VRVS Frequently Asked Questions


Basics

  1. What is VRVS?
  2. What is a Virtual Room?
  3. How to get started?
  4. Which platforms does VRVS support?
  5. How can I report bugs, comments, and other feedback?
  6. What kind of software do I need to make a videoconference?

Reflectors

  1. What is a reflector?
  2. How could I collaborate with your project and extend your reflectors' network to my area?

Configuration

  1. How to configure my sound device under Linux?
  2. What is internal loopback (local loopback)?
  3. How to connect two headsets in parallel?
  4. How to configure my firewall to use VRVS ?
  5. VRVS with Sun Java Virtual Machine

MBone

  1. Why doesn't RAT recognize my sound card?
  2. How to join Access Grid with VRVS Mbone tools successfully?
  3. Does USB camera work with VRVS Mbone tools under Linux?
  4. Which sound card works with RAT?
  5. RAT troubleshooting.
  6. Why do the MBone tools not start up on MacOSX

H.323

  1. How to join VRVS with NetMeeting successfully?
  2. Why I can't hear anything while using Polycom Viavideo with VRVS?
  3. How to connect Polycom ViewStation with VRVS?
  4. Is there any H.323 client compatible with VRVS in Macintosh?
  5. Which parameters should I choose for H.323?
  6. How to join Access Grid with H.323 client successfully?

Sharing

  1. How to share the documentation?
  2. Why is sound cut very often when VNC updates screen under Windows98?
  3. Is it possible to just share one application, not the whole desktop?
  4. Is it safe to use application sharing?
  5. How to change the default X Windows manager under Linux?

Miscellaneous

  1. Does VRVS work through a Proxy?
  2. Does VRVS work under Mac?
  3. Can I use VRVS at home with ISP?
  4. How can I connect SONY EVI-D30/D31 camera in daisy chaining?

Basics

  1. What is VRVS?

    VRVS is a web oriented system for videoconferencing and collaborative work over IP networks. The Virtual Room Videoconferencing System (http://www.vrvs.org) provides a low cost, bandwidth-efficient, extensible means of videoconferencing and remote collaboration over networks within the High Energy and Nuclear Physics communities. Recently VRVS also extends the service to other various academic/research areas.

    Since it went into production service in early 1997, deployment of the web-based system has expanded to more than 11,000 identical registered users running the VRVS software on more than 37,000 machines in 106 countries. A set of 81 VRVS Reflectors interconnected using unicast tunnels and multicast manage the traffic flow at HENP labs and universities in the US, Europe, Asia, and South America. VRVS provides the versatile collaboration tools: MBone (e.g. VIC and RAT), H.323 (e.g. Polycom, NetMeeting, Gnomemeeting), SIP, QuickTime, Desktop/Application sharing and Chat on various platforms.

    Recent and ongoing developments include support for MPEG2/MPEG4 and HDTV videoconferencing, shared collaborative environments, QoS over networks, etc. The goal is to support a set of new and essential requirements for rapid data exchange, and a high level of interactivity in large-scale scientific collaborations.

  2. What is a Virtual Room?

    When two or more people have a meeting, they usually join in a room or office inside a building and talk together for a while. When the participants of the meeting are far away, they join and talk inside a virtual place that we call Virtual Room. They can be miles away from each other, but using their browsers they can all join the same virtual space (the same Virtual Room) and see and talk among them, like if they would be together in the same physical room.

    To join a Virtual Room somebody must have booked it previously, in the same way people make reservations of physical rooms to celebrate their meetings. Read VRVS Booking Guide for more information about how to book a Virtual Room.) For more information about how to join a reserved Virtual Room, please read VRVS Connection Guide.)

  3. How to get started?

    If you want to use VRVS, you must first complete two basic steps:

    A) Registration/Login.
    VRVS 3.0 is user-oriented system. You only need to register once and after that, use your login/password to join VRVS no matter what machine you are using. You don't need to create multiple registration for different machine anymore. For mor detail information, please refer to VRVS Registration Guide.

    For more information see the Quick Start Guide.

  4. Which platforms does VRVS support?

    VRVS works under all OS includes Windows, Linux, Mac,  Solaris and Irix.

  5. How can I report bugs, comments, and other feedback?

    This FAQ should give an answer to the most common questions or problems encountered while you use VRVS. If none of these questions satisfy your requirements, try to have a look at the VRVS Documentation first. If you don't find what you're looking for, or you want to report a bug, comment or some other kind of feedback, fill the feedback form.

    When reporting problems please detail:

    1. which hardware platform and operative system version you are using.
    2. which browser (Netscape, Internet Explorer).
    3. which version of Java plug-in.
    4. when/where does the problem appear (when you are where and you click what)

    The more information you provide, the quicker we'll be able to assist you.

  6. What kind of software do I need to make a videoconference?

    We provide our VRVS package including MBone tools, sharing applications and remote camera control tools. Since VRVS 3.3, the MBone will be automatically downloaded and updated when you enter the Virtual Room.

    You can also use any H.323 client, like Polycom, Netmeeting, or SIP client, like Messenger, and Quicktime, etc. For more information about using these H.323 clients though the VRVS interface, Please refer to VRVS Application Guide


Reflectors

  1. What is a reflector?

    A reflector is a host that interconnects each user to a Virtual Room, by a permanent IP tunnel.

    The reflectors and their links form a set of virtual sub-networks through which audio, video or data, flows. The use of the reflector technology allows the system to be highly extensible, and assures the quality needed for videoconferences transmission.

    Participants at any location join videoconferences (in one or several virtual rooms) by contacting their "closest" reflector. In order to make an efficient use of bandwidth, packets (video, audio and data stream) are just sent through the tunnel that links two reflectors, if there are participants in the same virtual room on both sides. In addition, the network reflector topology is chosen taking into account both geography and the bandwidth available on each network link, in order to optimize the network-connectivity paths.

    At the registration process, the end-user is automatically attached to his/her nearest reflector. When the user starts a connection with VRVS, the system sends a connection request to its reflector. If the reflector doesn't answer, the user is automatically connected his/her nearest backup reflector.

  2. How could I collaborate with your project and extend your reflectors' network to my area?

    Please send an email to contact@vrvs.org with your proposition. We will study your case, and if we agree to install a new reflector at your site, we will send you all the technical information.


Configuration

  1. How to configure my sound device under Linux?

    First check to make sure that your sound device is supported by Linux.

    - Press Alt+Ctrl+F1 to enter text-mode virtual console. Login as root.
    - Run /usr/sbin/sndconfig, follow the Sound Configuration Utility to configure your sound device. Most of current sound devices can be PnP by Linux now.
    - If everything goes well, exit from sndconfig, and press Alt+Ctrl+F7 to return the graphical user interface.
    - Make sure the sound device is not muted by checking XMixer.

    lsmod and lspci can be helpful to check what kind of sound card you have and does the Linux recognize it well.

  2. What is internal loop (local loopback)?

    Some full duplex sound cards have the features that support internal loop. That means even there is no audio application running, you can still hear the voice from mike. Internal loop is good for some aspects such as microphone boost. However, it can be disturbing in the real-time conversation. When you talk, you can hear yourself after a few seconds.
    It can be disabled in audio control. In Windows Volume Control by clicking the small speaker icon in desktop the right corner task tray , select Options->Properties, check "Adjust volume for Playback" and select "Mic Volume", now you are able to mute/un-mute the microphone in playback. Remember though it only prevent internally speaker from playing back your microphone input audio. If you are using external speaker, it will still cause echo even high pitch noise by positive feedback between speaker and microphone. For some models of laptop, if you disable the internal loop, you may face another problem that the microphone is too weak to pick satisfying audio volume. There are always some compromises depending on how you can tolerant to hear your own audio loopback. 

    mic loop

  3. How to connect two headsets in parallel?

    It can be useful to have two headsets connected in parallel to the same VRVS client under noisy environment. Echo can be avoided and more than one people can use VRVS at the same time in this way. Use 2 set of 3.5mm stereo jack x 2 Y cables to connect the headsets. M/F extension cables may also be needed for easy connection to PC sound card. For the best performance, you should use the two identical headsets.

  4. How to configure my firewall to use VRVS?

    If there is a firewall blocking incoming traffic between your machine (inside firewall) and your attached reflector and backup reflector (outside firewall), some ports need to be open.

    The common firewalls seen on personal computer include Windows Firewall, ZoneAlarm in Windows, iptables in Linux, Personal Firewall in Mac OS X. For Windows SP2 related problem, please refer to VRVS Windows SP2 guide.

    If you have a firewall setting that even blocks outgoing traffic, you can grand them during connection per case or please send us email support@vrvs.org about what ports are used in VRVS.

  5. VRVS with Sun Java Virtual Machine

    Since VRVS 3.2, VRVS only supports Sun latest Java Virtual Machine (JVM).  To install Sun JVM, please go to www.java.com. Depending on your OS, you may have the choice to install it automatically or manually. If you have problem during installation, please refer to Java Technology Help.

    Under Windows, make sure you have Administrative privilege to install Sun JVM. You can install JVM by using the automatically "Get it now" installation or manually online/offline installation from http://java.sun.com/j2se/index.jsp. The safest and the last method to try is offline installation. You need reboot to finish the installation.

    After successfully installed the Sun JVM, you will be able to access it from Control Panel->Java Plug-in. From there, you can set Sun JVM as the default Java Runtime for your web browser. You may need to close all your browser windows and restart the web browser to reflect the changes. You can confirm your web browser has Sun JVM plug-in successfully installed from Sun Java Console output when you access www.vrvs.org.

    Sometimes you have to uninstall all the previous installed Sun JVM, reboot several times to install the latest Sun JVM.


MBone

  1. Why doesn't RAT recognize my sound card?

    Check if you don't have Realtec High Definition audio card(Realtek HD). This sound card is not supported by RAT. For you, only solution is to use some USB headset or echo canceler. You can find one at our recommendation page.

    Under Windows, you may first try to upgrade your sound card drivers, and even make "Windows Update" for the specific OS. Some users report that "Windows Update" fixes the problem. Under Linux, please make sure there are no problem for your sound card setting. 

    If you are using PC hardware, you should check that the DMA channels are configured correctly. This is a common error on Linux, since the RedHat sndconfig program can report a working configuration, even if these are set up wrongly.

    Another problem can be that you may be listening to audio from another program, perhaps the other program did not release the audio device and so RAT cannot connect to it. The command /sbin/fuser /dev/dsp will tell you if a program has the audio open (blank is good, means nothig has /dev/dsp open). Make sure you do not run "artsd" as this will not work with RAT. For more information go to: http://www.arts-project.org/doc/handbook/artsd.html.

    Note also that being able to play CDs or MP3 files on the machine is NOT an indication that your sound card is configured correctly for rat. Playing out audio is a half-duplex operation, rat requires that your card runs in full duplex mode." -- from RAT FAQ.

    But the GOOD NEWS is we have made progress in this area. Not all the sound cards are supported by the OSS sound interface. Please, install the ALSA sound interface, but with OSS emulation, now that RAT has implemented an OSS sound interface function. Please refer to the ALSA and OSS Simulation Installation Manual

  2. How to join Access Grid with VRVS MBone tools successfully?

    Through VAG - VRVS/AG Gateway, now you can enter an AG Virtual Venue and join AG meeting by using the MBone tools or H.323 client. By default you will receive all the video and audio streams by using MBone. You can select how you want to receive video by clicking "Video Modes" tab. You can set the display mode to "Voice Switched", "Timer Switched", "Selected Streams" or "All Streams ". For how the different video mode works, please refer to this documentation.

    It is the same way to join the AG meeting as to join a normal VRVS virtual room. You need first register yourself within VRVS, and go to the specific AG Virtual Venue through VRVS.

    Because of the different audio codec selected, there are some changes need to done. You need use RAT 5. For the most compatibility with different videoconferencing clients (MBone, H.323, QuickTime, JMF, etc), VRVS audio is following I.T.U H.323 mandatory implementation standard - G.711 PCM �-law compressed audio codec. AG uses uncompressed Linear L16-16-Mono codec. Only when you connect to AG with MBone tools through VRVS, you need set the audio codec to L16-16-Mono. To do it, you need change the RAT 5 audio setting as following:
    Click "Options" in RAT 5 and

    • select "Audio" category, change "Sample Rate" from 8-KHz to 16-KHz.
    • select "Transmission" category, and select "Linear-16".
  3. Apply the changes. If all the changes are done successfully, you should notice that the transmitting audio Bitrate changes from 64kbps to 256kbps. The default VRVS setting will be restored automatically next time when you join VRVS. For help on how to use RAT 5, please refer to VRVS RAT 5 Documentation.

  4. Does USB camera work with VRVS Mbone tools under Linux?

    Yes. Under Redhat 8.0 and 7.3, please refer to  http://www.isthe.com/chongo/tech/comp/pwc/ . The description below is based on what we have tested with Philips USB camera PCVC690K and Logitech QuickCam Pro 3000 on Redhat 7.2. First of all, you need to compile your Linux kernel (get a new kernel at  http://www.kernel.org/ ). Please refer to  http://www.smcc.demon.nl/webcam/  on how to compile it and install USB camera in Linux. VRVS installation package has already includes USB camera support. 

  5. Which sound card works with RAT?

    The following sound card status are reported by our VRVS users or tested by us. There are certainly more sound card models working with or NOT working with RAT . Welcome to report your experience on this issue.

    Sound cards that work with RAT 4 and RAT5 under Linux:

    • Ensoniq ES1371.
      • OSS: SigmaTel STAC9721/23. It works out of the box in Mandrake 8.1 with updated official kernel 2.4.8-34.ldmk.
      • OSS: Cirrus Logic CS4297A rev B.
    • Creative Labs SB Live! EMU 10000
      • OSS: Creative SBLive
    • Ess Maestro build in audio device.
    • Intel 82xxx AC'97 Audio (very last version of RAT).

    Sound cards work with RAT 4 and RAT5 under Windows:

    • Creative Sound Blaster AudioPCI 64V.
    • Ess Maestro build in audio device.
    • Intel 82xxx AC'97 Audio.

    Sound cards that are not supported:

    • Realtek HD
    • Yamaha YMF724.

  6. RAT troubleshooting.

    In any case you can download and install a different version of RAT from here.
    I can't receive/send audio with RAT

    Click RAT Options->Audio, does RAT recognize your sound card?

    If not, please refer to this FAQ.

    If yes, please make sure there is no other running applications using the device. If you are behind firewall, please refer to this FAQ.

    I can't receive audio until I start to speak If you are behind NAT/Firewall, some configurations need to active port for inside before receiving data from outside. Consult your local network admin.
    I can't listen and speak at the same time, one mute another.

    Click RAT Options->Audio, check Silence Suppression is set to Off. And no Additional Audio Options are checked.

    For more detailed troubleshooting, please refer to the decision chart on Linux or Windows .

  7. Why do the MBone tools not start up on MacOSX?

    It usually happens when you don't have X11 installed. If you are using Mac OS X 10.3.9 download and install X11 package X11User.pkg form apple site: http://www.apple.com/support/downloads/x11formacosx.html. If you are using Mac OS X 10.4.0 or later you can install X11 from your installation DVD. Run Optional Installs and in Application section select X11 and click on install.


H.323

  1. How to join VRVS with NetMeeting successfully?

    Windows NetMeeting 2.11 and 3.01 can be used as a H.323 client to join VRVS.  It has been reported that NetMeeting 3.0 in Windows 2000 seems trying to commute more ports other than video and audio for sharing and other NetMeeting features, which may hang the web browser. If your NetMeeting is behind firewall, you may want to refer to  Windows NetMeeting Firewall Configuration whitepaper .

    To be able to receive remote video, you must first be able to transmit video. Otherwise NetMeeting thinks itself doesn't have video capability even just to receive video during connection establishment. You can check from Menu "Tools"->"Video"->"Send".

    Please refer to Microsoft Support  How to Remove and then Reinstall NetMeeting (Q267958)  and  NetMeeting Homepage  for more information.

  2. Why I can't hear anything while using Polycom ViaVideo with VRVS?

    The most common error is wrong audio line connection between Polycom ViaVideo and PC. Check the audio line between Polycom ViaVideo audio output (which shows an icon as headphone) and your PC audio input is connected correctly. Line In should always be the first choice. If you don't have a Line In jack, select Mike Input. Please refer to ViaVideo Documentation for more information.

  3. How to connect Polycom ViewStation with VRVS?

    To use Polycom ViewStation with VRVS, you need go to http://www.vrvs.org. Enter the booked room and select H.323 tab. Type the hostname or IP address of your Polycom ViewStation (NOT the hostname/IP address of the PC). If you are using a gatekeeper, type the name there and your alias. The advantages here with VRVS are you can easily select different bandwidth (up to 768 Kbps), frame rate (up to 25/30 fps) and four view modes (Voice Switched, Timer Switched, Selected Streams and All Streams) through webpage. Please refer to VRVS H.323 Guide.

  4. Is there any H.323 client compatible with VRVS in Macintosh?

    Yes. SmithMicro Software has developed a H.323 client product under Mac - VideoLink Pro. More details can be found at their website  http://www.smithmicro.com/MAC_index.tpl .This software only works with Mac OS 8.6 through 9.x.

  5. Which parameters should I choose for H.323?

    VRVS provides the flexible H.323 parameters such as bandwidth and frame rate selection. You can select the appropriate ones based on the real network connection and certain scenario. Considering all the participants are using Polycom H.323 product, ViewStation and ViaVideo. Click "SET" button under H.323 at VRVS virtual room. For ViewStation, set hostname/IP as ViewStation's, bandwidth as 768kpbs, and frame rate as 25-30 fps. For ViaVideo, set hostname/IP as the attached PC's, bandwidth as 384kpbs, and frame rate as 25-30 fps. If the H.323 host is connected to a gatekeeper, you need to specify the gatekeeper hostname/IP and Alias or E.164 in the appropriate fields.

    If some of the participants are using MBone application, it will be safer to use 12-15 fps and adjust bandwidth based on packets loss. Please refer VRVS H.323 Guide.

  6. How to join Access Grid with H.323 client successfully?

    For the most compatibility with different videoconferencing clients (MBone, H.323, QuickTime, JMF, etc), VRVS audio is following I.T.U H.323 mandatory implementation standard - G.711 PCM �-law compress audio codec. Access Grid uses uncompressed Linear L16-16-Mono codec. VRVS has implemented the audio transcoder to transparently convert AG L16-16-Mono audio to PCM �-Law audio stream. In this way H.323 can join the AG session directly without changing anything. By default, your H.323 will display the first coming in video randomly. You can select how you want to receive video by clicking "Video Modes" tab. You can set the display mode to "Voice Switched", "Timer Switched", "Selected Streams" or "All Streams ". For how the different video mode works, please refer to this documentation.

    All the participated Access Grid nodes need to check they are using L16-16-Mono codec with packet duration 10ms. It can be confirmed by checking "Transmission" category. Under "Audio Encoding", unit should be set to 1. You can select from unit 1/2/4/8/16/32/64, VAG can handle all with some more programming. But it is not recommended. The reasons are:

    • L16-16-Mono is uncompressed audio codec, it is not the best choice for wide internet usage. Bigger packet unit will cause more noticeable audio packet loss and audio cut.
    • L16-16-Mono default packet duration is set to 10ms, corresponding unit 1 in "Transmission" category.
    • We need to follow at least a little bit of coherence in the standard used.

Sharing

  1. How to share the documentation?

    You have many ways to share the documentation in VRVS.

    • During Virtual Room reservation, you can attach URL links of the documentation. During the meeting, there will be a list of file icons showing at the bottom, participants can click to see the documentation;
    • VRVS chat room has the functionality to do "Synchronized Web Browsing". Type in the URLin Chat, the specified URL page will appear in all the participants of the chat room;
    • Similarly select Sharing tab, and put URL in Broadcast URL entry;
    • In normal virtual meeting, one of the participants can sharing his/her desktop or single application in different sharing level (interact/view only) and color mode (256 colors/true color). It is also can be used to sharing presentation.

  2. Why is sound cut very often when VNC updates screen under Windows98?

    Because Windows98 is not a real multitask/multithread OS, during different applications/windows switching, the audio program will stop for a while. Especially resource critical application, such as VNC, upgrades screen. Under Linux OS, this problem is much better. It also depends on the CPU/Memory loads.

  3. Is it possible to just share one application, not the whole desktop?

    Yes. Currently there is an add-on for single application sharing VNC server under Windows. Please refer to http://ultravnc.sourceforge.net/.

  4. Is it safe to use application sharing?

    As an opensource freeware, VNC provides the basic authentication with a challenge-response system. It's pretty safe if you use the "Broadcast Only" sharing mode in VRVS. The passward to login the VNC server is kept completely secret from all the participants of the virtual room. The participants can only start our java Applet client to view shared application. VRVS Gateway tracks the information and will stop and clean up session after user stops application sharing. This is reasonably secure; the password is not send over the network. With more security concern about afterward transmission, you can tunnel the VNC protocol through some more secure channel such as SSH. Another advantage of tunneling through SSH is compression gain.

  5. How to change the default X Windows manager under Linux?

    By default, vncserver use twm X Windows manager. To change it to other X Windows manager, you can modify under your home directory .vnc/xstartup. For example, to use gnome, you can comment out twm & line and add exec gnome-session &.


Miscellaneous

  1. Does VRVS work through a Proxy?

    Yes. VRVS needs to know the hostname of your machine, in order to send the video, audio and data stream directly to the right machine (not to the web proxy). If you are behind a web proxy, VRVS will go though it and will get your real IP address or hostname. This information will be stored in our database and you won't have any problems following your videoconferences.
    Please, remember that you must have "Java", "JavaScript" and "Accept ALL Cookies" options enabled in your web browser.

  2. Does VRVS work under Mac?

    Yes. VRVS support Mac OS X. For Mac OS 9 or less, you can use QuickTime to receiving VRVS streaming.  You just can receive one video and one audio at a time.

    Our new reflectors manage the voice switching, so you can always see and hear the video and audio of the participant who is speaking. Please refer VRVS QuickTime Guide  for more detail.

  3. Can I use VRVS at home with ISP?

    Yes, as long as the bandwidth is big enough for audio/video transmission. Basically 384 kpbs is enough for audio/video transmission, but it also depends on how many participants in the meeting and bandwidth your ISP provides. Cable modem or ASDL connection is good enough for using VRVS at home.

  4. How can I connect SONY EVI-D30/D31 camera in daisy chaining?

    EVI-D30/31 can be controlled by RS-232C serial control using VISCA. VISCA is an acronym of Video System Control Architecture. It is a network protocol designed to interface a wide variety of video equipment to computer. Under VISCA, up to 7 EVI-D30/31 can be connected to one controller using RS-232C communication. RS-232C parameters are communications speed of 9600 baud, data length of 8 bits, 1 stop bit and no parity. VISCA is a trademark of SONY Corporation. You should be able to find more details on EVI-D30/D31 daisy chaining in the product manual.




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