Test Sequencer for Ethernet devices

[MarcioCardoso]

We have used VISA > LabVIEW > TestStand to make our test sequences in a scenario which the DUTs were controlled through serial interface and the instruments through GPIB interface.
But currently, our DUTs have Ethernet interface and can be configured in a telnet session. Most of the Test Equipment have Ethernet interfaces too.

I would like start a discussion about if LabVIEW/TestStand is the best solution for IP/Ethernet DUTs and Instruments (traffic generator and analyzers).

IP test equipment vendors (e.g. Ixia, Spirent) have all tests procedures written in TCL (or other script language). And have their own test sequencer as the Test Composer/Conductor (Ixia) and iTest (Spirent).

Do you know them? What is your opinion about these other Test Sequencers?

Is the LabVIEW (VISA functions) the more suitable Program Language for command line interfaces like Telnet and SSH sessions?

Please tell us your opinion.

Best regards
Marcio

[Mark_Yedinak]

You are mixing concepts. VISA is simply an abstraction of the communication interface (RS-232, GPib, USB, TCP/IP) and has nothing to do with the language/protocol/command set used by the device. That is a completely different matter all together. Most devides that have multiple communication interfaces will use the same command set over all of the interfaces. This is where VISA comes in. You write your driver using VISA and it is trivial to communicate to the deivce over any of its supported interfaces. Now, what you communcicate is dependent on the device itself. Device manufactures are free to use whatever command set they like. There are some standards that define a common command set (such as IVI) that make it easier to communicate with similar devices from different manufactures provided they all support the same common command set. The device manufactures are under no obligation to do so though.

As for sequencers I would have to look at what capabilities are provided. From past experience most other test sequencers leave a lot to be desired.

[MarcioCardoso]

Sure, nice point and explanation, VISA is great in abstracting the interface type (serial, GPIB, USB and TCP/IP).

And returning to TCP/IP devices, the LabVIEW Internet Toolkit is an additional package ($ 550). It can be used for telnet sessions but there is no SSH protocol functions.

I've used TestStand and really I liked it. But the company I work for just bought an Ethernet tester and is going to use Test Conductor. I saw some introduction videos about it and it seems be at least as good as TestStand.

Please take a look in Test Conductor, iTest and others, if someone else have more suggestions.

[PhillipBrooks]

I've never used it, but TestStand does include a TCL Adapter. If you need to use a secure connection to your UUTs,  you might be able to script that using TCL and Plink. 

The LabVIEW Internet Toolkit is somewhat limited (old). That said, it works. We've used it for 10+ years now and couldn't run tests without it. I do really wish that this Idea Exchange entry would change from New to In Development though...

As for Test Conductor, it appears to me after a quick look that it is more of a system level test/validation environment. My only experience with TestStand is as a manufacturing production tool. 

If your company has already selected/purchased Test Conductor, I would also check on the Ixia forums to find out what sort of options are available for interfacing to non-networked test equipment.

[MarcioCardoso]

Good, TestStand has the TCL adapter.

However TCL scripts can be run in other Sequencers. TestStand is the natural choise if you program teststeps in LabVIEW.

LabVIEW executing (System Exec.vi) PuTTY (Plink) in very bad because you are not able to return data for each command sent and than make decisions in LabVIEW to send others PuTTY commands again. You have to execute the whole script, or you have to login each time a command is sent.

Thanks for your suggestion.