Beyond Full Mesh: Solving SD-WAN’s Tunnel Sprawl Problem at Scale

Beyond Full Mesh: Solving SD-WAN’s Tunnel Sprawl Problem at Scale

Enterprise networking has reached the point where growth itself can become the failure mode. A retailer adds regional branches, a bank expands private connectivity, a hospital system pushes more applications closer to users, and suddenly the clean design from an internal review becomes thousands of relationships someone has to operate. Global SD-WAN revenue is projected to rise from $23 billion to $42 billion by 2030, which means the practical question is no longer whether enterprises will keep adopting software-defined wide-area networking, but whether their designs can stay understandable as they grow.

Vijayananda Jayaraman, Senior Technical Leader at Cisco and a judge for the Stevie Awards for Technology Excellence, has spent more than 20 years building routing, multicast, SDN, SD-WAN, and distributed fabric systems across major networking platforms, a background that grounds his view of operational maturity. To understand how teams are moving from connection growth to controllable scale, we spoke with Vijayananda Jayaraman.

The Problem Is Not More Links. It Is More State

“Most teams do not get hurt because one tunnel exists,” Jayaraman says. “They get hurt when every new site creates a new set of state that nobody can reason about during an outage, an upgrade, or a customer escalation.” That is the SD-WAN problem at real scale. The first whiteboard looks harmless. Then the branch count grows, application paths shift, and the team realizes that full mesh connectivity has created an operating model too large for people to inspect manually.

The pressure is visible in branch networking, where SD-WAN rose 27% year over year and branch networking revenue grew 13%. Jayaraman’s work on Mesh Groups in Nuage SD-WAN went directly at that tunnel-sprawl problem. Instead of manually building VPN tunnels between branches, the controller automatically provisioned mesh connectivity inside logical groups, preserving direct paths where needed while keeping inter-group communication governed through policy. In one design review, he recalls sketching branch tunnels until the whiteboard became unreadable, then circling the mess and saying the product had to stop making operators think this way. The answer was grouping, not more manual configuration.

Simplicity Has To Be Designed Into The Control Model

Once a network starts growing in groups rather than individual links, the next problem is management. A design can reduce tunnel count and still fail if every change requires a long chain of device-level actions. Nobody wants to manage that failure scenario at 2 a.m.

The network automation market is projected to grow from $7.88 billion in 2025 to $12.38 billion by 2030, a useful measure of how much enterprises want provisioning and operational work removed from human hands. Jayaraman saw that same need in Junos Fusion Architecture, where he served as Senior Technical Lead for architectural design and end-to-end EVPN implementation inside a single logical switch model. He designed communication between aggregation and satellite devices, worked on ECID handling for multicast groups, integrated EVPN into the Fusion model, and led an engineering team of 10 through reviews, mentorship, and project tracking. “Centralized management is useful only if it removes real work from the operator,” he says. “If the system still forces engineers to touch every device mentally, it is not a simpler network.” The Fusion work helped reduce deployment errors by approximately 80% through a standardized peer-review process and helped customers operate larger switching environments with fewer management touch points.

Data Center Fabrics Taught The Same Lesson Earlier

The SD-WAN scale problem did not appear from nowhere. Data centers hit a related wall first, as virtualization, low-latency applications, and cloud buildouts pushed switching fabrics away from old tiered designs. The data center switch market is expected to grow from $17.93 billion in 2025 to $28.47 billion by 2031. Those numbers help explain why fabric design remains a core infrastructure issue, not a niche protocol debate.

At Juniper, Jayaraman designed and implemented Layer 2 and Layer 3 multicast infrastructure for QFabric, including optimized multicast tables, multicast trees, and filters to reduce latency between data center nodes. He designed BGP update packets to exchange multicast join and leave information between nodes and directors, supported tree construction through directors and interconnects, and addressed duplicate packet risk with filtering in the interconnect layer. When link events forced the system to reprocess all 4k multicast entries, his work optimized the process through cached fabric-link calculations. The design also increased multicast route scale from 4k to 8k.

Efficiency Is Becoming A Design Requirement, Not A Bonus

The same fabric choices now sit inside a harsher physical reality. Data center electricity consumption is projected to reach around 945 TWh by 2030, while data center physical infrastructure revenue reached $10.9 billion in one quarter of 2025. Power, cooling, and floor space are no longer background assumptions. They shape what a network design can afford to become.

That is why Jayaraman’s QFabric work still fits the SDN and SD-WAN conversation. The project was tied to customer TCO gains, including 58% to 76% lower total cost of ownership, 68% to 89% less power, and 90% less floor space. The technical details were multicast tables and fabric links, but the business result was simpler growth. His AI Journal article on AI for social impact gives this point a wider frame because systems supporting healthcare, education, environmental safety, and disaster response still depend on physical infrastructure that must scale without waste. “Efficiency is not only about saving money,” Jayaraman says. “If a design needs too much power, too much space, or too many people to operate, it will eventually limit what the business can deploy.”

The Next SD-WAN Test Is Operational Judgment

The future of SD-WAN will not be decided by whether a vendor can connect branches. That bar has moved. Managed SD-WAN services are projected to grow from $1.3 billion in 2025 to $11.8 billion by 2035, with deployment services representing 48.6% of market revenue in 2025. The demand is shifting toward teams that can deploy, adjust, and govern distributed connectivity without turning every change into a custom engineering exercise.

Jayaraman’s Mesh Groups work is a useful case study because it combined policy-driven grouping with dynamic path steering across MPLS, broadband, and LTE. Traffic could shift when a link degraded, and many deployments could achieve sub-second failover. For telcos and large enterprises, that made SD-WAN more than a connectivity overlay. It became a way to preserve performance while keeping the topology understandable. Nuage received telco orders worth more than $100 million connected to this broader SD-WAN work. As a Beta University Builders of Tomorrow: AI Super Hackathon judge, Jayaraman is evaluating builders whose applications will assume networks can respond quickly to shifting workload behavior. “The next step is judgment inside the network,” he says. “Not magic. Not black boxes. Just better decisions about which paths matter, which groups belong together, and when the system should act before a human has to wake up.”