What security risks arise when bridging two remotely located OPC servers, and how does OPC Expert address them?
Bridging OPC servers across remote network segments introduces several security considerations that do not apply to local connections. These include the risk of data interception in transit, unauthorized access through open network ports, and the challenge of traversing firewalls without exposing the system unnecessarily. OPC Expert addresses these risks through encryption options, secure protocol support, and a single-port communication model that simplifies firewall management.
Data Interception and Encryption
When OPC data travels between two remote machines, it passes through network infrastructure that may be shared or potentially exposed. OPC Expert supports encrypted communication through OPC UA security profiles, including 128-bit and 256-bit encryption options using secure libraries from the OPC Foundation. This protects data in transit from eavesdropping and man-in-the-middle attacks. For environments where OPC Classic is in use, OPC Expert’s tunneling capability wraps that communication in a more secure transport layer to provide similar protection.
Firewall and Network Traversal
One of the persistent challenges in remote OPC communication is navigating firewalls without opening broad port ranges. OPC Expert uses a single-port communication model, which means network administrators need to permit only one port rather than configuring complex rules for multiple services. When security appliances such as firewalls interfere with data callbacks, OPC Expert dynamically switches between asynchronous and synchronous communication modes to maintain the connection without requiring additional firewall exceptions.
Authentication and Access Control
OPC Expert supports Windows authentication and OPC UA certificate-based security, which means connections between remote systems can be validated at the identity level rather than relying solely on network-level access controls. This is relevant when the bridge must operate across domain boundaries or when you need to ensure that only authorized machine identities can initiate or receive data.
Relevant Tools
OPC Bridge is the feature within OPC Expert that manages the data transfer between remote OPC servers, with built-in support for security barrier compensation and network fault handling. OPC Tunneler is the OPC Expert module specifically designed for secure cross-network OPC communication, offering DCOM-free connectivity with encryption and protocol conversion between OPC DA and OPC UA. OPC Security Gateway provides an additional layer of granular access control if your environment requires restricting which users or endpoints can read, write, or browse OPC data.
Remote OPC bridging is manageable from a security perspective when the right tools and configurations are in place. The combination of encryption, single-port communication, and authentication support in OPC Expert reduces the attack surface significantly compared to traditional DCOM-based remote OPC setups.