SD-WAN vs MPLS for Multi-Site Businesses: Cost, Performance & Security

• 27 June, 2026
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For Indian enterprises with multiple sites, the WAN connectivity decision comes down to a single question: MPLS or SD-WAN? The answer isn’t as simple as “SD-WAN is cheaper” or “MPLS is more reliable.” Both technologies have evolved significantly, and the right choice depends on your specific requirements for uptime, security, application performance, and budget.

This comparison gives you the practical trade-offs based on real deployments across Indian manufacturing, BFSI, logistics, and retail sectors — from 5-site chains to 200+ site enterprises.

What Each Technology Actually Delivers

MPLS (Multi-Protocol Label Switching)

MPLS is a private WAN technology. Your traffic travels over your service provider’s dedicated infrastructure, isolated from the public internet. It’s been the gold standard for enterprise WAN for two decades for good reasons:

• Deterministic performance: Consistent latency, jitter, and packet loss — no best-effort variability even during peak hours
• Built-in SLA: Service providers guarantee 99.5-99.9% uptime with financial penalties for breaches
• No encryption overhead: Traffic is already on a private network — no need for IPsec VPN on every link
• Traffic engineering: QoS markings are honoured end-to-end across the provider’s network

SD-WAN (Software-Defined WAN)

SD-WAN overlays intelligent routing on top of any WAN transport — MPLS, broadband, 4G/5G, or satellite. The FortiGate at each site makes real-time routing decisions based on application requirements and link quality. This is where the FortiGate SD-WAN capability truly shines for Indian multi-site deployments:

• Transport independence: Uses any combination of MPLS, broadband, LTE/5G simultaneously — you’re not locked into one provider
• Active-active multipathing: Traffic load-balanced across all links; sub-second failover on link failure without dropped sessions
• Application-aware routing: VoIP takes the low-latency path; bulk transfers take the high-throughput path; critical apps get priority
• Built-in security: IPsec encryption across all links; NGFW features integrated at the edge — no separate firewall required
• Centralised management: FortiManager configures all sites from a single pane of glass, with policy changes pushed in seconds

Cost Comparison (Indian Market 2026)

Typical 20-site deployment (3-year TCO):

• MPLS-only (50 Mbps per site): ₹1.8-2.4 crore total (₹75,000-1,00,000 per site per month)
• SD-WAN with broadband + 4G backup (dual 50 Mbps links per site): ₹60-80 lakh total (₹25,000-35,000 per site per month)
• Hybrid (SD-WAN over MPLS + broadband backup): ₹1.2-1.6 crore total — best performance but still 30-40% savings vs MPLS-only

Savings: 55-70% when replacing MPLS with SD-WAN over broadband. 30-40% when using hybrid.

Performance Comparison

Security Considerations

MPLS: MPLS is a private network, but it’s not encrypted by default. Traffic traversing the provider’s infrastructure is isolated from the internet, but the provider’s staff and infrastructure have access. For compliance purposes (DPDP Act, CERT-In), MPLS alone does not provide data-in-transit encryption. You still need IPsec or TLS for sensitive data — something many enterprises overlook when they assume “private network = secure.”

SD-WAN: FortiGate SD-WAN encrypts ALL traffic with IPsec by default — regardless of the underlying transport. Traffic over broadband is encrypted end-to-end. For the hybrid scenario, you can choose to exempt MPLS traffic from encryption for performance, but most compliance frameworks prefer encryption everywhere.

Additional SD-WAN security advantages:

• NGFW features at every branch edge (IPS, antivirus, web filtering, application control) — no need for a separate firewall at each site
• Centralised security policy management via FortiManager — consistent rules across all sites, updated in minutes
• ZTNA integration for remote access — branch FortiGates can act as ZTNA gateways
• FortiGuard threat intelligence feeds block known C2 and malware domains at every branch edge

When to Choose Which

Choose MPLS (or MPLS + SD-WAN hybrid) when:

• Your applications are latency-sensitive (VoIP, video conferencing, real-time SCADA/ICS)
• You have regulatory requirements for private network isolation (BFSI, government classified networks)
• You DON’T have internet-grade broadband at remote sites (some rural and industrial areas still lack reliable broadband)
• Your existing MPLS contracts are in the middle of their term and buyout costs are prohibitive
• You need deterministic performance guarantees backed by service provider SLAs

Choose SD-WAN (broadband-based) when:

• You’re opening new sites frequently and need rapid connectivity without 6-12 week MPLS lead times
• Your primary goal is WAN cost reduction (55-65% savings over MPLS — this is real, not theoretical)
• You have reliable broadband at most sites (check actual ISP performance, not advertised speeds)
• You need more bandwidth than MPLS can cost-effectively provide (100+ Mbps per site becomes exponentially expensive with MPLS)
• You want consistent security policies across all sites without deploying separate firewalls
• Your applications are cloud-based (SaaS, IaaS) and need direct internet access rather than hairpinning through a central data centre

The P J Networks Recommendation

For most Indian enterprises with 10-100 sites, the optimal architecture is hybrid: SD-WAN over MPLS as the primary link + broadband or 4G/5G as backup. You keep MPLS performance for critical apps, gain active-active failover, reduce WAN cost by 30-40%, and get integrated security at every branch.

For enterprises with 100+ sites or those in highly regulated sectors, MPLS as the primary transport with SD-WAN overlay for intelligent routing and failover is the preferred architecture. The SD-WAN layer gives you application-aware routing and sub-second failover while MPLS provides the deterministic backbone.

For smaller deployments (5-20 sites) where cost is the primary driver, SD-WAN over dual broadband links delivers 99.99% uptime at 60-70% lower cost than MPLS.

Next Steps

P J Networks has designed and deployed SD-WAN architectures for Indian enterprises from 5 to 200+ sites. We work with FortiGate SD-WAN, FortiManager, and FortiAnalyzer to deliver end-to-end WAN solutions with integrated security and compliance.

Contact us for a WAN architecture assessment — we’ll analyse your current connectivity, application requirements, and budget, and deliver a recommended architecture with a full cost comparison and phased migration plan.

P J Networks is a Fortinet MSSP partner with deep expertise in SD-WAN and MPLS. We design, deploy, and manage WAN architectures for Indian enterprises across all major sectors.