Customer
German company specializing in device integration and management software development. Company holds a leading market position providing clients in the process industries (instrumentation and control systems vendors and plant operators) with reliable communication solutions.

Challenge
HART-IP is an easy-to-use, high-level application protocol that offers a straightforward way to access all information from HART-enabled field devices using the existing network infrastructure and allows this information to be easily migrated to the enterprise level, without the need for any translation processes, and losing information.
HART-IP server is a Linux-based application.
The customer wanted to update the HART-IP server with the following features: support for TCP communication with SSL/TLS based on OpenSSL library (no other libraries allowed); support for direct messaging between clients and field device; publishing events on a remote server; support for reset to hardware factory settings, where the HART-IP server is running.

Solution
Above all, our team had to prepare a complete environment like in the picture below. Missing components were replaced by stubs.


The development process was divided into three stages. After each stage, we delivered all components and a ‘green’ list of automated tests updated to the latest implemented features. Customer specialists checked the code, compiled and ran tests on their side.
Implemented the following tasks:

  • Refactoring of the HART-IP communication part to support TCP protocol along with UDP.
  • DirectMessage PDU in parallel with Token-Passing Data-Link Layer PDU to enable direct communication between clients and field devices.
  • Event logging into the system log.
  • Secure login to a remote server log.
  • Support for secure SSL/TLS communication via TCP/UPD.
  • Interfaces for the HART-IP server configuration – change of host and ports.
  • Support for reset to hardware factory settings, where the HART-IP server is running.

Results
As a result of our work, the customer received the updated functionality of the required HART-IP server, as well as a test client with automated tests. The solution we have developed enables secure remote access to devices to manage HART-enabled field devices for multiple clients simultaneously.