Internet 2 Commons Technology H 323 Overview Dr

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Internet 2 Commons Technology: H. 323 Overview Dr Bob Dixon Chief Research Engineer OARNet

Internet 2 Commons Technology: H. 323 Overview Dr Bob Dixon Chief Research Engineer OARNet and Ohio State University Internet 2 Commons Site Coordinator Training September 27, 2004 Austin, Texas

Video Conferencing vs. Video Broadcasting Video Conferencing Video Broadcasting Like a telephone call Like

Video Conferencing vs. Video Broadcasting Video Conferencing Video Broadcasting Like a telephone call Like watching Television Two - Way One - Way Call up or Answer Tune In or enter URL Streaming Webcasting 2

Internet Unicast Video Broadcasting Minnesota Colorado New York Internet Ohio 3

Internet Unicast Video Broadcasting Minnesota Colorado New York Internet Ohio 3

Internet Multicast Video Broadcasting Minnesota New York Colorado Internet Ohio 4

Internet Multicast Video Broadcasting Minnesota New York Colorado Internet Ohio 4

Internet Point-to-Point Videoconferencing Minnesota New York Internet Colorado Ohio 5

Internet Point-to-Point Videoconferencing Minnesota New York Internet Colorado Ohio 5

Internet Multipoint Videoconferencing Minnesota New York Internet Colorado MCU Ohio 6

Internet Multipoint Videoconferencing Minnesota New York Internet Colorado MCU Ohio 6

Two Types of Video Conferencing Traditional Internet Use in special room; rare Use anywhere;

Two Types of Video Conferencing Traditional Internet Use in special room; rare Use anywhere; ubiquitous Uses ISDN telephone lines Uses Internet High installation cost Low installation cost High usage cost No usage cost Usage at plateau Usage growing rapidly Scheduled in advance Impromptu Professional operator Do-it-yourself Centralized control Decentralized control H. 320 standard H. 323 standard 7

Requirements Good Quality DESKTOP Internet Videoconferencing 1. Fast PC. 500 MHz minimum. 2 GHz

Requirements Good Quality DESKTOP Internet Videoconferencing 1. Fast PC. 500 MHz minimum. 2 GHz best. 2. Good quality video conferencing equipment. Forget “web cameras”. Forget software like Netmeeting. 3. GOOD Internet connection. Most large university networks are good. Forget 56 K modem dial-in. Cable modems and DSL are possible. 8

Video Conferencing Products 1. Software-based Generally slow and non-standard; not very satisfactory. Examples: Microsoft

Video Conferencing Products 1. Software-based Generally slow and non-standard; not very satisfactory. Examples: Microsoft Net. Meeting, White Pine CUSee. Me. But new products from Polycom, RADVision, Vcon are promising. 2. Hardware-based, plug into PC USB Port. Newest approach; will become ubiquitous Examples: Polycom Via. Video, VCON Vi. Go. 3. Hardware-based, standalone appliance, no PC involved. Easiest to use, best quality. Example: Polycom Viewstation VSX-7000 9

Typical Equipment Desktop and Laptop: Polycom Via. Video - cost $400 Also requires PC

Typical Equipment Desktop and Laptop: Polycom Via. Video - cost $400 Also requires PC Classroom and conference room: Polycom Viewstation - model VSX-7000 - Cost $5000 Also requires TV monitor or projector 10

H. 323 Video Components Appliance Gatekeeper Remote H. 320 Video Rooms Multipoint Control Unit

H. 323 Video Components Appliance Gatekeeper Remote H. 320 Video Rooms Multipoint Control Unit ISDN Telephone Lines Gateway Internet PC Client 11

Multipoint Control Unit (MCU) 1. Allows more than two people to be in a

Multipoint Control Unit (MCU) 1. Allows more than two people to be in a video conference. 2. May be physically located anywhere on Earth. 3. Functions as an Internet server for video conferencing. 4. Every person’s audio is always heard by all others. 5. Video from the person who talks loudest is seen by all. 6. Various brands have various capacities and features. 7. Multiple MCUs may be cascaded together for larger video conferences. Or used separately for more simultaneous video conferences. 12

Gateway (GW) 1. Joins H. 320 ISDN video calls with H. 323 Internet video

Gateway (GW) 1. Joins H. 320 ISDN video calls with H. 323 Internet video calls. 2. Calls may be initiated from either side. 3. May be physically located anywhere on Earth. 4. Various brands have various capacities and features. 5. Multiple gateways may be used for more simultaneous calls. 13

Gatekeeper (GK) 1. Controls all MCUs, gateways, and clients in its “zone”. A zone

Gatekeeper (GK) 1. Controls all MCUs, gateways, and clients in its “zone”. A zone is any collection of H. 323 devices you choose to work closely together. The devices may be physically located anywhere on Earth. 2. All H. 323 devices must “register” with a gatekeeper, before they can do very much. 3. There can be only one active gatekeeper in a zone. 4. May be physically located anywhere on Earth. 5. May be physically located in an MCU, a gateway, a router, or a PC. But it is independent of them. 6. Multiple gatekeepers may be “neighbors” of each other, in different zones. 14

Gatekeeper (GK) (contined) 7. Provides calling with “telephone numbers” and nicknames, instead of IP

Gatekeeper (GK) (contined) 7. Provides calling with “telephone numbers” and nicknames, instead of IP addresses. A gatekeeper is analogous to a domain name server, in this sense. 8. Provides optional control of what each user can do: bandwidth and speed limits access to gateways and MCUs 9. Note that calls DO NOT go THROUGH a Gatekeeper. 15

H. 323 Videoconferencing H. 320 ISDN Gate. Keeper MCU Gateway Telephone POTS line H.

H. 323 Videoconferencing H. 320 ISDN Gate. Keeper MCU Gateway Telephone POTS line H. 323 Real Video INTERNET Web Browser H. 323 Clients 16

Useful References 1. Educause Quarterly tutorial article http: //www. educause. edu/pub/eq/eqm 004. html 2.

Useful References 1. Educause Quarterly tutorial article http: //www. educause. edu/pub/eq/eqm 004. html 2. The Video Conferencing Cookbook, and other materials at http: //vide. utk. edu 3. The Megaconference http: //www. megaconference. org 17