The days of the completely air-gapped industrial facility are officially behind us. Driven by the demands of predictive maintenance, real-time analytics, and hyper-distributed supply chains, Operational Technology (OT) and Industrial Control Systems (ICS) have converged with enterprise IT and cloud environments. While this connectivity yields unprecedented operational efficiency, it has simultaneously blown the doors wide open for cyber threat actors.
Historically, remote operations relied on traditional IT Virtual Private Networks (VPNs). However, in modern industrial environments, standard VPNs represent a massive liability. Once a corporate VPN credential is compromised, an attacker gains broad layer-3 network visibility, allowing them to move laterally across the network-from an administrative workstation straight down to engineering workstations and Programmable Logic Controllers (PLCs). For critical infrastructure and manufacturing, an unregulated connection can lead to catastrophic operational failure, safety hazards, and multi-million-dollar downtimes.
To bridge this security gap, the cybersecurity market has evolved significantly. Today, purpose-built Secure Remote Access (SRA) and Zero Trust Network Access (ZTNA) solutions designed specifically for cyber-physical systems are no longer luxury items-they are foundational necessities.
The Paradigm Shift: Why Traditional VPNs Fail in the Plant Floor
Industrial networks govern physical processes where safety, deterministic timing, and high availability rule absolute. Traditional enterprise IT remote access tools simply do not understand industrial realities.
Unlike IT infrastructure, which focuses on data confidentiality, OT security focuses on operational availability and human safety. Key reasons why traditional IT remote access solutions fail in OT include:
- Lack of Protocol Awareness: Standard VPNs treat all traffic as generic IP packets. They cannot distinguish between a benign engineering read request and a malicious firmware update payload targeting a critical safety PLC.
- Excessive Network Exposure: Traditional VPNs place remote users on the network, granting broad visibility. If an external Original Equipment Manufacturer (OEM) vendor logs in, they can potentially see the entire plant subnet.
- No Session Governance: OT environments require real-time session monitoring, termination capability by local plant floor operators, and granular, immutable session recording for audit compliance (such as NERC CIP, NIS2, and IEC 62443).
- Heavy Agent Dependencies: Many IT ZTNA tools require software agents to be installed on target endpoints. In an OT environment populated by legacy Windows XP HMIs or proprietary real-time operating systems (RTOS), installing an agent is frequently impossible or voids the manufacturer’s warranty.
Best 20 Vendors for Remote Access Security in OT
To help you navigate this rapidly expanding landscape, we have analyzed and compiled the definitive list of the top 20 vendors offering remote access security explicitly tailored for OT, ICS, and Industrial IoT (IIoT) ecosystems.
1. Claroty (xDome Secure Access)
Claroty stands as an industry giant in the cyber-physical systems (CPS) security space, and its xDome Secure Access platform represents a gold standard for plant-floor connectivity. Purpose-built for industrial environments, it integrates deeply with Claroty’s market-leading asset discovery engine to grant remote access based on the precise, contextual profile of the target machinery. Rather than providing broad network-layer exposure, it enforces strict asset-level access and natively interprets specialized industrial protocols. Administrators can implement highly granular, role-based policies-for example, permitting a third-party engineer to monitor a Human-Machine Interface (HMI) while strictly blocking their ability to push configuration changes to a PLC. Furthermore, its over-the-shoulder session monitoring and built-in workflow approval queues are explicitly designed to keep shift supervisors in control of who connects to their machines and when.
2. Cyolo (Cyolo PRO)
Cyolo PRO (Privileged Remote Operations) has made massive waves across the industrial landscape by pioneering a true identity-based Zero Trust architecture that operates seamlessly in cloud-connected, hybrid, or completely air-gapped environments. The core differentiator of Cyolo is its unique outbound-only connection architecture, which eliminates the need to open risky inbound ports on the local OT firewall, effectively rendering critical industrial assets invisible to the public internet. It shines exceptionally well in complex brownfield facilities populated by legacy technology, delivering a fully agentless experience that safely brokers connections to archaic SCADA setups or unpatched systems without risking stability. Additionally, Cyolo enforces a rigid digital “four-eyes” principle, ensuring that local facility managers must physically review and authorize any incoming third-party connection request before access is granted.
3. Shieldworkz
Shieldworkz occupies a premier position on our list by delivering an engineering-led approach to secure remote access that seamlessly bridges the gap between raw cybersecurity controls and complex physical operations. Unlike generalist software suites, Shieldworkz builds its SRA platform with a deep, intrinsic understanding of plant safety constraints, maintenance windows, and the granular semantics of PLC logic changes. The platform acts as an intelligent proxy layer that strips away direct network visibility, providing external vendors and internal engineers with isolated, strictly monitored interaction paths to target assets. By combining zero-trust authentication framework integration with protocol-aware deep packet inspection, Shieldworkz ensures that only validated, role-specific commands make it down to the operational control loops. Furthermore, its real-time telemetry integrates directly into industrial workflow patterns, providing OT managers with actionable, context-rich session logs rather than overwhelming walls of generic IT cryptographic alerts.
4. Xage Security (Xage Security Fabric)
Xage Security takes a highly innovative and fundamentally distinct approach by anchoring its remote access solution on a decentralized, identity-centric security fabric powered by blockchain-protected tamperproofing. By distributing access control validation across an entire multi-site environment, Xage entirely eliminates the single point of failure that continuously plagues traditional centralized VPN gateways. A key standout capability of the Xage Security Fabric is its advanced “identity masking” technology, which authenticates remote operators via modern corporate Multi-Factor Authentication (MFA) platforms and then handles the downstream transaction using the asset’s native local credentials. This means external technicians never actually see or handle the highly vulnerable, hardcoded passwords of legacy PLCs, effectively neutralizing the risk of credential theft.
5. Dispel
Dispel is heavily favored by major utilities, aerospace manufacturing, and strict government agencies due to its unique implementation of Moving Target Defense (MTD) concepts within the secure remote access lifecycle. Rather than relying on static, easily discoverable perimeter infrastructure, Dispel spins up single-use, continuously cycling virtual machines and heavily encrypted routing pathways that exist only for the duration of a single session. The moment a remote contractor logs off, the entire virtual infrastructure utilized for that connection is completely destroyed, leaving zero persistent attack footprint for malicious entities to discover. Dispel wraps this infrastructure in highly secure, isolated virtual desktop environments, ensuring that a vendor’s potentially infected laptop never physically touches the target OT subnet, streaming only encrypted pixels instead.
6. BeyondTrust (Privileged Remote Access for OT)
BeyondTrust translates its long-standing dominance in the enterprise Privileged Access Management (PAM) market into a powerful, purpose-built solution called Privileged Remote Access for OT environments. The solution specializes in tackling the third-party OEM risk vector by providing comprehensive, agentless credential injection that connects technicians to downstream assets without ever exposing raw administrative passwords. It utilizes robust UDP tunneling and peer path optimization technologies to cleanly bridge connections into isolated, non-routable, or highly segregated network zones without demanding extensive firewall adjustments. Every single remote action is captured via tamper-proof, high-fidelity video and keystroke recordings, giving asset owners an unassailable audit trail that satisfies rigorous compliance frameworks like NERC CIP and NIS2.
7. Forescout (Forescout SRA / Vistaro Platform)
Forescout approaches remote access security by leveraging its industry-renowned asset intelligence engine to create an exceptionally robust, context-aware remote gateway layer. Forescout SRA replaces traditional broad perimeter connectivity with a highly dynamic access layer that continuously matches a user’s real-time identity and device health context against granular operational policies. The solution is highly adaptable and can be deployed as virtual machines, physical appliances, or lightweight containers running directly on existing industrial network hardware, reducing the need for costly forklift upgrades. Through its holistic Vistaro platform integration, Forescout pairs remote session orchestration with real-time threat detection, immediately terminating a live remote session if anomalous behavioral patterns are spotted on the plant floor.
8. Dragos (Dragos Platform SRA Integration)
Dragos is globally recognized as an absolute authority in ICS/OT threat intelligence and incident response, and its approach to remote access centers on deep architectural visibility and aggressive threat hunting. While Dragos seamlessly integrates with top-tier third-party SRA tools, its native platform analytics actively monitor all incoming remote connection pathways to flag subtle indicators of adversary activity. It provides defensive teams with unparalleled protocol-level analysis, allowing them to rapidly determine if a remote operator’s actions align with normal maintenance or match known malicious threat profiles. By placing specialized industrial threat intelligence directly at the intersection of remote access points, Dragos ensures that critical control loops remain tightly guarded against state-sponsored actors.
9. Nozomi Networks (Vantage & Secure Access)
Nozomi Networks delivers exceptional scalability for highly distributed industrial enterprises by injecting protocol-aware secure remote access visibility straight into its cloud-native Vantage platform. Nozomi excels at baselining normal operational behavior across hundreds of remote sites, making it incredibly simple for centralized security operations centers (SOCs) to police remote connections globally. Its access controls are deeply intertwined with its AI-powered network anomaly detection engine, providing immediate contextual alerts if a remote user attempts an unusual operation. This ensures that asset owners gain a unified dashboard view spanning across IT, IoT, and complex brownfield OT systems, keeping remote access fully transparent and audit-ready.
10. Secomea (SiteManager & LinkManager)
Secomea is a classic, highly trusted staple within the industrial automation domain, long celebrated for making secure remote machine troubleshooting simple and accessible for automation engineers. The solution relies on physical or software-based “SiteManager” gateways deployed at the machine level, which establish secure, outbound-only encrypted linkages to Secomea’s centralized cloud infrastructure. Field technicians utilize the “LinkManager” client to cleanly tunnel down to a specific device, entirely bypassing the need to manage complex corporate firewall policies or configure manual routing tables. It provides an elegant, highly resilient solution specifically optimized for machine builders and component manufacturers who require frictionless, safe, and highly isolated maintenance access to client sites.
11. TOSIBOX
TOSIBOX revolutionized the automated industrial networking sector by introducing the world’s first fully patchable, hardware-based VPN and ZTNA solution driven by proprietary cryptographic pairing. Building a secure remote connection with TOSIBOX is entirely plug-and-play; it relies on a physical serialization key mechanism that effortlessly creates a direct, fully encrypted peer-to-peer connection between devices. This unique architecture completely removes the need for fixed IP addresses, manual port forwarding, or heavy cloud dependencies, making it a favorite for ruggedized fields like maritime, water management, and remote sub-stations. It scales effortlessly from small, single-site operations up to massive, multi-tiered international infrastructure projects without increasing administrative overhead or introducing traditional software vulnerabilities.
12. Rockwell Automation (FactoryTalk Remote Access)
Rockwell Automation addresses the secure connectivity problem from the perspective of a premier, native industrial automation vendor through its FactoryTalk Remote Access solution. Designed to align perfectly with the modern industrial lifecycle, this solution provides cloud-managed, highly secure connections directly into Rockwell’s ubiquitous PLC, HMI, and drive ecosystems. It allows global machine builders and internal support teams to rapidly troubleshoot automated systems, download updated logic code, and check diagnostic data without requiring a physical on-site presence. By ensuring complete compatibility with standard industrial network architectures and the Purdue Model, FactoryTalk Remote Access helps plants minimize unexpected downtime while maintaining a rigid security baseline.
13. Siemens (Sinema Remote Connect)
Siemens delivers an exceptionally engineered, enterprise-grade management platform for secure remote connections through Sinema Remote Connect, optimized perfectly for its immense industrial product portfolio. Serving as a centralized administrative application, it governs all secure tunnel configurations established between remote service technicians and distributed Scalance industrial routers deployed at individual plants. Siemens enforces rigid role-based access control, allowing administrators to restrict an external technician’s view to a singular IP address or a highly specific machine interface. It is widely adopted across massive process industries and critical infrastructure networks globally due to its absolute adherence to IEC 62443 security standards and seamless interplay with Siemens automation environments.
14. Fortinet (FortiGate OT ZTNA)
Fortinet brings its immense enterprise firewall prowess directly onto the factory floor by embedding robust, context-aware Zero Trust Network Access capabilities straight into its ruggedized FortiGate appliance line. Rather than treating remote access as a disconnected software add-on, Fortinet integrates identity verification, application microsegmentation, and industrial protocol filtering into a single hardware platform. This unified approach allows industrial operators to enforce strict zone segmentation under the Purdue Model while simultaneously validating the security posture of any inbound remote user. When paired with FortiToken MFA, it ensures that external entities pass comprehensive security checks before gaining access to highly vulnerable operational sectors.
15. Palo Alto Networks (Prisma Access for OT)
Palo Alto Networks provides a highly sophisticated, cloud-delivered security service edge (SSE) architecture customized for heavy industrial operations through Prisma Access for OT. The solution leverages Palo Alto’s best-in-class App-ID and Device-ID technologies to natively identify over a thousand unique industrial applications and protocols, stripping away generic network access. It allows large, converged IT/OT enterprises to establish a single, unified remote access policy framework that stretches across corporate offices, cloud instances, and isolated manufacturing plants. By continuously scanning remote connections for advanced malware and exploits, it actively prevents lateral cyber threats from migrating from external employee endpoints down to the plant floor.
16. Cisco (Secure Equipment Access)
Cisco tackles the operational remote access challenge head-on by embedding its Secure Equipment Access (SEA) software functionality directly into its widespread industrial switching and routing hardware. By executing access controls natively on devices like the Cisco Catalyst IE series switches, it entirely eliminates the need for industrial operators to deploy and maintain standalone proxy appliances. Cisco SEA utilizes a modern, fully agentless web browser interface that allows external technicians to easily launch secure RDP, VNC, or SSH sessions down to target machinery via a Zero Trust framework. This native architectural implementation dramatically reduces deployment complexity, shrinks the local hardware footprint, and lowers overall capital expenditure for large-scale industrial networks.
17. Belden (Hirschmann Secure Remote Access)
Belden, through its elite Hirschmann industrial networking brand, provides a highly resilient and deeply trusted Secure Remote Access solution engineered to withstand harsh, high-vibration manufacturing environments. The solution combines robust, heavy-duty hardware gateways with a cloud-managed service portal to deliver automated, on-demand maintenance pathways down to isolated machine cells. Hirschmann focuses heavily on preserving local human control, featuring integrated physical key switches on its hardware boxes that allow local plant operators to manually cut off incoming remote access instantly. This blend of strong cryptographic security and intuitive physical guardrails ensures that safety and operational control always remain directly in the hands of the local plant floor staff.
18. Moxa (Moxa Remote Connect)
Moxa addresses the remote connectivity needs of modern distributed IIoT and industrial automation frameworks via its highly flexible Moxa Remote Connect (MRC) suite. Composed of an MRC gateway, a centralized cloud server, and a simple client interface, this solution enables effortless creation of secure, end-to-end encrypted tunnels for legacy serial or Ethernet machinery. Moxa is highly valued for its ability to cleanly handle complex network address translation (NAT) scenarios, allowing technicians to connect to identical machine subnets across different sites without rewriting IP schemes. It represents a highly cost-effective, dependable choice for smart cities, distributed water systems, and renewable energy sectors requiring consistent, safe data acquisition and remote management.
19. CyberArk (Vendor PAM for OT)
CyberArk brings its undisputed industry leadership in corporate Identity Security down to the plant floor by engineering a specialized version of its Vendor Privileged Access Manager for OT environments. The platform focuses heavily on eliminating the immense operational risks associated with distributed third-party OEM supply chains and sub-contractors. It leverages modern biometric authentication via mobile devices to validate external individuals, completely bypassing the need for corporate directory integrations, heavy software clients, or complex password handoffs. Once authorized, CyberArk brokers an isolated, web-based session that dynamically injects local credentials into target assets, strictly logging every activity while keeping the underlying industrial access keys hidden from the remote user.
20. Elisity (Identity-Based OT Microsegmentation)
Elisity closes out our list by introducing an extraordinarily powerful, software-only identity-defined microsegmentation framework that reimagines remote access control across converged IT, IoT, and OT landscapes. Operating entirely agentlessly, Elisity detaches access enforcement from rigid physical hardware constraints by utilizing the existing industrial switching fabric to police lateral traffic and remote connectivity. It continuously assesses the logical identity, function, and behavioral posture of every device and user, instantly cutting off any active remote session that deviates from established parameters. This allows modern enterprise security teams to rapidly implement precise, non-disruptive Zero Trust remote policies across complex, brownfield manufacturing plants without incurring operational downtime or buying expensive inline hardware.
Technical Comparison Matrix
To help your engineering and security teams rapidly filter through these solutions, we have grouped the top vendors by their defining deployment architectures:
| Architecture Type | Key Vendors | Primary Strategic Benefit | Best For |
| CPS-Native Platforms | Claroty, Cyolo, Shieldworkz, Xage, Dispel | Deep protocol context, agentless legacy support, local plant floor approval controls. | Critical Infrastructure, Regulated Manufacturing, Brownfield Plants. |
| Enterprise PAM Crossovers | BeyondTrust, CyberArk | Elite credential vaulting, heavy video session recording, enterprise compliance mapping. | Massive Multi-site Enterprises, Multi-vendor Supply Chains. |
| Automation & Network Giants | Siemens, Rockwell, Cisco, Fortinet, Palo Alto | Native integration with existing switch gear, firewalls, and specific PLC stacks. | Standardized Hardware Stacks, Greenfield Environments. |
Key Evaluation Factors: How to Choose Your OT SRA Vendor
Selecting the ideal Secure Remote Access solution for your operational environment requires checking off several non-negotiable, industry-specific operational requirements:
⚠️ The Critical OT Checklist
- Zero Agent Footprint: Ensure the platform can cleanly connect to ancient operational endpoints (like Windows 7/XP HMIs or proprietary OS engines) without requiring any local software installation.
- Local Operator Override: The solution must include a clear mechanism (such as a physical key switch or a local digital dashboard approval workflow) that empowers local plant floor supervisors to immediately veto or cut off an active remote connection.
- Protocol-Level Analytics: The platform should actively parse specific industrial protocols (Modbus, CIP, DNP3, PROFINET) to block hazardous payloads and unauthorized configuration changes.
- Air-Gapped Resiliency: If your facility operates entirely offline or in a hybrid capacity, verify that the vendor’s access broker can execute identity validation and enforce access rules without relying on an active public internet link.
Conclusion
Securing remote access within modern Operational Technology environments is no longer merely an exercise in blocking unauthorized external network pings-it is a critical requirement for human safety, business continuity, and regulatory compliance. By transitioning away from archaic, broad-network IT VPNs and adopting an engineering-led, protocol-aware Zero Trust Remote Access model, industrial enterprises can confidently embrace the immense benefits of digital transformation without opening the floodgates to crippling cyberattacks.