DNP3 Protocol - Usage In SCADA Systems For Critical Communications

The DNP3 or "Distributed Network Protocol" is widely used within the electrical and water utility industries. The DNP3 protocol is actually a set of communications protocols that are used for communications between SCADA (Site Control and Data Acquisition) system components. The DNP3 protocol was developed to provide for communication between SCADA system devices and Intelligent Electronic Devices (IED's).

SCADA Systems Use DNP3 for Critical Communications

The DNP3 protocol enables communication between various SCADA system components. These system components include the SCADA master or HMI (Human Machine Interface), the system's Remote Terminal Units (RTU's), and Intelligent Electronic Devices (IED's).


The DNP3 protocol travels from the individual network devices, which feed into the RTU's (Remote Telemetry Units). Once an RTU has collected a DNP3 protocol alarm, it forwards it to a DNP3 or SCADA system master. The master then interprets the alarm, and converts it into an alert that is human-readable. The master sends these DNP3 protocol communications to technicians instantly via email or pager, providing them with an alarm notification transcribing the alarm described in the DNP3 protocol message.

DNP3 Protocol Provides a Communication Medium for SCADA System Components

Prior to the development of the DNP3 protocol, it was impossible for SCADA devices and IED's manufactured by different vendors to communicate. Based off of IEC 60870-5, the DNP3 protocol provided for a communications medium that was usable by multiple vendors. This enabled system components to communicate with one another, and provided for DNP3 protocol communications across the SCADA stem.

SCADA system operators can monitor the DNP3 protocol within their operations to increase system reliability. This will reduce customer churn by decreasing downtime. The DNP3 protocol was designed to avoid being distorted by legacy equipment, as well as EMI noise and low-grade transmission channels. While it adds network reliability, the DNP3 protocol does not make provisions for communications security.

SCADA Systems Protect Your Operations

To protect your important DNP3 protocol communications, you need to gain visibility of your network by deploying a network alarm monitoring system. Advanced DNP3 protocol masters can monitor your DNP3 transmissions in addition to your other protocols, providing all of your alarm notifications in a single, convenient user window. Advanced masters will also provide you with alarm notifications through email or pager so that you and your technicians will know the location of DNP3 protocol communication problems immediately.

As a layer 2 transmission medium, the DNP3 protocol provides for data fragmentation, multiplexing, error checking, prioritization, and link control. The DNP3 protocol also provides addressing services for your important data. With so many important functions within your operation, your best is to monitor your DNP3 protocol communications with the most advanced DNP3 RTU's and master. Don't wait to achieve SCADA visibility. Seek out a DNP3 protocol monitoring solution today.

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