# 12 DNP 3.0 # 12.1 Introduction DNP3 (Distributed Network Protocol) is a set of communications protocols used between components in process automation systems. Its main use is in utilities such as electric and water companies. It was developed for communications between various types of data acquisition and control equipment. It plays a crucial role in SCADA systems, where it is used by SCADA Master Stations (a.k.a. Control Centers), Remote Terminal Units (RTUs), and Intelligent Electronic Devices (IEDs). It is primarily used for communications between a master station and RTUs or IEDs. ICCP, the InterControl Center Communications Protocol (a part of IEC-608706), is used for intermaster station communications. Elseta’s DNP3 stack has both Master and Slave protocols implemented. Both of them can serve multiple serial (over physical RS485 line), TCP or TLS (over TCP) connections with high efficiency. IEEE1815 defines 4 subset levels (14) that consist of the objects and function codes that must be supported by the master and outstation. Levels 13 are supported fully and level 4 is supported partially. To get more information about how DNP3 works and what capabilities are supported one should get a copy of the protocol specification and/or check the Slave Interoperability List/Configuration guides for both Master and Slave protocols.

To set up TLS connection for both DNP3 Master and Slave, refer to sections Excel configuration and Certificates. All keys and certificates should be provided in the PEM format.

If no configuration is set up, DNP3 Master and Slave services are not started.

# 12.2 DNP 3.0 Master Default groups and variation sets are used to send commands. If slave devices support different groups and variations, they can be adjusted in Excel configuration. For more information check section [Excel configuration](https://wiki.elseta.com/books/manual/chapter/18-excel-configuration). #### Configuring data points To use DNP3 Master in WCC Lite, it has to be configured via an Excel configuration. This configuration contains two Excel sheets where parameters have to be filled in Devices and Signals. ##### DNP3 Master parameters for Devices tab

Parameter	Type	Description	Required		Default Value (when not specified)	Range
Parameter	Type	Description	TCP/ TLS	Serial	Default Value (when not specified)	Min	Max
name	string	User-friendly device name	Yes	Yes
description	string	Description of a device	No	No
device\_alias	string	Alphanumeric string to identify a device	Yes	Yes
enable	boolean	Enabling/disabling of a device	No	No	1	0	1
protocol	string	Protocol to be used (”dnp3 serial”/”dnp3 tcp” (case insensitive))	Yes	Yes		DNP3 TCP, DNP3 serial
mode	string	Choosing between TCP, TLS and SERIAL modes. If the protocol provided DNP3 TCP mode defaults to tcp and if DNP3 serial is provided mode defaults to serial	No	No	TCP (for DNP3 TCP) SERIAL (for DNP3 serial)	TCP, TLS (for DNP3 TCP) SERIAL (for DNP3 serial)
host	string	The IP address of the TCP slave device	Yes	-
bind\_address	string	The IP address of the network adapter used to connect to the slave device	No	No	0.0.0.0
port	integer	TCP communication port	No	No	20000
device	integer	Communication port (”PORT1” or ”PORT2”)	-	Yes
baudrate	integer	Communication speed, bauds/s	-	No	9600	300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600,115200
databits	integer	Data bit count for communication	-	No	8	6	9
stopbits	integer	Stop bit count for communication	-	No	1	1	2
parity	string	Communication parity option	-	No	none	none, even, odd
flowcontrol	string	Communication device flow control option.	-	No	none	none
tls	boolean	Enable/disable the use of TLS	Yes (for TLS)	-	0	0	1
tls\_local\_certificate	string	Local certificate for TLS connection	Yes (for TLS)	-
tls\_peer\_certificate	string	Certificate authority file for TLS connection	No (for TLS)	-
tls\_private\_key	string	A file consisting of the private key for TLS connection	No (for TLS)	-
max\_rx\_frag\_size	integer	Maximum size of a received fragment.	No	No	2048	0	2048
destination\_address	integer	Address of a master station	No	No	1	0	65535
source\_address	integer	Address of a slave (local) station.	No	No	1	0	65535
unsol\_classes	string	Defines which classes will have unsolicited actions on startup. (Example: "1,3,2")	No	No	no class	1	3
unsol\_disable	bool	Disables unsolicited messages on startup. The parameter is going to be ignored if the unsol\_classes parameter has any values assigned.	No	No	0	0	1
groups\_scan\_mask	integer	Bitmask for enabling separate group scans with x06 qualifier (all objects). The parameter value is converted into a binary number where each bit stands for a separate group. Bits indexes and the groups that they represent: 0 - Binary, 1 - Doublebit Binary, 2 - Binary Output Status, 3 - Counter, 4 - Frozen Counter, 5 - Analog, 6 - Analog Output Status, 7 - Octet String (Example: 115 (0111 0011) will trigger data polls for signals whose types are - Binary, Doublebit Binary, Frozen Counter, Analog, Analog Output Status)	No	No	0	0	255
groups\_scan\_interval	integer, string	The time between separate groups scans intervals in seconds. Set to 0 to disable.	No	No	0	0
exception\_scan\_interval	integer, string	The time between exception scan (classes 1,2,3) intervals in seconds. Set to 0 to disable.	No	No	0	0
integrity\_scan\_interval	integer, string	Time between integrity scan (classes 0,1,2,3) intervals in seconds (general interrogation). Set to 0 to disable.	No	No	0	0
timesync\_mode	string	Will override the master default setting for choosing the time sync procedure	No	No	NON-LAN (for Serial) LAN (for tcp)	LAN, NON-LAN
time\_sync\_interval\_sec	integer, string	Periodic time sync interval in seconds. If > 0 - time syncs are forced and periodic. If = 0 - time syncs react to IIN bits from the slave. If < 0 - time syncs are disabled.	No	No
select\_ms	integer	Select command timeout. Valid for all signals.	No	No	10000
timeout\_ms	integer	Response timeout in milliseconds	No	No	2000
keep\_alive\_timeout	integer	The time interval for sending a keep-alive packet in milliseconds.	No	-	60
use\_local\_time	boolean	if enabled (1) communication uses system time instead of UTC.	No	No	0	0	1

##### DNP3 Master parameters for the Signals tab

Parameter	Type	Description	Required		Default Value (when not specified)	Range
Parameter	Type	Description	TCP	RTU	Default Value (when not specified)	Min	Max
signal\_name	string	User-friendly signal name	Yes	Yes
device\_alias	string	Device alias from a Devices tab	Yes	Yes
signal\_alias	string	Unique alphanumeric name of the signal to be used	Yes	Yes
enable	boolean	Enabling/disabling a device	No	No	1	0	1
index	integer	Index of a signal.	Yes	Yes		0	65535
log	boolean	Enable logging in the event log	No	No	0	0	1
signal\_type	string	DNP3 signal type. (case insensitive)	Yes	Yes		”binary”, ”doublebitbinary”, ”binaryoutputstatus”, ”binaryoutputcommand”, ”counter”, ”frozencounter”, ” analogue”, ”analogoutputstatus”, ”analogoutputcommand”, ”timeandinterval”, ”octetstring”
command\_variation	integer	DNP3 command variation. Supported variations depend on signal type and are provided in the table below	No	No	1	0	4
static\_variation	integer	DNP3 command variation (). Supported variations depend on signal type and are provided in the table below.	No	No		0, 1, 2, 3, 4, 5, 6, 9, 10
event\_variation	integer	DNP3 command variation. Supported variations depend on signal type and are provided in the table below.	No	No		0	8
control\_code	string	DNP3 control model code of CROB signal. TripClose and Pulse control model requires PulseOn/off times to be set	Yes	Yes		LATCH, PULSE, TRIPCLOSE
pulse\_on\_time\_ms	integer	Pulse ON time in milliseconds, when using Pulse or TripClose control models must be set	Yes	Yes
pulse\_off\_time\_ms	integer	Pulse OFF time in milliseconds, when using Pulse or TripClose control models must be set	Yes	Yes
class\_num	integer	Class assignment of the signal.	No	No	0	0	3
operate\_type	integer	Default command behaviour. If selected: ”-1” - DirectOperateNoAck (FC=6), ”0” - DirectOperate (FC=5), "1" - SelectBeforeOperate (FC=3).	No	No	1	-1	1
job\_todo	string	The device status signal can be configured by providing one of the given values.	No	No		communication\_status, device\_running, device\_error, unknown\_error

##### Device status signals To configure any device status signal for the DNP3 protocol additional job\_todo column is required. For DNP3 master required parameters for status signal will be: **signal\_name,** **device\_alias, signal\_alias, index, signal\_type**, **event\_variation** (1,2 or 3) and **job\_todo**. There are 4 possible signals: communication\_status, device\_running, device\_error, uknown\_error. Each signal has 4 possible values and is based on the same logic. If the signal returns the value of 0, it means an unknown error has appeared, 1 – device or protocol connection is on and working properly, 2 – device is off or protocol is disconnected, 3 – error or service is down. ##### Command variations

Signal Type	Available Command Variation	Default Command Variation
Binary Output Command (Group12)	0, 1	1
Analog Output Command (Group41)	0, 1, 2, 3, 4	1

##### Static and Event variations

Signal Type	Available Variations	Default Variations
Binary	Static variation (Group1) 1, 2 Event variation (Group2) 1, 2, 3	Static variation 2 Event variation 1
Double Binary	Static variation (Group3) 2 Event variation (Group4) 1, 2, 3	Static variation 2 Event variation 1
Binary Output Status	Static variation (Group10) 1, 2 Event variation (Group11) 1, 2	Static variation 2 Event variation 1
Counter	Static variation (Group20) 1, 2, 5, 6 Event variation (Group22) 1, 2, 5, 6	Static variation 1 Event variation 1
Frozen Counter	Static variations (Group21) 1, 2, 5, 6, 9,10 Event variation (Group23) 1, 2, 5, 6	Static variation 1 Event variation 1
Analog	Static variation (Group30) 1, 2, 3, 4, 5, 6 Event variation (Group32) 1, 2, 3, 4, 5, 6, 7, 8	Static variation 1 Event variation 1
Analog Output Status	Static variation (Group40) 1, 2, 3, 4 Event variation (Group42) 1, 2, 3, 4, 5, 6, 7, 8	Static variation 1 Event variation 1
Time and Interval	Static variation (Group50) 1	Static variation 1
Octet String	Static variation (Group110) 0 Event variation (Group111) 0	Static variation 0 Event variation 0

#### Debugging the DNP3 Master service If the configuration for DNP3 devices is set up, a handler for the protocol will start automatically. If the configuration is missing or contains errors, the protocol will not start. It is done intentionally to decrease unnecessary memory usage. DNP3 protocol runs a service called **dnp3-master**. If DNP3 does not work properly (e.g. no communication between devices, data is corrupted, etc.), a user can launch a debug session from the command line interface and find out why the link is not functioning properly. To launch a debugging session, a user should stop the **dnp3-master** process and run the **dnp3-master** command with respective flags as in the table given below. Procedure for DNP3 Master protocol service debugging: - **Step 1**: Service must be stopped by entering the following command into the wcclite: **/etc/init.d/dnp3-master stop** - **Step 2**: After the service is stopped it must be started with the preferred configuration file (JSON files found in the /etc/ folder) and a debug level 7: **dnp3-master -c /etc/dnp3-master/dnp3master.json -d7**Additional output forming options described in the table below. - **Step 3**: Once the problem is diagnosed normal operations can be resumed with the following command: **/etc/init.d/dnp3-master start** dnp3-master command line debugging options

Option	Description
-h \[ –help \]	Display help information
-V \[ –version \]	Show version
-p \[ –port \]	Show output for one port only
-d <debug level>	Set debugging level
-c \[ –config \]	Config path
-a \[ –app \]	Show application layer data
–l \[ –link \]	Show link layer data
–t \[ –transport \]	Show transport layer data
-r \[ –redis \]	Show Redis messages
-R \[ –readyfile \]	Ready notification file

# 12.3 DNP 3.0 Slave Default group and variation sets are used to send static and event values. If master devices support different groups and variations, they can be adjusted in Excel configuration. WCC Lite-supported variations are provided in *Static and Event variations* and *Command variations.* ##### DNP3 Slave parameters for Devices tab

Parameter	Type	Description	Required		Default Value (when not specified)	Range
Parameter	Type	Description	TCP/ TLS	RTU	Default Value (when not specified)	Min	Max
name	string	User-friendly device name	Yes	Yes
description	string	Description of a device	No	No
device\_alias	string	Alphanumeric string to identify a device	Yes	Yes
enable	boolean	Enabling/disabling of a device	No	No	1	0	1
protocol	string	Protocol to be used.	Yes	Yes		dnp3 tcp slave dnp3 serial slave
mode	string	Choosing between TCP, TLS and SERIAL modes. If the protocol is provided DNP3 TCP mode defaults to tcp and if DNP3 serial is provided mode defaults to SERIAL	No	No	TCP or SERIAL	TCP, SERIAL, TLS
host	string	The IP address of the TCP slave device	Yes	-
bind\_address	string	The IP address of the network adapter used to connect to the slave device	No	-	0.0.0.0
port	integer	TCP communication port	No	-	20000
device	string	Communication port (”PORT1” or ”PORT2”)	-	Yes
baudrate	integer	Communication speed, bauds/s	-	No	9600	300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600,115200
databits	integer	Data bit count for communication	-	No	8	6	9
stopbits	integer	Stop bit count for communication	-	No	1	1	2
parity	string	Communication parity option	-	No	none	none, even, odd
flowcontrol	string	Communication device flow control option.	-	No	none	none
tls	boolean	Enable/disable the use of TLS	Yes (for TLS)	-	0	0	1
tls\_local\_certificate	string	Local certificate for TLS connection	Yes (for TLS)	-
tls\_peer\_certificate	string	Certificate authority file for TLS connection	No (for TLS)	-
tls\_private\_key	string	A file consisting of the private key for TLS connection	No (for TLS)	-
max\_tx\_frag\_size	integer	Maximum size of a received fragment.	No	No	2048	0	2048
destination\_address	integer	Address of a master station	No	No	1	0	65535
source\_address	integer	Address of a slave (local) station.	No	No	1	0	65535
unsol\_classes	string	Defines which classes will have unsolicited actions on startup. (Example: "1,3,2")	No	No	no class	1	3
time\_sync\_interval\_sec	integer, string	Periodic time sync interval in seconds. If 0 < - time syncs are forced and periodic. If = 0 - time syncs react to IIN bits from the slave. If < 0 - time syncs are disabled.	No	No	0	0
select\_ms	integer	Select command timeout. Valid for all signals.	No	No	10000
timeout\_ms	integer	Response timeout in milliseconds	No	No	2000
keep\_alive\_timeout	integer	The time interval for sending a keep-alive packet in milliseconds.	No	No	60

##### DNP3 Slave parameters for Signals tab

Parameter	Type	Description	Required		Default Value (when not specified)	Range
Parameter	Type	Description	TCP	RTU	Default Value (when not specified)	Min	Max
signal\_name	string	User-friendly signal name	Yes	Yes
device\_alias	string	Device alias from a Devices tab	Yes	Yes
signal\_alias	string	Unique alphanumeric name of the signal to be used	Yes	Yes
enable	boolean	Enabling/disabling of a device	No	No	1	0	1
index	integer	Index of a signal.	Yes	Yes		0	65535
log	boolean	Enable logging in the event log	No	No	0	0
deadband	integer, string	Deadband for Analog, Analog Output Status, Counter, and Frozen Counter signals.	No	No	0
signal\_type	string	DNP3 signal type. (case insensitive)	Yes	Yes		”binary”, ”doublebitbinary”, ”binaryoutputstatus”, ”binaryoutputcommand”, ”counter”, ”frozencounter”, ”analog”, ”analogoutputstatus”, ”analogoutputcommand”, ”timeandinterval”, ”octetstring”
command\_variation	integer	DNP3 command variation. Supported variations depend on signal type and are provided in the table below	No	No	1	0	4
static\_variation	integer	Override default signal’s static variation. Valid for Status mode signals.	No	No		0, 1, 2, 3, 4, 5, 6, 9, 10
event\_variation	integer	Override default signal’s event variation. Valid for Status mode signals.	No	No		0	8
control\_code	string	DNP3 control model code of CROB signal. TripClose and Pulse control model requires PulseOn/off times to be set.	Yes	Yes		LATCH, PULSE, TRIPCLOSE
pulse\_on\_time\_ms	integer	Pulse ON time in milliseconds, when using Pulse or TripClose control models must be set.	Yes	Yes
pulse\_off\_time\_ms	integer	Pulse OFF time in milliseconds, when using Pulse or TripClose control models must be set.	Yes	Yes
class\_num	integer	Class assignment of this signal.	No	No	0	0	3
operate\_type	integer	Default command behaviour. If selected: ”-1” - DirectOperateNoAck (FC=6), ”0” - DirectOperate (FC=5), "1" - SelectBeforeOperate (FC=3).	No	No	1	-1	1
job\_todo	string	The device status signal can be configured by providing one of the given values.	No	No		communication\_status, device\_running, device\_error, unknown\_error

##### Device status signals

To configure any device status signal for DNP3 protocol additional job\_todo column is required. For DNP3 slave required parameters for status signal will be: **signal\_name, device\_alias, signal\_alias, index, signal\_type**, **event\_variation** (1,2 or 3) and **job\_todo**. There are 4 possible signals: communication\_status, device\_running, device\_error, uknown\_error. Each signal has 4 possible values and is based on the same logic. If the signal returns the value of 0, it means an unknown error has appeared, 1 – device or protocol connection is on and working properly, 2 – device is off or protocol is disconnected, 3 – error or service is down. ##### Command variations

Signal Type	Available Command Variation	Default Command Variation
Binary Output Command (Group12)	0, 1	1
Analog Output Command (Group41)	0, 1, 2, 3, 4	1

##### Static and Event variations

Signal Type	Available Variations	Default Variations
Binary	Static variation (Group1) 1, 2 Event variation (Group2) 1, 2, 3	Static variation 2 Event variation 1
Double Binary	Static variation (Group3) 2 Event variation (Group4) 1, 2, 3	Static variation 2 Event variation 1
Binary Output Status	Static variation (Group10) 2 Event variation (Group11) 1, 2	Static variation 2 Event variation 1
Counter	Static variation (Group20) 1, 2, 5, 6 Event variation (Group22) 1, 2, 5, 6	Static variation 1 Event variation 1
Frozen Counter	Static variations (Group21) 1, 2, 5, 6, 9,10 Event variation (Group23) 1, 2, 5, 6	Static variation 1 Event variation 1
Analog	Static variation (Group30) 1, 2, 3, 4, 5, 6 Event variation (Group32) 1, 2, 3, 4, 5, 6, 7, 8	Static variation 1 Event variation 1
Analog Output Status	Static variation (Group40) 1, 2, 3, 4 Event variation (Group42) 1, 2, 3, 4, 5, 6, 7, 8	Static variation 1 Event variation 1
Time and Interval	Static variation (Group50) 1	Static variation 1
Octet String	Static variation (Group110) 0 Event variation (Group111) 0	Static variation 0 Event variation 0

#### Debugging the DNP3 Slave service If the configuration for DNP3 devices is set up, a handler for the protocol will start automatically. If the configuration is missing or contains errors, the protocol will not start. It is done intentionally to decrease unnecessary memory usage. DNP3 protocol runs a service called **dnp3-slave**. If DNP3 does not work properly (e.g. no communication between devices, data is corrupted, etc.), a user can launch a debug session from the command line interface and find out why the link is not functioning properly. To launch a debugging session, a user should stop the **dnp3-slave** process and run the **dnp3-slave** command with respective flags as in the table given below. Procedure for DNP3 Master protocol service debugging: - **Step 1**: Service must be stopped by entering the following command into the wcclite: **/etc/init.d/dnp3-slave stop** - **Step 2**: After the service is stopped it must be started with the preferred configuration file (JSON files found in the /etc/ folder) and a debug level 7: **dnp3-slave -c /etc/dnp3-slave/dnp3slave.json -d7** Additional output forming options described in the table below. - **Step 3**: Once the problem is diagnosed normal operations can be resumed with the following command: **/etc/init.d/dnp3-slave start** dnp3-slave command line debugging options

Option	Description
-h \[ –help \]	Display help information
-V \[ –version \]	Show version
-p \[ –port \]	Show output for one port only
-d <debug level>	Set debugging level
-c \[ –config \]	Config path
-a \[ –app \]	Show application layer data
–l \[ –link \]	Show link layer data
–t \[ –transport \]	Show transport layer data
-r \[ –redis \]	Show Redis messages
-R \[ –readyfile \]	Ready notification file