Ambimat GroupAmbimatAmbiSecureV2XeSIMAmbiAutomationAhmedabad · India · Est. 1982
Product · AmbiRSU

AmbiRSU — roadside infrastructure, treated as infrastructure.

V2X networks need roadside units at intersections, toll plazas and highway on-ramps. India has effectively none, and no domestic manufacturer. A roadside unit is permanent outdoor infrastructure carrying real-time road-safety communications, which makes it a rather different engineering problem from a piece of traffic equipment that only reports upward.

AmbiRSU is a development platform, and we are looking for collaborators and launch customers — road authorities, tolling and transit concessionaires, telecom operators, city ITS programmes and integrators. If you are scoping a corridor, an intersection programme or a pilot, that is the conversation we want.

1 · Why RSU security is different

A compromised roadside unit is a weapon, not a fault.

An RSU that broadcasts unsigned messages, or whose firmware can be silently replaced, can inject false traffic alerts, spoof emergency-vehicle signals, or disable collision warnings across an entire corridor — continuously, from a fixed and well-chosen position, to every vehicle in range.

It is also a trusted insider in the PKI. Roadside units hold application certificates with service-specific permissions that vehicles do not have: an RSU may sign SPaT, MAP and IVI messages; a vehicle may not. Compromise it and you inherit those permissions. How those permissions are encoded →

2 · Security architecture

Eight requirements, and how the platform meets each.

RequirementAmbiRSU implementation
PKI certificate managementAmbiSEC secure element manages V2X certificates; automated issuance, renewal and revocation over the backhaul
Signed messagesEvery V2X broadcast signed with ECDSA; relays validate authenticity before forwarding
Secure OTAFirmware authenticated by the secure element before installation; rollback protection on failed update
Hardware-backed credential storageRSU identity keys and V2X certificates held in the hardware-isolated secure element
Secure bootBoot sequence cryptographically verified before the unit becomes operational
Tamper detectionAnti-tamper mesh on the PCB triggers alarm and credential wipe on physical breach — critical for unattended roadside deployment
Unique device identityHardware-bound identity provisioned at manufacturing under HSM custody, SCP03-wrapped
Application permissionsMessage permissions scoped in the certificate — an RSU signs only the message types its service-specific permissions authorise

That last row is worth dwelling on. Permissions are carried in the certificate itself, as a PSID and SSP pair, so what a device is allowed to say is enforced cryptographically rather than by configuration. Separating credentials by application is therefore a design decision taken once, at architecture time — it is not something that can be added later in software.

3 · The ruggedisation heritage

Outdoor electronics designed for defence and space applications.

Ambimat designs ruggedised outdoor electronics for defence and space applications through AmbiSpace and AmbiDefence — IP-rated enclosures, thermal management, vibration tolerance. AmbiRSU applies the same security architecture as AmbiOBU, adapted for fixed infrastructure deployment with a multi-sensor environmental payload and cellular backhaul.

The sensor stack and full specification are pending client-supplied requirements, and no sensor table is published until they are confirmed.

4 · Who may operate an RSU

An open question in India, and one worth engaging publicly.

Our position: authorisation should be a licence with a security bar, not a procurement footnote.

Plausible operator classes: licensed telecom operators, who already hold spectrum, tower estate, backhaul and 24×7 network operations discipline; cloud and software infrastructure providers, who can run the ITS application layer, edge compute and credential-management back end; and highway, tolling and transit concessionaires, who own the roadside asset, power and access rights on the corridors that matter first and have a commercial reason to maintain the units.

Conditions of authorisation should include certified, MTCTE-tested equipment with a tamper-resistant secure element and secure boot; enrolment as an end entity under an approved Root CA with an audited Certification Practice Statement and no self-signed roadside trust; physical-security and tamper-response obligations at the pole with incident-reporting SLAs; and strict separation of safety-message permissions from commercial-service permissions. Where the Indian position currently stands →

5 · Scope, stated plainly

A development platform, not a product you can order.

AmbiRSU is not in production deployment. Engagement is co-development against a real site.

What we bring: ruggedised outdoor electronics design and manufacturing from the AmbiSpace and AmbiDefence programmes; multi-sensor PCB integration; cellular backhaul design; the AmbiSEC security layer with tamper detection, secure boot and hardware-held credentials; and OTA and provisioning infrastructure.

What we are looking for in a partner: a corridor, an intersection set or a campus to design against; the traffic-controller and command-centre systems it has to integrate with; and the conformity regime it will be tested under. The eight integration surfaces →

6 · Commercial and development services

Work we take on beyond the platform itself.

Commissioned development work around roadside infrastructure — custom RSU hardware to a published specification, sensor payload integration, secure-element and credential-lifecycle integration into an existing RSU design, provisioning-line design, and firmware and OTA work for deployed roadside fleets.

If you are building roadside infrastructure and need a hardware partner rather than a finished box, reach out. Commercial arrangements — co-development, licensing, contract manufacture, joint pilots — are all things we will discuss directly.

Scoping a roadside deployment or an RSU development programme?

Bring the corridor, the controller integration and the conformity regime. We will bring the hardware baseline and the security architecture.

Discuss RSU development