Use this object to define the preference ordering of allowed SIP transports.
% set addressContext <name> zone <name> sipTrunkGroup <name> signaling transportPreference preference1 <none | sctp | tcp | tls-tcp | udp> preference2 <none | sctp | tcp | tls-tcp | udp> preference3 <none | sctp | tcp | tls-tcp | udp> preference4 <none | sctp | tcp | tls-tcp | udp>