Used by the world's top oil and gas companies

Protect Modbus Devices from Serial Attacks

PortBloque S
("port block")

PortBloque S is a specialized firewall that protects Modbus devices from serial attacks. It provides Modbus RTU/ASCII deep packet inspection (DPI), blocking everything that's harmful or unwanted. 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.

• DPI on Modbus RTU/ASCII
• Highly customizable
• 2 DB9 serial (Master, Slave)
• RS-232/422/485 software selectable
• 1 RJ-45 Ethernet (Web)
• 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 S
Serial Firewall with DPI on Modbus RTU/ASCII

$475.00 USD
Made in California

FREE technical support

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Protection against Internet attacks

Modbus security that's strictly serial.

Blocks function codes, registers, and 16-bit, 32-bit, and floating point values that you have not permitted to specific slave devices.

Blocks a command that repeats too soon to protect slave devices from malicious attacks, e.g., a servo attack (rpm).

Device ID

Function Code

Register

Value

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.

Intuitive.

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.

Select the Modbus function codes you want those devices to receive.

Enter permissible range of Modbus registers and values. Select 16-bit, 32-bit unsigned/signed or 32-bit floating point from a dropdown.

Floating point entry is straightforward.

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).

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.

Direct connect to Modbus slaves.

Protocols

Modbus RTU

Modbus ASCII

Ports

1 RJ-45 Ethernet
2 DB9 serial (RS-232/422/485 software selectable)

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PortBloque S
$475.00 USD
Typically ships in 5 days via UPS Ground

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