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Gateway Configuration
Figure 25-1: Gateways between IP and CS contexts
25.2 Gateway Configuration Task List
This chapter describes the configuration of the H.323 and IsoIP gateways. Some parameters could be
configured in the gateway configuration mode and overwritten in another configuration mode. For
example the default value for the voice codec for ISoIP connections is set in the gateway
configuration mode and could be overwritten in the ISoIP interface.
All
possible configurations
which are involved in a specific configuration topic are described in the respective configuration
task. There are some differences between the ISoIP and H.323 gateway. If it is not otherwise stated,
the configuration task is valid for both gateways.
•
Configure Codec Selection and Fast Connect
•
Configure Registration Authentication Service (RAS) in an H.323 Gateway (Advanced)
•
Enable Q.931 tunneling for an H.323 connection (Advanced)
•
Show and Enable the Gateway Configuration
25.3 Configure Codec Selection and Fast Connect
25.3.1 Introduction
Voice channels occupy 64 kbps using PCM (pulse code modulation) coding. Over the years,
compression techniques have been developed allowing a reduction in the required bandwidth while
preserving voice quality. Such techniques are implemented as 'codecs'. Although many proprietary
compression schemes exist, most H.323 devices today use codecs that were standardized by bodies
such as the ITU-T for the sake of interoperability across vendors. Different compression schemes can
be compared using four parameters:
•
Compressed voice rate – the codec compresses voice from 64 kbps down to a certain bit rate.
Some network designs have a preference for low-bit-rate codecs. Most codecs can
Software Configuration Guide, Revision 1.03
Summary of Contents for SmartWare R2.00
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