AI's chokepoint moved to the test bench, and three rivals just demonstrated the way around Keysight
At ECOC in Málaga yesterday, Advantest, VIAVI and SENKO demonstrated an automated line for testing co-packaged optics, an attempt to keep the AI buildout's validation bottleneck from hardening into a permanent toll. The toll's current collector, Keysight, reported its first billion-dollar commercial communications quarter in August and says demand now outruns its own capacity.
Richard Tang · 4 min read
At ECOC in Málaga this week, Advantest, VIAVI and SENKO demonstrated an automated production test line for co-packaged optics: 200 gigabits per second per lane, driven through a detachable tungsten-carbide connector rated for thousands of mating cycles, at the tens of thousands of modules a month that real production demands 1. It is the least glamorous corner of the AI buildout, and it is where the money now queues. Today the toll booth on that queue has one dominant name on it: Keysight.
Every new optical link must pass a verdict before it ships
The chain is physical. An AI cluster is limited by how fast data moves between chips, and copper tops out at roughly 72 GPUs per domain, by Credo's accounting, so the industry is rebuilding interconnects on optics, from 800G Ethernet to 1.6T with 3.2T in development 2. Dell'Oro research ties nearly all of the telecom equipment industry's first-half revenue growth to AI data center connectivity 3.
Each new optical engine is a device nobody has shipped before, and it must be validated from the physical layer through protocol before it enters a training run. That verdict is Keysight's wireline business, and the queue is no longer hypothetical: wireline revenue more than doubled year over year last quarter and passed wireless revenue for the first time 4.
The queue is now a billion-dollar quarter
The fiscal third quarter, ended 31 July, shows what that verdict does to an order book: orders of $2.09 billion, up 56% year over year, and commercial communications revenue above $1 billion for the first time, up 56% 5. The communications group, 73% of company revenue, grew 43%, with operating margin at 34% against 26% a year earlier 5. Management told investors demand is not the constraint; supply availability will govern how fast the pipeline converts to revenue 6.
Keysight's growth ran near 10% three quarters ago; the latest quarter is 36%
Data
| Revenue | |
|---|---|
| Q3 '24 | $1.29B |
| Q4 '24 | $1.3B |
| Q1 '25 | $1.31B |
| Q2 '25 | $1.35B |
| Q3 '25 | $1.42B |
| Q4 '25 | $1.6B |
| Q1 '26 | $1.72B |
| Q2 '26 | $1.85B |
The stock has answered: Keysight rose 102.6% over the past year against the industry's 91.3%, yet still trades at 25.6 times forward earnings, below the industry's 27.23 4. The market is paying for growth, not yet for a permanent toll.
Keysight's operating margin hugged 17% for two years, then jumped to 25%
Data
| Operating margin | |
|---|---|
| Q3 '24 | 17.9% |
| Q4 '24 | 16.8% |
| Q1 '25 | 15.8% |
| Q2 '25 | 17.3% |
| Q3 '25 | 15.3% |
| Q4 '25 | 15.5% |
| Q1 '26 | 23.7% |
| Q2 '26 | 25% |
Three rivals are industrializing the bench
The Málaga demo is the countermove. SENKO's vice president calls scalable manufacturing and testing among the most significant barriers to CPO deployment, and the trio's answer attacks exactly that link: a durable detachable connector, VIAVI's 1.6-terabit photonic test platform standing in for the optical engine, and Advantest automation ganged to test several engines at once 1. Note who is on both sides. VIAVI's network test revenue grew 69.2% in its latest quarter, faster than anything in Keysight's book, while it also supplies the consortium building a route around bench testing 4.
Keysight's own mix shift points the same way. Management said wireline demand has moved from a historical 80-20 split between R&D and manufacturing to roughly two-thirds and one-third, tilting toward production as 1.6-terabit transceivers ramp 6. Validation is bench work; production test is line work, and the line is what the consortium just demonstrated.
A qualification cycle has a clock on it
ECOC floor research expects optical engine volumes to reach single-digit millions next year and tens of millions in 2028 2. Demand of this kind is a transition, not an annuity: once 1.6T is a standard rather than a migration, the links still get tested, but the outsized growth rate does not survive a settled generation.
Nothing in these sources settles whether the surge is structural or cyclical; the hedges are 6G programs moving into funded development toward a first standard in 2029, and defense orders 4. Keysight guides its fiscal fourth quarter to about 37% growth 5. The next demand wave is dated too: ECOC floor research expects no named slow-and-wide deployment before the second half of 2027 2, so until then the bench fills with the current transition's links, not a new generation's.
The verdict is still Keysight's to lose
The decisive work of this buildout sits one hop below the models: turning photonics that work in the lab into modules that ship by the million, each one proven. The record shows Keysight collecting that toll while its capacity catches up, and three rivals building the line that would end it.
Watch whether engine volumes hit the millions expected in 2027, which moves test from bench to line, and whether orders keep setting records as supply loosens. Whoever industrializes the verdict captures the quiet margin of the AI buildout, and the queue still runs through Santa Rosa.
Deepdive
AI-generated from this story and its cited sources. Not investment advice.
