Protocol converter (Gateway)

A protocol gateway integrate automation components into the communication networks of modern systems that are usually incompatible with one another due to differences in technological status. Protocol Converter applications vary from industry to industry. The protocol converter can be a software converter, hardware converter, or an integrated converter depending on the protocols. There are varieties of protocols used in different fields like Power Generation, Transmission & Distribution, Oil & Gas, Automation, Utilities, AMR, and Remote Monitoring applications. The major protocol translation messages involve conversion of data messages, events, commands, and time synchronization.

The general architecture of a protocol converter includes an internal master protocol communicating to the external slave devices and the data collected is used to update the internal database of the converter. When the external master requests for data, the internal slave collects data from the database and send it to the external master. There will be different schemes for handling the spontaneous reporting of events and commands. There can be different physical medium for communication on protocol-X & Y, which include RS-232, RS-485, Ethernet, etc.

There are simple and complex types of conversions depending on the application and domain in which this is being used. The simplest and most commonly used conversion is protocol conversion between Modbus RTU and Modbus TCP. In this conversion, there is no change in the overall framing. Hence it is easy to take the Serial Modbus RTU frame and encapsulate it in a TCP/UDP socket and send it over Ethernet. Since both the protocol framings are the same, except for the actual physical layer transmission, both the application layers will interpret data similarly as long as the communication interfaces are made transparent.