Is there a quick setup guide for the AlphaRNG device?

The AlphaRNG quick start guide can be found on this page.

Can I use the AlphaRNG device with Virtual Machines?

Yes, AlphaRNG works with Linux, macOS, Windows 10/11 (64-bit), and Windows Server 2016/2019 (64-bit), and runs in virtual machines using software such as VMware, Oracle VirtualBox, and Parallels Desktop.

Why is my throughput lower than the advertised speed?

AlphaRNG can deliver up to 199 Mbps in non-secure mode. When the encrypted, authenticated session is enabled (the default), throughput depends on the cipher and MAC you choose, ranging from about 30 Mbps with HMAC-MD5 down to 4.6 Mbps with AES-256-GCM. This is the expected tradeoff for an encrypted, tamper-evident USB channel, not a defect. Applications that do not require an encrypted channel can use non-secure mode for the full 199 Mbps.

How can I integrate the AlphaRNG device with my software application projects?

Through the provided Software API and utilities, AlphaRNG devices can be used with applications built for Linux, FreeBSD, macOS, or Windows, using C or C++. On Windows, a DLL and shared entropy-server are also included, allowing integration from C#, VB, Excel, MATLAB, Delphi, and other languages that can call a Windows DLL, with multiple applications able to access the device concurrently.

Can I use AlphaRNG without linking the API into my application?

Yes, on Linux you can load the alrandom kernel module included in the software kit. Once loaded, random bytes are available directly through the /dev/alrandom character device, so any tool that can read a file can use it, for example dd if=/dev/alrandom of=/dev/null bs=100000 count=10. This is also a convenient way to feed the Linux kernel’s own entropy pool.

I am getting a “could not lock device” or permission error on Linux. What do I do?

Two common causes:

  • Permissions. Install the udev rules file included in the software kit (85-alpharng-usb-access.rules) so the device is accessible without root privileges.
  • Device already in use. AlphaRNG allows only one active connection at a time. If another process, or a previous session that did not close cleanly, still holds the device open, new connection attempts will fail until it is released.

My secure session fails to establish. What should I check?

Verify you are using the RSA public key file specific to your device, provided at the factory. Each AlphaRNG device is provisioned with its own unique public key, and for best security you should use that factory-provided key rather than the default. A mismatched or incorrect key file will cause the secure session to fail to establish.

Why does my AlphaRNG device perform slower than expected?

There could be multiple reasons:

  • An old computer system with a slow CPU will decrease download speed, and will especially affect throughput in secure mode, since AES/RSA encryption runs on the host CPU.
  • The AlphaRNG device may have been plugged into an old USB 1.1 port. For the best results, use a USB 2.0 or later port.
  • On some Linux based operating systems, the CPU may be running at lower speeds to preserve power usage. Use the lscpu command to check current CPU speed.
  • An operating system that runs in a Virtual Machine may affect overall system performance. If your VM is configured with a USB 2.0 (EHCI) controller, switching to a USB 3.0 (xHCI) controller can noticeably improve throughput.