Streaming Media Supplement sa2150 and sa2250

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Chapter 5 Understanding Media-IXT and QuickTime
3. Media-IXT rewrites URLs in the client request, replacing the advertised site name with the hostname of the
origin QuickTime server.
Our example URL would be rewritten:
rtsp://reallygreatmovies.com:554/epic.mov/
4. Media-IXT opens a TCP connection to the origin QuickTime server at the rewritten URL, dedicating the
connection to the client which sent the request.
5. Media-IXT determines whether the requested content is in cache, and whether it is fresh.
6. If the content is in cache but stale, or is not in cache, Media-IXT pulls the requested content from the origin
QuickTime player, and caches the content while streaming the content to the QuickTime player.
If the content is in cache and is fresh, Media-IXT streams the content to the QuickTime player, and does
not need to pull the content from the origin server.
Media-IXT streams content to the QuickTime Player client over UDP.
Figure 5-4. QuickTime reverse proxy caching example
Origin
QuickTime server
http://
reallygreatmovies.com/
Client brow ser with
QuickTime player
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The QuickTime player sends an RTSP request cont aining t he URL
rtsp://greatmovies.com:554/epic.mov/.
Media-IXT findsthe hostname of the origin QuickTime server in the map rules contained in
the
remap.config
configuration file.
Media-IXT rewrites URLs in the client request, replacing the advertised site name with the host-
name of the origin QuickTime server. Our example URL is rewritten:
p
rts ://re allygreatmovies.com:554/epic.mov/
Media-IXT opens a TCP connect ion t o t he origin QuickTime server at the rewrit ten URL
Media-IXT det ermines w het her t he request ed content is in cache, and w het her it is f resh.
The content is in cache and isfresh, so Media-IXT doesnot need to pull the content from
gthe ori in server.
Media-IXT streams content to the QuickTime player.
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map rule locat ing t he origin RealServer:
map rt sp://w w w.great movies.com/ rtsp://w w w.reallygreat movies.com/ QT
media content URL
rt sp://greatmovies.com:554/epic.mov/
+
map rule:
map rt sp://great movies.com/ rt sp://reallygreat movies.com/ QT
=
rewritten URL:
rt sp://reallygreat movies.com:554/epic.mov/
RTSP request for:
rtsp://greatmovies.com:554/epic.mov/
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http://www. greatmovies .com/
5
tcp
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4
Me ia-IXTd