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<param name="sip-ip" value="$${local_ip_v4_or_v6}"/>
Alternatively, since version 1.6 it is possible to specify an interface and an optionnal address family instead of an IP, same for rtp-ip.
<param name="sip-ip" value="interface:[auto|ipv4|ipv6|]/eth0"/>
rtp-ip
IP address to bind to for RTP traffic. DO NOT USE HOSTNAMES, ONLY IP ADDRESSES
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