Advanced Software and Control for Astronomy Astronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006 1 Optimizing interactive performance for long- distance remote observing Robert Kibrick and Steven L. Allen University of California Observatories / Lick Observatory Al Conrad and Gregory D. Wirth W.M. Keck Observatory Advanced Software and Control for Astronomy Orlando, Florida May 26, 2006
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Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Optimizing interactive performance for long-distance remote observing
Robert Kibrick and Steven L. Allen
University of California Observatories / Lick Observatory
Al Conrad and Gregory D. Wirth
W.M. Keck Observatory
Advanced Software and Control for Astronomy
Orlando, Florida May 26, 2006
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Remote observing with the Keck Telescopes – The first 10 years
Robert Kibrick and Steven L. Allen
University of California Observatories / Lick Observatory
Al Conrad and Gregory D. Wirth
W.M. Keck Observatory
Advanced Software and Control for Astronomy
Orlando, Florida May 26, 2006
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Overview of Presentation
• Background– Historical evolution of Keck remote observing– The Keck Remote Observing Model– Remote observing from Waimea and California
• Redirecting displays– Using X protocol– Using VNC protocol
• Advantages and disadvantages of using VNC• Current usage patterns• Scheduling issues• Future plans
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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The Keck Telescopes
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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From 1993 to 1995, all Keck observing was done at the summit
Observers at the summit work remotely from control rooms located adjacent to the telescope domes
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Conducting observations involves coordinated effort by 3 groups
• Telescope operator (observing assistant)–Responsible for telescope safety & operation–Keck employee; normally works at summit
• Instrument scientist (support astronomer)–Expert in operation of specific instruments–Keck employee; works at summit or Waimea
• Observers–Select objects and conduct observations–Employed by Caltech, UC, NASA, UH, or other
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Keck 2 Control Room at the Mauna Kea Summit
Telescope operator, instrument scientist, and observers work side by side, each at their own remote X Display
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Observing at the Mauna Kea summit is both difficult and risky
•Oxygen is only 60% of that at sea level
•Lack of oxygen reduces alertness
•Observing efficiency significantly impaired
•Altitude sickness afflicts some observers
•Some are not even permitted on summit:
–Pregnant women
–Those with heart or lung problems
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Keck 2 Remote Control Room at the Keck Headquarters in Waimea
Observer and instrument scientist in Waimea use video conferencing system to interact with telescope operator at the summit
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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The initial model for Keck Remote Observing
All observing applications run on summit control computers
All displays are re-directed to display hosts at each site
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Why did Keck initially choose this approach?
•Operational Simplicity
•Operational control software runs only at the summit
•All users run identical software on same computer
•Simplifies management at each site
•Allowed us to focus on commonality
•Different sites / teams developed instrument software
•Large variety of languages and protocols were used
•BUT: all instruments used X-based GUIs
•Legacy GUI applications (e.g., not web-based)
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Initiative to support remote observing from Keck Headquarters
• 1995: Remote control rooms built at Keck HQ
• 1996: Remote observing with Keck 1 begins
• 1997: >50% of Keck 1 observing done remotely
• 1999: remote observing >90% for Keck 1 and 2
• 2000: remote observing became the default mode
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Remote Observing from Waimea is not cost effective for short runs
•Round trip travel time is 2 days
•Travel costs > $1,000 U.S. per observer
•About 50% of runs are for 1 night or less
•Cost / run is very high for such short runs
•Such costs limit student participation
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Explore the feasibility of remote observing from the mainland
•Initial experiments 1996-2000–Caltech experiments with NASA satellite–UCSC experiments with Internet-2 link
•2000-2001 ISDN fallback tests at UCSC
•2001 ISDN router installed at Keck summit
•2001 Prototype facility at UCSC online
•UCSC facility used as model for other sites
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Location First Use
Remote Ops 1, Waimea, HI 1996
Remote Ops 2, Waimea, HI 1997
UC Santa Cruz, CA 2001
UC San Diego, CA 2003
Caltech, Pasadena, CA 2004
UC Berkeley/LBNL, CA 2005
UC Los Angeles, CA 2006
Keck Observatory remote observing sites
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Global view of multi-site topology
Type your question here, and then click Search.
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Santa Cruz Remote Observing Facility
Remote observer in California uses video conferencing system to interact with colleague in Waimea
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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UC Los Angeles (UCLA) remote observing facility
The newest Keck remote observing facility in CA
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UC Los Angeles (UCLA) remote observing facility
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Initial efforts to extend remote observing model to the mainland
Type your question here, and then click Search.
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Limitations of using X to redirect displays to the mainland
• Sluggish performance for some operations
– very slow application startup compared to Waimea
– slow creation of new windows and pulldown menus
– guider display update rate is too low• Inability to share “single-user” applications
– various data reduction packages• Some applications sensitive to inter-site font variations
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Virtual Network Computing (VNC)
• VNC server provides shareable virtual desktop
• VNC clients (viewer) offer remote access to that desktop• All clients share that desktop (application sharing)• All state is retained in the server, none in the clients• Clients can connect/disconnect without affecting session• VNC protocol works at the framebuffer level• VNC available on most OS / windowing systems
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Redirecting displays to remote sites using VNC protocol & ssh
An ssh port-forwarding tunnel is used to relay VNC protocol packets and authentication across network firewalls to the remote site.
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Benefits of using VNC
• Single-user applications can be shared between sites– Shared desktop promotes training and collaboration– All sites have identical view and see each others actions– Shared desktop persists even if remote VNC client crashes– Optional read-only sharing for “look but don’t touch”
• X clients connect to a local X server (short RTTs)– X client applications run on control computer at summit– VNC server runs on computer at the summit– X clients see the VNC server as their local X server
• Speeds up client functions that require multiple X transactions– Application startup and initial painting of displays– Creation of pop-up windows and sub-panels– Instantiation of pull-down menus– Loading of fonts
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Disadvantages of using VNC
• Some operations are slower across a low bandwidth link– iconify / de-iconify operations are very slow (no backing store)– color map scrolling is slower than under a native X connection
• Ssh has no built-in capability for forwarding VNC packets– must start port-forwarding tunnel (ssh –L) before VNC viewer
• Shared desktop is sometimes a source of user confusion– Keyboard / mouse input from all connected clients are merged– Users at different sites could type or move mouse at same time– Potential for multiple users to create conflicting inputs–These conflicts can be reduced via use of '-viewonly' mode
• ADVANTAGES OF VNC OUTWEIGH THE DISADVANTAGES
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•X Visuals:–Depth: 8-, 16-, and 24-bit–PseudoColor, StaticColor, and TrueColor–Many X servers support multiple X visuals–VNC server supports only 1 visual at a time–VNC server must satisfy least capable client–Legacy X clients need 8-bit PseudoColor
Issues and Interactions between VNC and X
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•We run a mix of 8-bit and 24-bit VNC desktops•Distinguish by using distinct desktop BG color•Use 8-bit VNC desktops wherever possible
•Use 24-bit VNC desktops when required–Some GUIs require 24-bit visuals–Mix of GUIs exhausts 8-bit color map
Working within VNC's constraints:8- or 24-bit desktops?
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•Sites typically have a 3-screen and 1-screen W/S–3-screen W/S typically runs instrument s/w–1-screen W/S typically runs telescope s/w
•Run virtual window manager on local desktop–Have >= 4 window panes on each local screen–Run 8-bit VNC viewer in one window pane–Run 24-bit VNC viewer in another pane–Other panes allow access to local desktop
Example configurations
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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•Xinerama–Allows multiple screens to be treated as one–Windows can span screens or move between–Does not work well in conjunction with VNC
•Graphon's GO-Global product (proprietary)–Provides very efficient remote access–All state saved on server side (like VNC)–Does not provide desktop sharing
Other options explored
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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•x11vnc–Allows access to a non-virtual X11 desktop–Remote access w/out running within VNC–Relies on physical polling of frame buffer–Useful for remote troubleshooting–Current version is prototype / pre-release–Not yet sufficiently robust for remote observing
Other options explored
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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• Remote eavesdropping: (approximately 90%)–At least one member of observing team in Waimea–Other members of the team work from the mainland–Observers in Waimea have primary responsibility for operations–Observers on the mainland can 'eavesdrop' via VNC–Observers on the mainland can also operate instrument
• Mainland-only: (approximately 10%)–All members of observing team observe from mainland site(s)–Observers on the mainland have sole responsibility for operations
Two Modes of Remote Observing from the Mainland
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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• Overall usage has increased with growing number of sites• First three months of 2006: average 8 nights per month• May 2006: 12 nights of remote observing from mainland• Significant number of nights involve multiple mainland sites:
– Multi-site teams– Split nights: (e.g., UCSC first half on night, UCLA second half)– Both telescopes:
• UCB/LBNL remote observer using LRIS on Keck I Telescope• UCLA remote observer using OSIRIS/LGS-AO on Keck 2 Telescope
Current Usage Statistics for Keck mainland remote observing
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• Waimea has two remote ops rooms, one for each telescope• Each mainland site has only a single remote ops room• Potential conflict if both observing teams from same site:
–20 out of 181 nights (or 11%) in 2006A semester–Of those: 55% Caltech, 30% UCB, 10% UCLA, 5% UCSC–To date, no such conflicts have arisen
• Only enough ISDN lines at summit to backup one site–Not a problem for split nights–A potential problem for mainland-only from two sites on same night
Scheduling Issues and current constraints
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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• Upgrade ISDN capacity at summit to support multiple sites (install more lines & upgrade router, Summer 2006)
• Installation of dedicated VNC server hosts at Keck summit• Continue to optimize VNC configurations and performance• Implement RO facilities at other Keck partner institutions• Develop scheme for dynamic allocation of VNC server #s• Develop improved procedures for coordination between sites
Future plans
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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•Mainland remote observing (MRO) is operational– For all Keck optical instruments and most IR insts.
– From 5 mainland sites: (UCSC ,UCSD , Caltech, UCB/LBNL,UCLA)
– Shared VNC desktops used for most remote ops.
– Provides competitive performance for most GUIs
– Provides acceptable performance for image displays
•MRO efficiency would be enhanced by:– A distributed image display server / client (VO?)
– VNC server w/ simultaneous 8- & 24-bit support
Conclusion
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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•U.S. National Science Foundation
•University of Hawaii
•Gemini Telescope Consortium
•University Corp. for Advanced Internet Development (UCAID)
•Corporation for Education Network Initiatives in California (CENIC)
Acknowledgments
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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END OF PRESENTATION !!!
SPARE SLIDES FOLLOW
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Limitations of Remote Observing from Keck HQ in Waimea
Most Keck observers live on the mainland.
Mainland observers fly > 3,200 km to get to Waimea
Collective direct travel costs exceed $400,000 U.S. / year
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Keck Telescopes use Classical Scheduling
•Kecks not designed for queue scheduling
•Schedules cover a semester (6 months)
•Approved proposals get 1 or more runs
–Each run is between 0.5 to 5 nights long
–Gaps between runs vary from days to months
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Factors contributing to sluggish performance at mainland sites
Lower inherent bandwidth• High round trip time (RTT) between Keck and California
– Yields lower effective bandwidth for un-tuned TCP
– Slows any functions requiring multiple round trips
– High RTT limits benefit of tuning or compression• Routing and propagation delays change over time
– Keck/California link: hops / RTT• 1998: 12 hops / 70 millisecond average RTT• 2004: 22 hops / 100 millisecond average RTT• 2006: 17 hops / 90 millisecond average RTT
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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•Colormap issues
– slower scrolling if pixel retransmit needed
– colormap flashing if insufficient colors
– private color maps (Not supported in v4)
•Whitepixel and blackpixel conflicts
•Fonts are supplied by the X server
– Using X model, X server is local to observer
– Using VNC model, X server is at summit
Issues and Interactions between VNC and X
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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An alternative topology for using VNC with ssh and X
The VNC server and VNC viewer are both run on the same computer at the summit. The X display generated by the VNC viewer is re-directed to the remote site via a standard ssh tunnel.
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Benefits of this topology
• Retains most benefits of the first VNC topology:–Single-user applications can be shared between sites–Observing X clients connect to a local X server (short RTTs)–Speeds up functions that require multiple X transactions
• VNC not needed at remote sites; only at the summit
• Avoids ssh port-forward complexity
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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• Neither protocol is optimal for all applications & sites
• Some functions work better under X– image display functions (pan, zoom in / out, color map scroll)– iconifying / de-iconifying windows (if backing store enabled)– any functions more sensitive to bandwidth than to RTT
• Some functions work better under VNC– creation of new windows, pop-ups, and sub-panels– instantiation of pull-down menus– any applications that are RTT sensitive (Keck guider eavesdrop)
• Most output-only applications work OK using either
Using a mix of both protocols
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Multiple monitors facilitates a mix of X and VNC protocols
For example, one monitor can display a shared VNC desktop while the others carry the redirected X displays of X clients running at the summit.
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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•Local ds9ds9 X client and server: 6.6 seconds
•Summit ds9 display redirected to mainland
– direct to mainland X server: 72.0 (76.0*)
– via mainland VNC viewer: 11.0 (27.5*)
– via VNC viewer at summit: 10.6 (26.2*)
–* values in ( ) are without ssh compression
•In-stream compression helps in all cases
Measurements of remote performance: ds9 startup
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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•Local ds9ds9 X client and server: 3.0 seconds
•Summit ds9 display redirected to mainland
– direct to mainland X server: 10.3 (11.9*)
– via mainland VNC viewer: 3.0 ( 7.7*)
– via VNC viewer at summit: 3.0 ( 6.8*)
–* values in ( ) are without ssh compression
•In-stream compression helps in all cases
Measurements of remote performance: file chooser popup
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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•Local ds9ds9 X client and server: 0.7 seconds
•Summit ds9 display redirected to mainland
– direct to mainland X server: 4.0 (10.2*)
– via mainland VNC viewer: 9.0 (17.0*)
– via VNC viewer at summit: 6.5 (11.5*)
–* values in ( ) are without ssh compression
•In-stream compression helps in all cases
Measurements of remote performance: ds9 zoom in
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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•Local ds9ds9 X client and server: 0.0 seconds
•Summit ds9 display redirected to mainland
– direct to mainland X server: 0.1 ( 3.0*)
– via mainland VNC viewer: 4.0 (10.0*)
– via VNC viewer at summit: 4.5 (13.5*)
–* values in ( ) are without ssh compression
•In-stream compression helps in all cases
Measurements of remote performance: ds9 draw cut for plot
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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•Can redirect displays of legacy X clients:
– using X protocol
– using VNC protocol
– using a combination of both protocols
•Choice depends on functionality of each X client
•Good remote performance for most X GUI clients
•Need better remote performance for ds9
Summary
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Future directions
•Explore distributed ds9-like image displays:
– “ds9server”: an image / image section server• Runs on the instrument control computer on summit
• Interfaces to multi-HDU FITS images on disk or in shmem
• Extracts subset of pixels requested by display client(s)
• Efficiently transmits pixels and WCS-info to display client(s)
– “ds9viewer”: an image / image section client• Runs at remote site and provides local GUI to observer
• Convert GUI events into requests to transmit to ds9server
• Receives pixel / WCS-info stream transmitted by ds9server
• Displays pixel stream locally as a bitmap image or plot
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Future directions
•Explore distributed ds9-like image displays:
– design image server / viewer protocol to:• Minimize round trips between client(s) and server
• Support progressive/lossy transmission of image sections
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Keck 2 Remote Observing Room as seen from the Keck 2 summit
Telescope operators at the summit converse with astronomer at Keck HQ in Waimea via the videoconferencing system.
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Videoconferencing has proved vital for remote observing from Waimea
•Visual cues (body language) important!
•Improved audio quality extremely valuable
•A picture is often worth a thousand words
•Troubleshooting: live oscilloscope images
•“Cheap” desktop sharing (LCD screens)
•Chose dedicated versus PC-based units:
–Original (1996) system was PictureTel 2000
–Upgrading to Polycom Viewstations
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Interaction between video-conferencing and type of monitors
•Compression techniques motion sensitive
•“Moving” scene requires more bandwidth
•CRT monitors cause “flicker” in VC image– Beating of frequencies: camera .vs. CRT
– CRT phosphor intensity peaking, persistence
•CRT monitor “flicker” causes problems:– Wastes bandwidth and degrades resolution
– Visually annoying / nausea inducing
•Use LCD monitors to avoid this problem
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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The Keck Headquarters in Waimea
Most Keck technical staff live and work in Waimea. Allows direct contact between observers and staff. Visiting Scientist’s Quarters (VSQ) located in same complex.
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Motivations for Remote Observing from the U.S. Mainland
•Travel time and costs greatly reduced
•Travel restrictions accommodated–Sinus infections and ruptured ear drums
–Late stages of pregnancy
•Increased options for:–Student participation in observing runs
–Large observing teams with small budgets
•Capability for remote engineering support
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Santa Cruz Remote Observing Video Conferencing
Remote observer’s colleague in Waimea as seen from Santa Cruz remote ops
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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The Weather in Waimea
Remote observer in California points remotely-controlled camera at the window in Waimea remote ops
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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The Remote Observing Facility at Keck Headquarters in Waimea
•Elevation of Waimea is 800 meters
•Adequate oxygen for alertness
•Waimea is 32 km NW of Mauna Kea
•45 Mbps fiber optic link connects 2 sites
•A remote control room for each telescope
•Videoconferencing for each telescope
•On-site dormitories for daytime sleeping
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Mainland remote observing goals and implementation strategy
•Goals:–Target mainland facility to short duration runs
–Avoid duplicating expensive Waimea resources
–Avoid overloading Waimea support staff
•Strategy:–No mainland dormitories; observers sleep at home
–Access existing Waimea support staff remotely
–Restrict mainland facility to experienced observers
–Restrict to mature, fully-debugged instruments
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Mainland remote observing facility is an extension of Keck HQ facility
•Only modest hardware investment needed:–Workstations for mainland remote observers
–Network-based videoconferencing system
–Routers and firewalls
–Backup power (UPS) – especially in California!!!
–Backup network path to Mauna Kea and Waimea
•Avoids expensive duplication of resources
•Share existing resources wherever possible–Internet-2 link to the mainland
–Keck support staff and operational software
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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The initial model for Keck Remote Observing
•The control computers at the summit:–Each telescope and instrument has its own computer
–All operational software runs only on these computers
–All observing data written to directly-attached disks
–Users access data disks remotely via NFS or ssh/scp
•The display workstations–Telescopes and instruments controlled via X GUIs
–All users access these X GUIs via remote X displays
–X Client software runs on summit control computers
–Displays to X server on remote display workstation
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Operational simplifications
• Only one copy of operational software to maintain• Only “vanilla” hardware / software needed at remote site• Simplifies sparing and swapping of equipment• Simplifies system maintenance at remote site• Simplifies authentication / access control
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Focus effort on X standardization and optimization over long links
•Maintain consistent X environment between sites
•Optimize X performance between sites
•Eliminates need to maintain:
•Diverse instrument software at multiple sites
•Diverse telescope software at multiple sites
•Coordinate users accounts at multiple sites
•Fewer protocols for firewalls to manage
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Remote observing differences: Waimea versus the mainland
•System Management:
–Keck summit and HQ share a common domain
–Mainland sites are autonomous
•Remote File Access:
–Observers at Keck HQ access summit data via NFS
–Observers on mainland access data via ssh/scp
•Propagation Delays:
–Summit to Waimea round trip time is about 1 ms.
–Summit to mainland round trip time is about 100 ms.
Advanced Software and Control for AstronomyAstronomical Telescopes and Instrumentation / SPIE 2006 5/26/2006
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Shared access and control of instruments
•Most software for Keck optical instruments provides native multi-user/multi-site control
•All users have consistent view of status and data
•Instrument control can be shared between sites
•Multipoint video conferencing key to coordination
•Some single-user applications can be shared via X-based application sharing environments: