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Protect Modbus Slave Devices from Internet Attacks

PortBloque E
("port block")

PortBloque E is a specialized firewall that protects serial Modbus devices from Internet attacks. It combines firewall operation and Modbus TCP/UDP deep packet inspection (DPI) to block everything that's unwanted or harmful. The simple web interface makes setup easy. Operators can control Modbus traffic by slave IDs and function codes, and block a command that repeats too soon, e.g., to prevent a servo attack (rpm). Additionally, operators can define a permissible range of slave registers and values to prevent malicious memory access. The integrated Modbus IP-serial converter offers the flexibility and convenience of Internet enabling serial devices.

• DPI on Modbus TCP/UDP 
• Access control list
• Stealth mode to hide network
• Highly customizable 
• Modbus IP-serial conversion
• 1 RJ-45 Ethernet (Web)
• 1 DB9 serial slave (RS-232)
• 1 DB9 serial console (RS-232)
• Small size approx: 4 x 3 x 1 in
• 0 to 85°C (32 to 185°F)
• Durable metal housing
• Ships with external 5VDC (2A) power supply

Download the Datasheet
PortBloque E
Ethernet Firewall with DPI on Modbus TCP/UDP

$495.00 USD

Made in California

FREE technical support

Protection against
serial attacks

Packed with Modbus security features.

Blocks function codes, registers, and values that you have not permitted to specific slave devices.

Blocks a command that repeats too soon to protect slave devices.

Blocks IP packets that are not expected (per origin, destination, protocol, and port).

Ignores scans/probes from intruders to make the Modbus network virtually invisible to hackers.

Device ID
Function Code
Detailed control of Modbus.

You can select the types of function codes that specific slaves can receive and define accessible read/write ranges for registers and values.

The simple web interface provides detailed control over Modbus traffic. 
Take a look at how easy it is.
Enter the Modbus device IDs of serial slaves you want to protect.
Security - Modbus device IDs
Select the Modbus function codes you want those devices to receive.
Security - Modbus function codes
You can also enter Modbus register and value ranges.
Security - Modbus addresses
And enter the amount of time to wait before a particular Modbus command can be repeated to prevent malicious attacks, e.g., a servo attack (rpm).
Security - Time between Modbus command
You can also enter non-standard Modbus function codes that are in use by your plant. Examples of customer-entered numerical codes and names are shown below.   
Security - custom codes
Direct connect to Modbus slaves. 
Built-in Modbus IP-serial converter  
Ethernet: Modbus TCP/UDP 
Ethernet: Modbus RTU over TCP/UDP
Ethernet: Modbus ASCII over TCP/UDP
Serial: Modbus RTU
Serial: Modbus ASCII

1 RJ-45 Ethernet
1 DB9 serial slave (RS-232)
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PortBloque E
$495.00 USD
Typically ships in 5 days via UPS Ground

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