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LabVIEW needs native SSH and SFTP connection support. 

 

In the past, LabVIEW users have had to rely on third party applications like PuTTY or ExtraPuTTY to do very basic Linux/Unix secure shell operationsNot only does it add an extra layer of complexity to the code but it is also quite inflexibleIncreasing interoperability requirements of present day (and future) computer systems rely heavily on terminal services with a vast percentage of those being SSH basedIn the past 5 years I have needed to use SSH type connections more and more inside of LabVIEW, I do not see it ending anytime soon and I know I am not alone.

 

An SSH connection could be managed in much the same manor as the current VISA and TelNet connection are managedAn example of some of the tools could look something like the below image and could come standard or part of the Internet Connectivity Toolkit.

 

2010-06-03_LVIE_SSH.png

The web format wars are over, and the plug-ins have lost.  Microsoft has relented and will support HTML5 and SVG in IE9, and has admitted that Silverlight's role will change to that of a Windows phone development platform.  Silverlight support on iPhone/iPad/Andoid/Chrome OS will likely never be fully formed, and will wither on the vine. 

 

New javascript/ecmascript engines that are much faster, and make use of multicore environments have arrived and work well.  The addiition of WebSockets means your browser can now open a tcp/ip socket.  I have done this, as I am sure others have, as well.  Drop an old-fashioned tcp/ip listener into your diagram, return the WebSocket handshake, and presto: you can now stream data directly to/from your browser.  WebSockets provides an "onmessage" event handler function which you can define.  Combine this with the SVG DOM, and you can transform SVG elements until your heart is content.  Two-way streaming of data between your browser and plain-old tcp/ip?  Goodbye web services, we knew you well. Good riddance, plugins.

 

I have built my own SVG UI objects using Inkscape (free), and wrote a script (notepad/Inkscape script editor, also free) to handle WebSockets communication without a gateway.  I have a simple LV class built on the TCP/IP functions that will stream data to/from a browser which is pointing to an SVG "webpanel" that I also built using Inkscape.  So far I have a simple waveform graph, buttons, LED's, progress bars, etc.  I have tested my Inkscape webpanels in Firefox 4.0 Beta and Google Chrome 9 and it works like a champ, and is very fast.  The old-fashioned LV webserver will serve up SVG files with the addition of a mime type. 

 

Screenshot_5.png

 

 

An alternative to SVG is the HTML5 <canvas> tag, which allows the rendering of graphics drawn using java/ecma script.  There is a free-for-personal-use script library called RGraph Library that you can download with lots of example code.  Here is RGraph/LabVIEW in action in Chrome 9:

 

 

Screenshot_7.png

 

 

So what is my idea?  

 

0. Ditch Silverlight.

 

1. Convert all of the nice-looking UI panel objects in the Web UI Builder from Microsoft XAML to SVG and distribute them with the  LabVIEW professional development license.  I am programmer first, and I admit my web panel objects don't look too good.

 

2. Design a script library for handling WebSockets communcation (or add native support for WebSockets to the Shared Variable Engine) and manipulating/updating the SVG UI objects from streamed WebSockets data.  Make this library open source.

 

3. Create a standard open protocol for streaming LabVIEW data that sits on top of WebSockets and is free and open.

 

4. Publish documentation for the SVG UI elements so users and thrid parties can create new UI objects.  Make use of the creativity of the community at large!

 

5. Modernize the Web Publishing Tool so that it will optionally output an HTML5 and/or SVG document that accepts streaming I/O from WebSockets.  The user could choose from compatible SVG elements to use in place of front panel elements on the VI being published.

 

6. Create a Web UI SVG element exchange for registered NI users to upload/download elements for free.

 

7.  Work toward the long term goal of adding SVG Import/Export to the control editor (with better editing tools), or make the CTL format of custom controls SVG/XML.

 

With the IPv4 address pool quickly getting used up I think we need to have native support for IPv6 connections in LabVIEW.

LabVIEW currently porvides TCP and UDP primatives. It would be nice if it had a PING primative as well.

LabVIEW needs native SSL/TLS support for the TCP primitives. The HTTP functions support it (see \vi.lib\httpClient\ConfigSSL.vi). There are several great LabVIEW native MQTT libraries that could be commercially usable if there was native SSL/TLS support. Not having this functionality for the TCP primitives makes LabVIEW a poor choice for an IoT platform.

I would like to see more native support for compression and encryption/hash algorithms.

 

When it comes to compression and encryption. We are very much the poor relations to other languages that have a plethora of source and examples for SHA1, DES, 3DES, Blowfish, HMAC, Ryjindel, AES (encryption) and LZO, LZMA, LZW, GZip, JPEG2000 (compression) to name but a few.

 

Apart from "Zip" (which can only be used on files) and "twofish" (which is hardly an industry standard because of security concerns) we have very little choice but to use DLLs and SOs meaning our applications violate one of the biggest reasons for using LabView........cross-platform. We have very little in our tool-kit to make efficient and secure network applications for example. Especially if we are required to interface to existing systems that ave used these technologies for many years.

 

We cannot even write applications to access Twitter any more!

 

With the introduction of "Stream" prototypes in the new LV2010, it is essential to have these tools in our palettes.

According to the increasing number of questions about this communication protocol, it would be time to rewrite the MODBUS library. I also suggest to add it to the NI device drivers installer.

 

This could be the place to list the expected modifications. Some comments and bugs are already listed in above linked page.

The Run Method is pretty much the only option we have in LabVIEW to scale an application dynamically by instantiating new VIs - but there is one big catch - for some reason it requires the unser interface to be idle(!).

 

Related methods like setting control values e.g. do not have this requirement so they do not pose a problem - but the main method for dynamic instantiation does - and can be blocked by something as simple as a user that opens the calendar view of a date and time control (which of course never should do this either, but that's another issue/idea).

 

Personally I use the run method to create new trend windows (you never know how many trends a user wants to see at the same time), create session handlers for remote clients etc. The times it is used to actually create user interfaces it is not a big problem that the run method is in the user interface thread, but for session handlers and other things that needs to be created in the background based on requests from the outside? A HUGE issue.

In the current LabVIEW XML Schema, the flatten to XML string supports variants, but not variant attributes (and by extension waveform attributes as well). This is unfortunate as variant attributes remain one of the best ways of implementing a dictionary type data structure and they are also a useful way of adding additional metadata to waveform signals. In both cases, serializing the attributes to XML strings properly would greatly facilitate data exchange with non LabVIEW code.

There are a plethora of timestamp formats used by various operating systems and applications. The 1588 internet time protocol itself lists several. Windows is different from various flavors of Linux, and Excel is very different from about all of them. Then there are the details of daylight savings time, leap years, etc. LabVIEW contains all the tools to convert from one of these formats to another, but getting it right can be difficult. I propose a simple primitive to do this conversion. It would need to be polymorphic to handle the different data types that timestamps can take. This should only handle numeric data types, such as the numeric Excel timestamp (a double) or a Linux timestamp (an integer). Text-based timestamps are already handled fairly well. Inputs would be timestamp, input format type, output format type, and error. Outputs would be resultant format and error.

LabVIEW's HTTP Request client currently does not support the PATCH method. This method is becoming increasingly more popular within RESTful API's and has been an officially recognized verb since 2010 (RFC 5789). It should be fairly simple to integrate, since LabVIEW runs cURL under the hood and cURL implements it with curl --request PATCH

 

When you are generating data from a source and sending it across a TCP connection, it would be useful to be able to get information about when packets are being dropped and resent in the connection. If lots of drops are being detected, a program might be able to slow down the data acquisition or take other action to reduce the amount of information being transmitted to account for the lower bandwidth connection. Currently there is no way to get this information from the TCP primitives.

 

This idea comes out of the Certified LabVIEW Architect Summit held yesterday and today at NI headquarters in Austin, TX.

 

It would be nice if we had the option to terminate a TCP Read on a single character rather than only a CR/LF. There are many times where you would terminate a read on some end character such as a 0x03 (ETX). In order to accomplish this now we need to have a tight loop which reads from the connection a single byte at a time. Even better would be if we could specify a string as the termination sequence. However, I would be happy with a single character option.

When using the Sahred variable (SV) with "Bind to source", the SV uses the datatype of its source.

If you are using the datatype "double" you can see all fractional digits.

That doesn't make sense all the time - e.g. if you want to display temperature values.

 

Our idea is to give the user the opportunity of controlling the number of digit of precision.

 

Digits of precision.jpg

 

Thanks

When using the LabVIEW Internet Toolkit FTP library to transfer large files, there is no way to determine the progress.

 

I propose a notifier be added to the FTP Registry object data. This notifier would be updated by the low level TCP Read Stream and TCP Write Stream vis and monitored by a UI to display progress of the transfer.

 

See this NI Forum post...

 

FTP transfer progress bar

http://forums.ni.com/ni/board/message?board.id=170&message.id=470946 

 

 

 

 

 Connecting to remote panels using LabVIEW is difficult if private networks, local private and external public IPs (under NAT), and firewalls, etc. are involved. It requires significant knowledge as well as external networking configurations (port forwarding, etc.), and possibly admin privileges to modify those.

 

There are plenty of companies that have found a way around all this. The prime example is chrome remote desktop, which seamlessly works even if target computers are in hidden locations on private networks, as long as each machine can access the internet with an outgoing UDP connection. The way I understand it, each computer registers with the Google server, which in turn patches the two outgoing connections together in a way that both will communicate directly afterwards. All traffic tunnels inside the plain Google chat protocol (udp based). Similar mechanisms have been developed for security systems (example) and many more.

 

Since the bulk of the traffic is directly between the endpoints, the traffic load on the external connection management server is very minimal. It simply keeps an updated list of active nodes and handles the patching if requested.

 

I envision a very similar mechanism where LabVIEW users can associate all their applications and distributed computers with a given user ID (e.g. ni profile), and, at all times be able to get a list of all currently running remote systems published under that user ID. If we want to connect to one of them, the connection server would patch things together without the need of any networking configuration. Optionally, users could publish any given panel under a public key, that can be distributed to allow public connections by any other LabVIEW user.

 

This is a very general idea. Details of the best implementation would need to be worked out. Thanks for voting!

 

I would like to see the functionality of the TCP and UDP primitives expanded to include more state information, better control of the connections and the capability to receive events for the connection.

 

Items that I can see which would be helpful would include the following:

  1. Ability to enable/disable the Nagling algorithm.
  2. Ability to abort a TCP connection with a TCP-RST. (The wire is there on the TCP-Close primitive but it doesn't do anything)
  3. Ability to receive an event when data is present.
  4. Ability to receive an event when the data has actually be put on the wire. (Currently the write VIs return as soon as the data is buffered. There is no ability to have the application wait until the data is actually delivered.)
  5. More access to the IOCTLs that are available on a socket connection that a programmer has access to via Linux or Windows socket libraries.

Several users of XNET miss an important function from the driver: to read signals' logical value from the database.

For example, the value of 1 means 'Initialized', 0 means 'not initialized'. We would like to read those strings.

 

See this thread.

In Visual Studio you have XML Schema tools etc. It is a breeze to e.g. populate a drop down menu based on XML from a web service, and my first thought when I see it in action is - why do we not have this at our fingertips in LabVIEW already? LabVIEW could have made it simple to create schemas, generate flexible XML etc. You could have wizards that helped you, and cluster to xml conversion like in EasyXML from JKI - and it should all feel fully integrated (toolkits are OK, but this really needs to have native support).

 

I am currently developing a web service in LabVIEW and the first thing I had to do was to abandon the few in-built XML functions and write my own serialization code (using terminal mode for the web service gave you XML without proper headers, and the in-built flatten to XML outputs XML is impractical in use). Once I have serialized a text table e.g. and published it - using that table feels incredibly easy in Visual Studio (add data source-> input web address etc.) , it would be much more difficult to do the same in LV.

 

I think NI should make a big leap in the use of web technology. The RESTful web service functionality was a great addition, but the doumentation is non-existing, and we should have come much further by now. I know there are some cool experiments going on with web based GUI editors, but LabVIEW 2010 was just released with very little news on this front so forgive me if I rant a bit...Smiley Sad

With the advent of the IoT and the growing need to synchronize automation applications  and other TSN (Time Sensitive Networking) use cases UTC (Coordinated Universal Time) is becoming more and more problematic.  Currently, there are 37 seconds not accounted for in the TimeStamp Which is stored in UTC.  The current I64 portion of the timestamp datatype that holds number of seconds elapsed since 0:00:00 Dec 31, 1900 GMT is simply ignoring Leap Seconds.  This is consistent with most modern programming languages and is not a flaw of LabVIEW per se but isn't quite good enough for where the future is heading   In fact, there is a joint IERS/IEEE working group on TSN 

 

Enter TAI or International Atomic Time: TAI has the advantage of being contiguous and is based on the SI second making it ideal for IA applications.  Unfortunately, a LabVIEW Timestamp cannot be formated in TAI.   Entering a time of 23:59:60 31 Dec 2016, a real second that did ocurr, is not allowed.  Currently IERS Bulletin C is published to Give the current UTC-TAI offset but, required extensive code to implement the lookup and well, the text.text just won't display properly in a %<>T or %^<>T (local abs time container and UTC Abs time container)  We need a %#<>T TAI time container format specifier. (Or soon will!)