Zoom Orientation

Created Feb. 7, 2024 by Thomas McClain

Making sense of videoconferencing terms

ISDN - "integrated services digital network" - specialized phone lines traditionally used for videoconferencing.  Two types of ISDN includes basic rate interface or primary rate interface

Bridge - a device that connects multiple protocols traditionally ISDN (H.320) and TCP/IP (H.323). 

MCU - "multi-point control unit" - a device that connects multiple H.323 endpoints

SIP - "session initiation protocol" - a protocol originating from the phone industry for carry multimedia.   The protocol for the backbone of "Internet Telephony."    SIP is commonly used for desktop to desktop applications such as: Microsoft Lync and Zoom .

H.239 - a protocol that allow videoconference systems to send "content" in a parallel channel with the video.   The "content channel" is best suited for desktop sharing however, video streamed across the H.239 produces a less than desirable effect.




How does Zoom fit in

Zoom provides the following services:

  • web-based desktop videoconferencing
  • instant message server (chat)
  • multi-point control unit
  • bridge:  (audio and SIP)


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