Sales Guide

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Product Overview
u About Modbus Protocol Versions
Modbus over UDP — Some have experimented with using Modbus over UDP on IP
networks, which remove the overheads required for TCP. 
Modbus Plus (Modbus+, MB+ or MBP) — Modbus Plus is proprietary to Schneider Electric
and unlike the other variants, it supports peer-to-peer communications between multiple
masters.
Pemex Modbus — This is an extension of standard Modbus with support for historical and
flow data. It was designed for the Pemex oil and gas company for use in process control and
never gained widespread adoption.
Enron Modbus — This is another extension of standard Modbus developed by Enron
Corporation with support for 32-bit integer and floating-point variables, and historical and
flow data.
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