The OPC Tunneller from MatrikonOPC is used to establish and maintain secure, reliable OPC communications in today's complex network environments. The tuneller facilitates OPC connectivity across domains and workgroups, firewall compatibility, bandwidth optimization, timeout and disconnection recovery, and data encryption. Version 5.0 adds key system health monitoring and diagnostics tags to enable users to easily track the status of their connections, license information, and performance metrics. It also adds 64 bit support for both Client and Server side connections.