RTX Virtual Network Add-On

The RTX Virtual Network provides a virtual point-to-point connection between Windows and RTX that emulates a local area network connection on a system. The RTX Virtual Network Add-On allows developers the flexibility to use socket communication between processes on the same system with no additional hardware. The virtual network also allows for easy porting of multiple system applications to run on one system with no code changes.

This installation consists of a Windows Virtual RTX Ethernet Adapter and a RTX Virtual NIC which is used by the RT-TCP/IP Stack.

Typical Network Connection

RTX to Windows Virtual Network Connection

Topics:

Configuring the RTX Virtual Network Add-On
Testing your Configuration
Known Issues

Configuring the RTX Virtual Network Add-On

If installed, the RtVirtual NIC driver is one of the drivers that is automatically registered upon enabling or disabling the RT-TCP/IP stack.

In RTX, you must configure values for the RTX Virtual NIC Driver in the RT-TCP/IP Stack RtxTcpIp.ini file.
In Windows, you must configure the Windows Virtual RTX Ethernet Adapter through Windows Device Manager.

For more information, see RTX TCP/IP Stack and Driver Configuration. For a complete list of configurable parameters, see NIC Driver Section.

Configure the RTX Virtual NIC Driver

In RTX, you must specify configuration settings for the RTX Virtual NIC driver in the RT-TCP/IP Stack. To do this, follow the steps below.

Steps:

Navigate to the RTX installation directory (C:\Program Files\IntervalZero\RTX by default).
In the \bin directory, open the file RtxTcpIp.ini.

NOTE: If you need help locating this file, you can find its current location by looking at the TCP/IP tab of the RTX Properties control panel.

Add/set these configuration parameters in the file RtxTcpIp.ini. Specify required values as related to your application.

Under [TCP/IP]:

NumOfInterfaces

Under [rtndn]

Driver=RtVirtualNic
IPAddr
Netmask

Save and close the file.

Example:

Below is an example of a RtxTcpIp.ini file. Highlighted values are required for configuration of the RTX Virtual NIC Driver. You must specify required values as related to your application.

	[TCP/IP]
	MemoryInK=256
	TickInterval=200
	MaxSockets=30
	TimerPriority=66
	NumStartupEvents=20
	NumOfInterfaces=1
			
	[rtnd0]
	Driver=RtVirtualNic      
	IPAddr=10.10.1.5       
	Netmask=255.255.255.0
	InterruptPriority=64
	ReceivePriority=63
	TransmitPriority=12
	RxFifoSize=32
	TxFifoSize=32
	EA=1234567890AB
	NumXmitBuffers=8

IMPORTANT! The Subnet mask you specify in the RtxTcpIp.ini file must match the Subnet mask specified in Windows (see below).

Configure the Windows Virtual RTX Ethernet Adapter

Next, configure values for the Virtual RTX Ethernet Adapter through Windows Device Manager.

Steps:

Configure the IP address and Subnet mask for the Virtual RTX Ethernet Adapter in Windows:

Windows 7: Start > Control Panel > Network and Sharing Center > Local Area Connection > Properties > Internet Protocol Version 4 (TCP/IPv4) > Properties > Use the following IP address

NOTE: Leave the Default gateway and DNS fields empty.

IMPORTANT! The Subnet mask you specify in Windows must match the Subnet mask specified in the RtxTcpIp.ini file.

Open Windows Device Manager:

Windows 7: Start > Control Panel > Hardware and Sound > Device Manager

Expand the Network adapters branch.
Right-click on Windows Virtual RTX Ethernet Adapter and select Properties.

The Properties dialog appears. In the Advanced tab, configure the following properties:

IMPORTANT! Make sure the RTX Subsystem is stopped before you change configuration options for the RTX Virtual Network.

Property	Description
Jumbo Packet	Enables the frame sizes larger than standard Ethernet MTU. The identical value must be set in the `RtxTcpIp.ini` file. Note: If you use multiple RTX NICs (one physical and one virtual), and enable Jumbo Packets with an MTU value of 16114, an exception may occur. To avoid this, increase the `MemoryInk` value in the `RtxTcpIp.ini` file.
RTX EA	Not supported in this release.
RTX Location	Not supported in this release.

Property

Description

Jumbo Packet

Enables the frame sizes larger than standard Ethernet MTU. The identical value must be set in the RtxTcpIp.ini file.

Note: If you use multiple RTX NICs (one physical and one virtual), and enable Jumbo Packets with an MTU value of 16114, an exception may occur. To avoid this, increase the MemoryInk value in the RtxTcpIp.ini file.

RTX EA

Not supported in this release.

RTX Location

Not supported in this release.

Testing your Configuration

To test that the RTX Virtual Network is configured properly, follow the steps below:

Steps:

Configure the RTX Virtual NIC Driver (RTX) and the Windows Virtual RTX Ethernet Adapter (Windows) following the instructions above.
Start the RTSS subsystem.
Obtain the static IP address for the RTX Virtual NIC Driver from the RtxTcpIp.ini file.
Use the Windows ping utility to ping the RTX Virtual NIC Driver at the IP address from Step 3.
Use RtssPing to ping the Virtual RTX Ethernet Adapter at the IP address specified in Step 4.

IMPORTANT! You must not hibernate or suspend the system when the RTX Virtual Network is in use.

Known Issues

Wireshark displays the RTX Virtual Network incorrectly as RTX Virtual Network Adapter. (RTX-1230)
A Blue Screen occurs when you attempt to change options in the Properties dialog for the RTX Virtual Network via Windows Device Manager while the RTX Subsystem is running. (RTX-1229)
To build this driver with versions of RTX prior to RTX 2012, you must disable the post-build step to timestamp the RTSS binary in RtVirtualNic.vcxproj.