • 7 min read

Introduction

In 2018 the networking world buzzes with discussions about SD-WAN. Vendors flood the market, and enterprises weigh the pros and cons of moving away from traditional MPLS circuits. But is SD-WAN truly ready to displace MPLS at scale? And in what use cases does it make sense?

The Legacy of MPLS

MPLS has long been the gold standard for enterprise WAN. It offers predictable latency, tight SLAs, and traffic engineering. Carriers bundle it with managed services, making it attractive to businesses lacking in-house WAN expertise. However, MPLS also comes with high costs, inflexible provisioning, and lengthy deployment timelines—issues that motivate a shift.

The SD-WAN Proposition

Software-Defined WAN introduces agility to the network edge. It leverages broadband, LTE, and even satellite to create virtual overlays. Policies steer traffic based on performance, application type, or security needs. Centralized orchestration replaces CLI-based provisioning. SD-WAN promises better economics and faster rollouts—but these benefits depend on proper implementation.

2018 State of the Market

By late 2018, we observe large-scale SD-WAN adoption across verticals. Financial institutions pilot it in branches. Retail chains use it for point-of-sale systems. Multinational corporations embrace hybrid WANs—MPLS for critical paths, Internet for non-sensitive apps. Gartner predicts over 40% of enterprises will evaluate SD-WAN by year-end.

Security Becomes a Key Differentiator

Early SD-WAN solutions focus on connectivity, not security. In 2018, vendors shift to embed firewalls, segmentation, and even cloud-based ZTNA. Integration with cloud security platforms like Zscaler or Palo Alto Prisma becomes a market expectation. SD-WAN is no longer just a routing solution—it’s part of the broader secure edge architecture.

Performance and SLA Realities

Critics point out that public Internet lacks the deterministic quality of MPLS. This holds true, especially for real-time apps like voice and video. However, SD-WAN mitigates this through path monitoring, FEC, and dynamic failover. The key lies in deploying diverse transport types and validating the last-mile performance.

Cost Optimization—But With Caveats

SD-WAN reduces cost per Mbps by enabling use of commodity broadband. Enterprises escape expensive MPLS lock-ins. Yet, total cost of ownership depends on licensing, hardware refreshes, and additional security layers. Some enterprises overestimate savings by ignoring these factors. Careful financial modeling is required before transition.

Operational Models Are Shifting

SD-WAN demands new skills. Network teams now manage overlays, policies, and application-based routing. Tools shift from CLI to GUI and API. Enterprises invest in retraining staff or outsourcing SD-WAN management to MSPs. Operations center workflows evolve as visibility moves from routers to orchestration portals.

Cloud and SaaS Traffic Patterns

Traditional WAN designs backhaul Internet traffic to data centers for inspection. SD-WAN enables local breakout for services like Microsoft 365, Salesforce, and AWS. This reduces latency and offloads data center firewalls. As cloud adoption rises, SD-WAN becomes the de facto method for optimizing user experience.

SD-WAN vs MPLS: Complementary or Competing?

For most enterprises in 2018, SD-WAN does not fully replace MPLS. Instead, they coexist. Branches run hybrid WANs. MPLS provides SLA-backed backbone, SD-WAN provides agility and cost savings. The future points to more Internet-first WANs—but MPLS remains relevant where predictability matters most.

What to Watch Going Forward

• SD-WAN convergence with SASE and cloud security
• 5G and edge computing extending SD-WAN use cases
• Carrier-managed SD-WAN offerings increasing in popularity
• Open standards and interoperability between SD-WAN vendors
• Analytics and AI driving performance optimization

Conclusion

In 2018, SD-WAN transitions from hype to maturity. Enterprises see real value—but also encounter real complexity. MPLS still holds its place for mission-critical paths, but SD-WAN rewrites how branch connectivity scales. Going forward, success belongs to those who balance flexibility, security, and performance.

Eduardo Wnorowski is a network infrastructure consultant and Director.
With over 23 years of experience in IT and consulting, he helps organizations maintain stable and secure environments through proactive auditing, optimization, and strategic guidance.
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MPLS VPN Deployment in Enterprise Branch Connectivity

 May 2010    |   Reading time: 10 min

As enterprises expand geographically, legacy point-to-point WAN links are giving way to more scalable and manageable solutions. MPLS Layer 3 VPNs are now a mainstream option for connecting multiple branches through a service provider backbone while maintaining routing segmentation and QoS guarantees.

Why MPLS VPN?

MPLS VPN allows enterprises to build private networks over shared infrastructure. Each branch receives a virtual routing and forwarding (VRF) instance, isolating customer traffic. This simplifies policy enforcement, reduces routing complexity, and enhances application performance with QoS features.

Architecture Overview

The core design includes Customer Edge (CE) routers at branch locations and Provider Edge (PE) routers at the carrier’s edge. The enterprise controls the CE router while the service provider manages the MPLS backbone and PE-CE routing protocol relationships, usually via BGP or static routes.

Sample Configuration – BGP PE-CE

router bgp 65001
 neighbor 192.0.2.1 remote-as 64512
 network 10.10.10.0 mask 255.255.255.0
!
interface GigabitEthernet0/1
 ip address 10.10.10.1 255.255.255.0
!
ip route 0.0.0.0 0.0.0.0 192.0.2.1
  

Routing Control and Security

Route distinguishers and route targets are the key mechanisms for separating and importing/exporting routes in MPLS VPNs. The service provider assigns RDs, while the enterprise defines RT import/export policies to control what prefixes are visible across branches. This prevents route leakage and enforces segmentation.

QoS and SLA Considerations

MPLS VPNs support differentiated services (DiffServ) models. Enterprise branches can classify and mark packets (e.g., voice, video, data) before they enter the provider cloud. The service provider maps those to corresponding classes and honors service-level agreements. This ensures predictable latency and packet delivery for business-critical apps.

Monitoring and Troubleshooting

show ip bgp vpnv4 all
show ip route vrf 
ping vrf  
traceroute vrf  
  

Monitoring VPN routes and path reachability is critical for ongoing operations. Use the BGP VPNv4 table to view propagated prefixes and verify VRF-specific routes using standard diagnostics with the VRF keyword.

Conclusion

MPLS Layer 3 VPN is a proven, mature technology for scalable branch connectivity. It simplifies WAN management, enforces routing control, and supports QoS across diverse applications. Enterprises deploying MPLS VPN today gain a future-proofed backbone with the flexibility to evolve toward hybrid WAN and cloud-ready architectures.

Eduardo Wnorowski is a network infrastructure consultant and technologist.
With over 15 years of experience in IT and consulting, he brings deep expertise in networking, security, infrastructure, and transformation.
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