H.323 Version 2 Fast Connect | H.225 Message Element | CCIE Collaboration Exam

H.323 Version 2 Fast Connect

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Which element was added to H.225 messages to enable Fast Connect in H.323 version 2?



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A. B. C. D. E.


Fast start allows for H323 media connections to be started at the beginning of a call.

This is helpful for ringback scenarios, and also reduces the amount of time calls take to establish media.

H245 is still negotiated later, but the actual media can be done earlier through H225 messages.

The correct answer to this question is option A: fastStart.

H.323 is a protocol suite used for voice and video communication over IP networks. H.225 is a component of H.323 that deals with call signaling and call setup. H.225 messages contain various parameters and information elements that are exchanged between the endpoints during the call setup process.

Fast Connect is a feature introduced in H.323 version 2 that enables faster call setup by reducing the number of signaling messages exchanged between the endpoints. In traditional H.323 call setup, the endpoints exchange a series of messages to negotiate various parameters and capabilities before establishing the actual media stream. This process can take several seconds and result in delays and call setup failures in some cases.

Fast Connect addresses this issue by introducing a mechanism to streamline the call setup process. When a fast-connect-capable endpoint receives a call setup request, it can respond with a single H.225 message that contains all the necessary parameters and capabilities. This message is called a fastStart message and contains the following elements:

  • Source and destination addresses
  • Call type (audio, video, etc.)
  • Codec information
  • Network bandwidth requirements
  • Other call setup parameters

The receiving endpoint can then use this information to establish the media stream without further negotiation.

In summary, fastStart is the element added to H.225 messages to enable Fast Connect in H.323 version 2.