MBONE: Multicasting Tomorrow's Internet
You can find IP multicast extensions for UNIX via FTP at ftp.parcftp.xerox.com under /pub/net-research/ipmulti3.5-*.tar.Z. Other sites where you can find the multicast extensions include: louie.udel.edu:/pub/people/ajit/ipmulti3.5-*.tar.gz and ftp.adelaide.edu.au:/pub/av/multicast/ipmulti3.5-*.tar.gz.
The distribution includes kernel modifications for SunOS 4.1.3, SunOS 4.1.3_U1B, and SunOS 4.1.4, as well as the mroute daemon and various supporting binaries.
Once your workstation knows how to send and receive multicast packets, you'll need to get the software tools to make use of the MBONE. A wide variety of software is available -- the major packages for MBONE multimedia are covered next. The standard multimedia setup for conferencing on the MBONE includes whiteboard (wb), the visual audio tool (vat), and session directory (sd). Make sure that you pick up these three essential tools.
The following excerpt is from the nv main page:
nv allows users to transmit and receive slow frame rate video via UDP/IP across an internet. Video streams can be either sent point to point, or sent to several destinations simultaneously using IP multicast. Receivers need no special hardware - just an X display. Transmitters need some sort of frame capture hardware. Several different boards are supported so far, with more to come in future releases.You can get nv via FTP from ftp://parcftp.xerox.com/net-research/nv*
By default, the video transmitted is a 320x240 image for NTSC, or 384x288 for PAL. It can be sent either as 8-bit greyscale, or 24-bit YUV 4:2:2 color. Other sizes (both smaller and larger) can also be selected. It will be displayed at the receiver using a 24-bit color visual if one is available. If not, it will be dithered using whatever the default visual is. The frame rate varies with the amount of motion and the bandwidth available. Frame rates of 3-5 frames/second are typical for the default bandwidth of 128 Kbps. Some systems will support higher frame rates if the bandwidth is raised or smaller images are sent.
The following excerpt is from the wb README file:
If you simply want a shared "whiteboard" drawing surface, you don't need to do anything but install wb. But wb can also be used to export, view and annotate arbitrary PostScript files. If you want to include PostScript images in your wb conference, either your X server has to support Display PostScript (the DEC & SGI X servers do) or wb has to be able to exec the public domain postscript renderer 'GhostScript'. If you want to render postscript with Ghostscript, it has to be installed on your machine and has to be in your shell search path with the name "gs". (If you don't have Ghostscript it can be ftp'd from prep.ai.mit.edu, file pub/gnu/ghostscript-*.tar.Z.).Versions of wb are available for Linux, Sun, Silicon Graphics, DEC, and Hewlett-Packard systems, with ports in progress for Macintosh. You can find them via FTP at ftp://ftp.ee.lbl.gov/conferencing/wb.
vat enables private communications between two hosts (well, as private as anything zipping unencrypted over the Internet can be), as well as public audioconferencing. vat provides a variety of compression formats, allowing it to interoperate with several platforms and programs. vat will even let you chat with users on Windows or Macintosh PCs, assuming that they have audioconferencing software on their end, too.
vat provides conference hosts a list of all the other hosts that are currently tuned in to a multicast session -- a nifty way to tell how many others (and who) are listening to your lecture, diatribe, or ad-hoc Internet Radio show. Ready-to-run versions of vat are available for Sun, Silicon Graphics, DEC, Linux, and Hewlett-Packard platforms, with ports in progress for Macintosh. On most architectures, no special hardware other than a microphone is required -- sound I/O is provided via the built-in audio hardware.
You can get vat via FTP from ftp://ftp.ee.lbl.gov in the conferencing/vat* directory.
You can receive NeVot via FTP from ftp://gaia.cs.umass.edu/pub/hgschulz/nevot or ftp://ftp.fokus.gmd.de/pub/minos/nevot. Precompiled versions are available for SPARCstations, Hewlett-Packard 9000 running HP-UX, SGI running Irix 5.2, DEC Alpha running OSF 1.0, DECstation running Ultrix, IBM workstations running AIX, and Linux workstations.
ivs is available by anonymous FTP from zenon.inria.fr:rodeo/ivs/last_version. For more information about ivs, visit the ivs home page at http://www.inria.fr/rodeo/ivs.html.
Sd is available precompiled for Sun, SGI, Linux, DEC, and other operating systems. You can get it via FTP from ftp://ftp.ee.lbl.gov/conferencing/sd.
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