Mass Spectrometry: Remote control and collaboration

Mass Spectrometry: Remote Experimentation and Collaboration
University of Delaware

Overview	Laboratory		VNC-based solution
_____________Video-based descriptions___________
VNC-based solution		X meeting-based solution
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Coupling the mass spectrometer instrument and software
with VNC for remote collaboration

VNC (Virtual Network Computing) provided the client-server infrastructure that facilitated remote collaboration. This open source software employs a Remote Frame Buffer (RFB) protocol, thereby making it potentially applicable to all operating systems, windowing systems, and applications. The RFB protocol allowed us to have several, geographically distant, researchers concurrently

share the view and control of the mass spectrometer's X desktop; and
share the view of a separate video stream delivered by an internal CCD camera attached to the mass spectrometer's laser apparatus.

This section describes an actual demonstration performed with three collaborators:

one researcher in the Johnston mass spectrometry lab at UD, using a Sun workstation (Solaris 7);
a second researcher using a remote SGI Indy (IRIX 6.5); and
a third researcher using a remote PC (Windows 98).

A simulation of this scenario is illustrated in a video produced at the Internet Spring 2000 Joint Technical Meeting on March 28, 2000. (An earlier presentation using different collaborative tools was presented at Internet2 Awareness Day at the University of Delaware on January 19, 2000.)

The VNC components are pictured below:

A VNC server is run on one workstation in the laboratory to provide a virtual display (i.e., the Remote Frame Buffer or RFB). We run the VNC server on the same Sun workstation that is attached to the mass spectrometer, although the server could be run anywhere.
The X Windows client applications, supplied by the vendor (Bruker) and used for motor control, data acquisition, and data analysis, are also run on this Sun workstation. The VNC server acts as an X server to the mass spectrometer's X clients and draws each client application's output window in the Remote Frame Buffer.
A VNC viewer client is run on each collaborator's workstation, including the investigator's workstation in the laboratory. Each VNC viewer pulls its updates from the remote frame buffer, constantly refreshing the VNC window on each collaborator's monitor.
The internal CCD camera attached to the laser is connected to an Osprey-100 video-capture card. Sun Microsystem's SunVision software (specifically, Xil_display) sends the Osprey's digital video output at 10 frames/second to a second VNC server's RFB. (A successful alternative is to process the Osprey card's JPEG image output by Sun Microsystem's ShowMeTV software. ShowMeTV, run on the workstation attached to the instrument, multicasts RTP -- real time protocol -- packets at 10 frames/second. When the software is configured to send 8-bit, monochrome images, this generates more than 1 megabit/second in network traffic. Remote collaborators can run a Java Media Framework client to view the camera image.)

Operationally, the sharing session is started by running the VNC server in the lab. The remote participants can start their VNC viewer clients after learning what port and password the collaborator in the lab has chosen. Collaborators can join and drop out of the sharing sessions as they need to. The collaborators in the UD lab see the camera image on a separate Sony TV monitor. The others start a separate VNC viewer client to connect to the camera's VNC server, which uses a smaller desktop correctly sized for displaying the camera image.

Finally, we have used various ways to provide inter-collaborator communication, including Microsoft NetMeeting's chat and whiteboard, SunForum's similar capabilities, and conference phones. We are currently investigating implementation of H.323-based solutions for conversation among the participants.

Mass spectrometer and workstation in UD laboratory

On the laboratory workstation, the larger monitor displays the X Windows desktop. The workstation is running the X Windows vncview client and showing the VNC virtual desktop. The smaller monitor on the right displays the SVGA camera image that is captured through a direct cable connection to the internal CCD camera. There is also a laptop PC (not shown) which is running Microsoft NetMeeting.

Monitor screen of remote PC (Windows 98)

On each remote machine, the larger vncview window displays the X Windows desktop. The smaller window (upper-right corner) is a second vncview window displaying the camera image. On the lower-right is a chat session managed by Microsoft NetMeeting. NetMeeting is also being used to provide a point-to-point audio link between this PC and the laboratory laptop PC.

VNC viewer clients
All participants must run a VNC viewer client. There are currently three alternatives for the viewer.

The native vncview client, available from AT&T Research. This client is available for the following systems: Windows 9x, Sun (Solaris), MacOS, and generic X Windows (which we used for the SGI (IRIX) platform in our testing).
A Java applet viewer, included, for example, in JDK 1.1.x.
A Java-enabled web browser (e.g., Netscape 4.x, Internet Explorer 4.x). The Java applet is passed directly from the VNC server to the browser.

Mass spectrometer and workstation in UD laboratory
On the laboratory workstation, the larger monitor displays the X Windows desktop. The workstation is running the X Windows vncview client and showing the VNC virtual desktop. The smaller monitor on the right displays the SVGA camera image that is captured through a direct cable connection to the internal CCD camera. There is also a laptop PC (not shown) which is running Microsoft NetMeeting.
Monitor screen of remote PC (Windows 98)
On each remote machine, the larger vncview window displays the X Windows desktop. The smaller window (upper-right corner) is a second vncview window displaying the camera image. On the lower-right is a chat session managed by Microsoft NetMeeting. NetMeeting is also being used to provide a point-to-point audio link between this PC and the laboratory laptop PC.

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