The 'SD-WAN replaces MPLS' narrative was overstated when it started and remains overstated today. SD-WAN replaced MPLS in many places where MPLS was overengineered to begin with. For latency-sensitive, regulated workloads, MPLS is still the right answer.
When SD-WAN is genuinely the right answer
Distributed retail or branch operations with predictable application profiles and modest latency tolerance.
Cloud-first enterprises where the majority of traffic egresses to SaaS and IaaS.
Multi-region operations where local internet break-out and zero-touch provisioning save real operational hours.
When MPLS still wins
Real-time financial trading workloads where deterministic latency is non-negotiable.
Voice-heavy operations where jitter and packet-loss SLAs matter more than throughput.
Regulated environments where the regulator expects (or specifies) a private WAN.
The hybrid that actually works
Most large enterprises end up running SD-WAN over a mix of MPLS, ILL and broadband underlays — using MPLS for the deterministic-latency traffic and ILL/broadband for everything else.
Be explicit about the policy. Application-aware routing is the feature you bought. Use it.
Plan the MPLS exit, but plan it patiently. Three-year retirement plans are normal; one-year plans almost always slip.
This piece is part of the Cylentrix Research Office series. For the deeper reference architecture and engagement model behind it, request a confidential briefing.