IT Glossary · Networking

SD-WAN (Software-Defined Wide Area Network)

SD-WAN is a technology that intelligently manages multiple internet connections (ILL, broadband, 4G) across your business locations, automatically routing traffic for performance and cost — replacing expensive MPLS circuits.

Software-Defined WAN (SD-WAN) uses software to control and optimise the routing of network traffic across multiple WAN links. Instead of being locked into a single, expensive MPLS circuit, SD-WAN can aggregate a leased line, broadband, and 4G into a single virtual network. The controller intelligently sends sensitive traffic (VoIP, Zoom) over the best available link in real time, automatically failing over to alternate links if one degrades. For Indian businesses with multiple branches, SD-WAN typically reduces WAN costs by 30–50% while improving cloud application performance.

Edge Devices (CPE): Physical or virtual appliances installed at each branch that connect to the SD-WAN controller and manage local traffic.
Centralised Controller: Cloud-based management platform that provides visibility, policies, and configuration for all sites from one dashboard.
Application-Aware Routing: The system identifies application types (Zoom, SAP, web browsing) and routes each over the optimal WAN link automatically.
Zero-Touch Provisioning: New branches can be configured remotely — ship a device, plug in power and internet, and it joins your SD-WAN automatically.

Related terms: MPLS, Internet Leased Line, WAN Optimisation, SASE, VPN, Network Function Virtualisation

Frequently Asked Questions

How much does SD-WAN cost in India?

SD-WAN for a 5-branch Indian business typically costs ₹80,000–₹2,00,000/month including edge devices, management, and underlying connectivity (ILL/broadband). This is typically 30–50% less than equivalent MPLS. Large deployments (20+ sites) get better per-site pricing.

Can SD-WAN replace MPLS for Indian businesses?

In most cases, yes. SD-WAN with dual ILL links provides better performance for cloud applications than MPLS, at lower cost. Businesses with legacy TDM voice or very strict deterministic QoS requirements may need to maintain some MPLS — but pure IP applications (cloud ERP, Zoom, email) work excellently over SD-WAN.

Explore SD-WAN for your multi-branch network — free WAN assessment with cost savings calculation.