Calnex Solutions and VIAVI Solutions have announced a joint push to advance testing for Open RAN deployments and broader network infrastructure, extending a test-and-measurement collaboration that now targets the coordination, timing and interoperability challenges operators face as they disaggregate their radio access networks.

The announcement, reported by The Fast Mode, positions the two test vendors around a common problem: Open RAN replaces tightly integrated single-vendor stacks with multi-vendor combinations of radios, baseband units and RAN intelligent controllers, and each interface in that chain needs to be validated before and after deployment.

Neither company disclosed contract values, deployment figures or named operator customers in the announcement.

What does the partnership cover?

Calnex brings its specialty in network synchronization and timing test — the measurement of clock accuracy, phase alignment and SyncE/PTP behaviour that 5G radio coordination depends on. VIAVI contributes its broader portfolio in RAN testing, fiber and transport validation, and service assurance.

Together, the vendors say, the combined toolset gives operators and equipment makers a way to check Open RAN components against timing and performance requirements across the full network path, from radio site to transport to core.

The joint offer addresses several practical needs:

• Timing and synchronization validation for Open RAN fronthaul and midhaul links
• Conformance and interoperability checks across multi-vendor RAN equipment
• Test coverage for transport infrastructure that carries Open RAN traffic
• Support for operators integrating radios and baseband units from different suppliers

Why testing matters for Open RAN

Open RAN's core promise is vendor choice: operators can mix radios from one supplier with baseband software from another and orchestrate them through open interfaces defined by the O-RAN Alliance. That architectural freedom carries a testing burden that traditional, single-vendor RAN never imposed.

In an integrated RAN, the vendor tests its own closed system end to end. In a disaggregated one, an operator combining components from multiple vendors effectively becomes a systems integrator and needs independent verification that the pieces interoperate, stay synchronized and meet throughput and latency targets under real traffic.

Timing is the sharpest of those requirements. 5G features such as carrier aggregation and coordinated transmission between sites depend on tight phase synchronization across the network. When fronthaul is virtualized and carried over standard Ethernet, validating that synchronization becomes a discrete test discipline — the one Calnex has built its business around.

Test and measurement vendors have been consolidating their Open RAN positions for several years as operators in Europe, Asia and North America moved from Open RAN trials to commercial deployments. Partnerships between specialists are one way for smaller vendors to match the breadth that Tier 1 test houses offer.

Commercial reality versus the Open RAN pitch

The announcement is a vendor collaboration, not an operator deployment, and it comes without named customers or revenue figures — a common pattern in the test-and-measurement segment, where tooling deals are rarely publicized.

The commercial context is nonetheless real. Operators running Open RAN networks — and vendors selling into O-RAN Alliance compliance regimes — need certified, repeatable test processes before they can scale multi-vendor RAN beyond pilots. Test tooling is a precondition for that scaling, not a consequence of it, which is why test vendors keep investing in Open RAN portfolios even where operator rollout volumes have lagged earlier forecasts.

The partnership also reflects where Open RAN testing demand actually sits today: not only in radio-layer performance but in the unglamorous plumbing — synchronization, transport, fronthaul timing — where integration failures most often surface.

What comes next

The Fast Mode's report did not specify rollout timelines, pricing or first joint customers for the combined Calnex–VIAVI offer. Both companies already sell Open RAN-related test products independently, and the stated intent is to deepen integration between those portfolios as operator demand for multi-vendor RAN validation grows.