Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 1 Packet Video & Audio Tools on PC’s (A Cookbook) February 7-11, 2000 H.A. “Kipp” Kippenhan, Jr.

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 2 Outline l Classification of systems l Packet Tools - Background l ITU Standards l Applications l Audio considerations l Video considerations l Additional suggestions l Summary l Questions

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 3 Classification of Systems – Pre H.323

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 4 Classification of Systems – Post H.323

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 5 Packet Tools - Background l Genus of the tools was research at Xerox PARC and Lawrence Berkeley Laboratory l Tools generally needed to participate »sdr (session directory) »vic (video conferencing tool) »rat (robust audio tool) »vat (visual audio tool) »wbd (white board) l Targeted for IP multicast (interactive use is more demanding) l What works well on Unix workstations may work differently (?not so well?) on PC’s

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 6 ITU Standards l H.320 umbrella standard Video & audio over public switched telephone network (e.g. - ISDN) l H.323 umbrella standard Video & audio over networks with no Quality of Service guarantee (i.e. – TCP/IP) l Video encoding »H.261 encoding (part of H.320) ­Discrete cosine transform encoding ­Maximum of 352x288 pixel resolution ­Subset of MPEG encoding (optimized for symmetric transmission/reception)

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 7 ITU Standards l Video encoding »H.263 encoding (part of H.323) ­Improved motion compensation (a factor of 5) ­Maximum of 352x288 pixel resolution ­Provision for 704x576 and 1408x1152 resolution (no products presently available) l Audio encoding (H.320 & H.323) »G.711 encoding – 3 KHz audio (uses 48, 56 or 64 Kbps of bandwidth) »G.722 encoding – 7 KHz audio (uses 48, 56, or 64 Kbps of bandwidth) »G.728 encoding – 3KHz audio (uses 16 Kbps of bandwidth)

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 8 ITU Standards l Audio encoding (H.323 unique) »G.723 – 3 KHz audio (uses 6.4 or 5.3 Kbps of bandwidth) »G.729 – 3 KHz audio (uses 8 Kbps of bandwidth) l What’s important »Only G.711 must be supported (even in H.323 products) »G.723 encoding is shipping in commercial products (e.g. – Cisco) »H.323 encoding only supports 352x288 pixels (in products shipping today) »Voice over IP products are classed as H.323 compliant

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 9 The Applications l Audio Tools Provide for the transmission/reception of audio information via packet networks l Vat (4.0b2) »Provides echo cancellation »PC version not full duplex audio »No recent development work l Rat (v ) »No echo cancellation »Supports full-duplex audio »Supported by UCL (MECCANO project)

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 10 The Applications l Video tools Provide for the transmission/reception of video information via packet networks l Nv »Doesn’t support H.261 encoding »Supports 640x480 resolution »No recent development l Vic (2.8ucl-1.0) »Support H.261 and H.263 encoding »352x288 (FCIF) resolution (640x480 – nv encoding) »Supported by UCL (MECCANO project)

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 11 The Applications l Other tools There are a variety of other tools (e.g. – HEPNRC multi-session bridge, VRVS) available for various special needs. They won’t be discussed here l Sdr (ver. 2.9) »Supports the announcement of or joining of IP multicast sessions on the Mbone »If announcing a session, the sdr process must not be stopped (announcement will disappear) »Automatically launches other tools (vic, rat, wbd, …) »Supported by UCL (MECCANO project)

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 12 The Applications l Wbd (ver. 1.0ucl4) »A conferencing tool – not a drawing tool »Import previously prepared drawings (postscript format) »Supports shared text (like ‘chat’) »Supported by UCL (MECCANO project)

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 13 Audio Considerations l Only important if you want to present (i.e. – source audio) l Echo cancellation »Not supported by rat »For groups, use hardware that supports it (e.g. – Polycom SoundPoint (speaker / microphone) l Audio level control Too many level controls to tweak (especially with Windows) »On speaker »Sound card (software – in systray) »Application (slider bar in rat)

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 14 Audio Considerations l Karaoke effect »Disable feature when using rat or vat »PC sound system usable as a Public Address (PA) system l Full-duplex problem »PC hardware ­Chipset on motherboard (not full-duplex until recently) ­Discrete sound card (may not be full-duplex) »Driver ­May not support full-duplex operation »Verification ­Must do a point-to-point connection using rat

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 15 Audio Considerations l Windows 2000 now shipping »Don’t assume anything »Compatibility issues »Users must perform tests

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 16 Video Considerations l Only important if you want to present (i.e. – source video) l Video capture card unnecessary if PC operating system supports USB devices - use a USB camera (e.g - 3Com #3718) l Drivers are always a problem (get latest from vendor web site) l HEPNRC has had success with the Hauppauge Win- TV (model 401) l Windows 2000 now shipping »Compatibility issues »Users must perform tests

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 17 Additional Suggestions l For a single user, get a headset (e.g. – LabTec C-324) l Disable ‘suppress silence’ option in audio tool (not doing so produces unacceptable audio performance on PC’s) l Adopt push-to-talk model (use mouse to enable microphone) l Accept variability of audio level between systems l Test your system before the day of an important meeting l Currently no bridge between H.323 / H.323 end points and packet tools (e.g. – Polycom to VRVS)

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 18 Summary l H.323 (connection based) devices are appearing at HEP research sites l There’s still life in your H.320 (ISDN based) codec l New codec purchases should support both standards – H.320 & H.323 (e.g. - Polycom Viewstation) l MCU’s (e.g. – Accord MGC-100) will support hybrid meetings (mixture of H.320 & H.323 devices) l IP firewalls and H.323 devices don’t interoperate well (it takes some tuning)

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 19 Summary l Vic (H.263) and rat (G.728) support necessary standards – why don’t H.323 systems interoperate with VRVS? »No way to do call-setup »Many H.323 systems don’t support rtp protocol l Suggestion – consult the following web page:

Network Resource Center H E P Fermilab Feb 7-11, 2000 CHEP 2000 Slide 20 Questions l ???