Specifications

RoadRunner USERS GUIDE
33
The Session
very session required the same three steps to be performed,
regardless of whether you will be making or receiving the call.
The first step is, of course, negotiating with the far-end user.
Determining what algorithm, bit and sample rates you want to use, and
who will make the call. The next step is configuring your RoadRunner,
and the last step is connecting.
This chapter will help you get through these three steps by discussing the
various configurations available, how to implement these configurations,
and finally, how to connect.
Encoder and Decoder Algorithms
Since no single algorithm is ideal for all applications, the RoadRunner
offers several different algorithm/sample rate/bit rate combinations,
each with advantages and disadvantages. In addition, the full range of
available algorithms insures that your RoadRunner can connect with
the widest number of codecs. The table below compares some of the
algorithm/sample rate/bit rate combinations that are available.
Recommended combinations are indicated with a 4.
Algorithm Sample
rate
Bit rate Bandwidth Delay Cascade
G.722 16 kHz 56/64 kb/s 7.5 kHz very low poor
MUSICAM 24 kHz 56/64 kb/s 10.2 kHz moderate good
4
MUSICAM 48 kHz 56/64 kb/s 8.5 kHz moderate fair
Chapter
7
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