On 28 September 2026 Ciena announced that CtrlS is building five metropolitan optical networks connecting nine of its existing data centres across Chennai, Hyderabad, Kolkata, New Delhi and Noida, delivering up to 100 terabits per second. It is part of a larger managed optical fibre network deployment for a hyperscale customer that neither company has named. This record carries no data-centre capacity. It is here because it marks the point where India’s largest Rated-4 operator stopped selling floor space and started selling light.
1At a glance
2What was deployed
| Component | Role |
|---|---|
| WaveLogic 5 Extreme | Ciena’s coherent optical engine, capable of carrying up to 800 Gb/s on a single wavelength of light |
| Waveserver platform | Compact optical transport purpose-built for data centre interconnection — the box at each end of a link |
| 6500 Reconfigurable Line System | The optical transport layer in the middle, giving a programmable photonic path that can be provisioned and re-routed without physical changes |
| Navigator Network Control Suite | Software that automates network operations and speeds up provisioning of new services |
| Ciena Services | End-to-end project management for the deployment |
The reconfigurable line system is the part that matters commercially. It means CtrlS can provision a new wavelength path between two of its buildings in software rather than sending engineers to patch fibre. For a customer buying connectivity as a service, that is the difference between a delivery timeline measured in weeks and one measured in hours.
3100 Tb/s, translated
One hundred terabits per second is a number most people cannot place. Four ways to make it concrete:
| Measure | Figure | Note |
|---|---|---|
| At 800 Gb/s per wavelength | about 125 wavelengths | Derived. The physical light paths the system provisions |
| Across five metros | 20 Tb/s each | Derived. Average, not a published per-city figure |
| Across nine data centres | about 11.1 Tb/s each | Derived. Average |
| Per second | about 12.5 terabytes | Derived from 100 Tb/s at 8 bits to a byte |
| A 50 GB model file | transferred in about 4 milliseconds | Idealised, at full line rate across the whole network |
The useful comparison is not speed but shape. This is not a link between two buildings; it is a ring around five Indian cities with 125 wavelengths of capacity that can be re-pointed at will. It exists because AI workloads move enormous volumes of data between facilities — training data, checkpoints, model replicas — and that traffic runs east to west between data centres rather than out to users.
100 Tb/s is not 100 MW, and it is not 100 of anything a data centre buyer orders. Network throughput and electrical capacity are unrelated units that appear together in press releases constantly.
Gridvik’s registry carries this record with zero capacity. Anyone adding a network figure to a capacity total is producing a number that means nothing.
4Nine existing buildings, not nine new ones
The single most misread element of this announcement is the phrase "nine data centres". These are buildings CtrlS already operates. The project adds fibre and optical equipment between them, not concrete.
| New | Not new |
|---|---|
| Optical transport equipment in nine existing buildings | The nine data centres themselves |
| About 125 wavelengths of coherent capacity | Any data-centre capacity, rack or megawatt |
| Metro fibre routes between the buildings | The operator’s 370 MW of live capacity |
| A managed network service layer | The 4.4 GW of projects at various stages of execution |
The cities are also worth noting as a set. Chennai, Hyderabad, Kolkata, New Delhi and Noida — but not Mumbai, which is India’s largest data centre market and where CtrlS operates several facilities. The release does not explain the omission, and Gridvik does not assume the reason.
Two possible readings. Either Mumbai connectivity was already in place and this programme extends the model to the other metros, or this is a first phase and Mumbai follows. Both are consistent with what was announced.
5Why a managed network is a different business
This is the part worth paying attention to, because it changes what CtrlS is.
Ciena’s own numbers show why this model is spreading. In its fiscal third quarter of 2026, direct cloud-provider revenue rose 82% year on year and represented 53% of company revenue, with revenue from the Reconfigurable Line System and Waveserver both up more than 55%. Hyperscalers are buying optical transport in volume, and increasingly they are buying it through regional operators rather than directly.
For an Indian data centre operator, that is the most attractive business in the market right now: it uses assets you already own, sells to a customer with almost unlimited bandwidth appetite, and raises switching costs without requiring another megawatt of power.
6The customer nobody will name
Every party in this announcement is named except the one paying for it. Neither CtrlS nor Ciena identifies the hyperscaler, the contract value, the deployment schedule, or whether all five networks go live together.
That is normal. Managed optical fibre network agreements are usually confidential, because the hyperscaler does not want its Indian network topology in the public domain.
| Question | Public answer |
|---|---|
| Who is the customer? | A leading hyperscaler. Not named |
| How much is the contract worth? | Not disclosed |
| When does it complete? | No date given |
| Do all five metros go live together? | Not specified |
| Is this a multi-year service agreement or a one-off build? | Not specified |
| Which CtrlS buildings are the nine? | Not individually identified |
The reasonable inference — and it is an inference, clearly labelled — is that a single hyperscaler wanting low-latency links between five Indian metros, buying through CtrlS rather than building itself, is most likely one of the three or four global cloud platforms with an established Indian presence. Gridvik does not guess which one.
The relevant opportunity is not the data centres. It is the fibre. Five metro networks require ducts, cable, optical equipment, regeneration sites, and power and cooling in small roadside or in-building enclosures across five cities.
That last category is systematically ignored by the data centre supply chain and it is a real, repeating order.
7Timeline
- Ciena announces that CtrlS is building five metro optical networks connecting nine existing data centres across Chennai, Hyderabad, Kolkata, New Delhi and Noida, for up to 100 Tb/s, as part of a managed optical fibre network deployment for an unnamed hyperscaler.
- Indian and international trade coverage repeats the figures. No coverage adds a contract value, a schedule or a customer name
- No completion date, contract value, customer identity or per-metro capacity has been published. The nine buildings are not individually identified
8Procurement
Rows with a lock are the paid layer.
9Assumptions and method
10Limits and open questions
11Sources
This record was compiled entirely from publicly available sources, cross-checked against one another.
Ciena press release·Economic Times·Economic Times Datacenters·The Hindu BusinessLine·CXO Digitalpulse·Converge Digest·Telecom TV·Construction World·Yahoo Finance·CIO and Leader·The420
Gridvik does not publish source URLs on record pages; citations are retained in the internal source register and are available on request.
A connectivity record. It carries no data centre capacity, by design and by rule.
Corrections are free and published with a date.