Avaya DECT R4 Installation And Administration Manual page 267

Note:
Although it is possible to configure several codecs in the Communication
Note:
Manager IP-Codec-SET page, ensure that the first entry in the list in the Code list
and Media encryption list is equivalent to the Coder and the Secure RTP field
value in the IPBL/IPBS system because the IPBS/IPBL supports only one
protocol at a time.
For configuring SRTP on base station see,
Avaya DECT R4 - Installation and Maintenance Guide
Communication Manager system administration
Enabling SRTP on the base stations. on page 166
267
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