Nortel Networks WEB OS 212777 - Manual (Page 156)

Web OS 10.0 Application Guide
156 n Chapter 6: Server Load Balancing
212777-A, February 2002
Corporation, and Quicktime Streaming Server marketed by the Apple Inc. The RTSP stream
setup sequence is different for these two servers, and the switch handles each differently. Some
of these differences are described below.
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Real Server
Real Server supports both UDP and TCP transport protocols for the RTSP streams. The
actual transport is negotiated during the initialization of the connection. If TCP transport is
selected, then all streams of data will flow in the TCP control connection itself. If UDP
transport is chosen, the client and server negotiate a client UDP port, which is manually
configurable.
The real media files that the Real Server plays have the extension “.rm”, “.ram” or “.smil”.
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QuickTime Streaming Server
Apple Inc.’s QuickTime Streaming Server typically runs on the Apple platforms. Quick-
Time files that can be played over the Internet using RTSP are specially formatted and are
called “hinted QuickTime files.” Normal QuickTime files cannot be used for streaming.
The QuickTime files have the extension “.mov”.
QuickTime uses UDP protocol exclusively for transport and TCP for control connection.
Each stream of a QuickTime presentation sends Real Time Protocol (RTP), and Real Time
Control Protocol (RTCP) data using two UDP connections. Typically, a QuickTime pre-
sentation has two streams and therefore uses four UDP connections and one TCP control
connection. QuickTime clients use a UDP port, which is manually configurable.
RTSP Implementation
RTSP implementation in Web OS supports the following:
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Alteon AD3, Alteon AD4, Alteon 180e, and Alteon 184 platforms
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Private addressing on the server side
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Layer 7 URL-hashing metric, URL pattern matching, and all Layer 4 metrics for load bal-
ancing.
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All the stream connections and the control connections are switched to the same cache
server to facilitate caching of entire presentations.
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RTSP-compliant applications (excludes Windows Media Player because it is not RTSP
compliant).