Streaming Media Supplement sa2150 and sa2250

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Chapter 3 Understanding Media-IXT and RealNetworks
in cache.config should prevent a PNA clip from being cached on the host, but does not.
(10.10.10.10
is an example IP address.) This is a bug, which can not be fixed, due to limitations of the
PNA protocol.
The proxyability part of the selective caching feature does work correctly for PNA (it is effected by
editing filter.config).
Authenticated PNA goes into passthrough.
Authenticated PNA requests may either be logged as
passthrough or may not be logged at all in the RealProxy's proxy.log file.
The content from these requests is not cached.
This is a design limitation associated with PNA.
Playback of high bandwidth content for PNA disrupted by seek.
High bandwidth content for PNA is very
rare, almost nonexistent.
Playback of high bandwidth content for PNA (using PNA with UDP as underlying transport protocol) can be
disrupted by even a single seek.
Symptoms include loss of audio, synchronization problems between audio and video, and video distortion.
PNA requests from downstream forward proxy caused upstream reverse proxy to crash.
Where one
Media-IXT cache was an explicit forward proxy, and a second Media-IXT cache upstream was a reverse proxy
for a RealNetworks origin server, problems sometimes occurred when the first cache requested content from
the second via PNA. Reverse proxy is not supported for PNA content; streaming PNA content in a reverse proxy
deployment should not be attempted.