Hi everybody,

Can anybody recommend an AntiVirus that is appropriate for a realtime control system based on Windows XP SP2, TwinCAT I/O, a VB6 program and Profibus communication to a PLC?

In addition to above description of the system I should say that in this system an IPC connected as a slave profibus node to the PLC (Siemens 315-2DP). The VB6 program communicate to PLC via TwinCat I/O by using ADS.ocx controls.
The VB program sends some commands via IPC serial port (Com1) to other devices.

An important thing that should consider in selecting antivirus is that the VB program send serial port commands based on an acuurate time delays (in the one mili-second range). Actually the VB program communicate with an ECU system via K-Line bus with KWP2000 protocol. I'm afraid about the delays may come to the system by using antivirus.

Please let me know your experience of using antivirus programs in TwinCAT control systems and your antivirus recommendation for this case.

Many thanks in advance for your help.

Best regards,
Najafabadi

 

MS Windows is not a real time operating system. You can't guaranty your one millisecond timing now. How critical is it to have accurate timing 100% of the time?

However, any anti-virus scanner is by it's nature a very intrusive program that can have unexpected major effects on the PC. Also, you have to update the anti-virus system constantly if it is to be effective, and it is not at all unusual for bugs in those updates to cause serious problems for the operating system. Past experience with a particular anti-virus scanner is no guaranty of future performance.

In other words, if the side effects of an anti-virus scanner are a legitimate concern, then that suggests that you can't use an anti-virus scanner.

As another point, an anti-virus scanner without a subscription to anti-virus updates, and a network connection (either to the internet or to a business's own distribution repositories) is not much use. Viruses change all the time, and the anti-virus scanner software has to be kept up to date on a real-time basis to do you any good. Who is going to be maintaining the updates and how will that connection to the outside world be provided?

The alternatives seem to be to either a) not install AV software and hope that nothing happens, or b) to port your software over to another operating system. Viruses, spyware, worms, trojans, etc. are almost exclusively an MS Windows phenomenon (with a few on Mac OS/X, and virtually none anywhere else).