Protocol stack consideration » History » Version 5
AUGER, Anne sophie, 03/23/2015 07:48 PM
| 1 | 5 | AUGER, Anne sophie | h1. Network architecture |
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| 3 | 5 | AUGER, Anne sophie | * Frame format |
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| 5 | 5 | AUGER, Anne sophie | The application foreseen aims at transmitting video streams, so we choose to use the MPEG-4/H264 coding standard, and the adapted codec x264 for video compression/decompression. The associated frame format MP4 is used for the encapsulation of multimedia data type. As a result of this encapsulation, we will transmit longer frames, containing not only data bits, but encaplsulation bits (header, footer...). Therefore, we must consider a higher bit rate than the effective video bit rate. |
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| 7 | 5 | AUGER, Anne sophie | * Protocol stack |
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| 9 | 5 | AUGER, Anne sophie | We define here a first sketch for the protocol stack that would best fit this application: |
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| 11 | 5 | AUGER, Anne sophie | - Transport layer: the transmission content is video stream, and our application requires real time performance. Therefore the Real Time transport protocol (RTP) seems adapted for the project. In fact RTP adds a header to UDP packets, which specifies the transported media type and format (codec) and numbers the packets to handle losses. |
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| 13 | 5 | AUGER, Anne sophie | - Network layer: the real time constraint also imposes to minimize the packet transmission time. The solution for that is to use UDP transport |