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Projects : Secure Videoconferencing : Demo Instructions

Operating instructions for Secure Video Demonstration

    Server (Transmitter) instructions

     

    The machine is booted in single-user mode. (Key is in service position during boot and option 5 is selected from the menu for single user mode.) The password for the transmitting machine at the microscope is the normal root password.

     

    Run xinit to start an X environment.

     

    The programs are in directory /tmp/.i2demo :

    vvic The main video application (uses Virtual smartcard routines for key exchange)
    vat The sound application.
    resetether shell script to take down and reset ethernet interface
    runvic shell script to start vic without having to type all that info every time.

     

    Verify that the ethernet address, broadcast address, and gateway address in the resetether script are correct before running it!

     

    Verify that the destination address is correct in the runvic script before running it.

     

    Starting transmission:

    • cd to the /tmp/.i2demo directory
    • start a C-shell
    • source .env to pick up the SOM environment
    • Start vic (vvic) using the runvic script. The main window will appear and "waiting for video" should be displayed.
    • Select the MENU button to prepare for transmission.
    • Within the Transmission section, move both sliders all the way to the right (288000 Kbps, and 30 frames per second).
    • Within the Encoder section, select jpeg encoding. After selecting jpeg, move the Quality slider to the right for a quality factor of 77.
    • Select the Transmit button to begin transmission.

    Note: At this point several messages will appear in the window from which runvic was started. These messages are caused by the loopback code that is trying to display the video that it is sending. The video device is already opened for encoding and cannot be opened for decoding. You can ignore these messages.

     

    The "rate control" within the Transmission section of the MENU should show 30fps and somewhere around 4.5Mbps (this will vary depending on the content of the video). Note that after a period of time, the bps number may go to zero, but the fps will stay at 30. This is a bug where they count total bytes sent and the number wraps. As long as the frame rate stays up, itís still transmitting.

     

    Starting an encrypted session

    The "key exchange" can be initiated by either the sender or the receiver. This has to be coordinated out-of-bandÖ

    Initiating key exchange:

    • Select the "Initiate Secure Session" button. This will cause a dialog to appear on the receiverís screen asking whether they want to start a secure session. They should accept and then be prompted for an encryption method. The "Initiate Secure Session" button is updated as the key exchange procedure proceeds.
    • After the receiver selects an encryption type, a dialog should appear asking which encryption method you would like to use. Choose VRA initially.

    Note: At this point several messages will appear in the window from which runvic was started. These are debug messages showing the key exchange information.

    • The "Initiate Session Session" should now be disabled and should read "Session is Secured" and the encryption selection buttons should now be enabled so that any encryption method can be selected.

     

    Accepting key exchange:

    The receiver will have selected the button to initiate secure session.

    • A dialog will appear asking whether to start a secure session. Select YES.
    • Another dialog will appear to select the initial encryption method. Select VRA.
    • Once the initiator selects an encryption method, the "Initiate Secure Session" should be disabled and should read "Session is Secured" and the encryption selection buttons should now be enabled so that any encryption method can be selected.

     

    Receiver instructions

    The machine is booted in single-user mode. (Key is in service position during boot and option 5 is selected from the menu for single user mode.) The password for the transmitting machine at the microscope is the normal root password.

     

    Run xinit to start an X environment.

     

    The programs are in directory /tmp/.i2demo :

    vvic The main video application (uses Virtual smartcard routines for key exchange)
    vat The sound application.
    resetether shell script to take down and reset ethernet interface
    runvic shell script to start vic without having to type all that info every time.

     

    Verify that the ethernet address, broadcast address, and gateway address in the resetether script are correct before running it!

     

    Verify that the destination address is correct in the runvic script before running it.

     

    Starting reception:

    • cd to the /tmp/.i2demo directory
    • start a C-shell
    • source .env to pick up the SOM environment
    • Start vic (vvic) using the runvic script. The main window will appear and "waiting for video" should be displayed.
    • Wait for the transmitter to start sending. Thatís it!

     

    When receiving the data, there should be a grey thumbnail window with source and rate information. It should (eventually) show 30fps and somewhere around 4.5Mbps (this will vary depending on the content of the video). Note that after a period of time, the bps number may go to zero, but the fps will stay at 30. This is a bug where they count total bytes sent and the number wraps. As long as the frame rate stays up and the video is still coming, itís still receiving.

     

    Problems

    Problem: The transmitter says it is sending at 30fps at some bandwidth, but the receiver is losing a large percentage of the data and getting very poor video.

    Solution: Quit vic on both sides, run the resetether script to reset the ethernet interface and try again. If the problem persists, reboot the transmitter machine. Donít know why, but this has fixed it every timeÖ

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