An extension to the SIP telephony protocol that carries the PSTN's ISUP call control messages between softswitches using the IP protocol. Also known as "SIP binary." See SIP and SS7.
"Interdomain SIP." YourDictionary, n.d. Web. 17 August 2018. <http://www.yourdictionary.com/interdomain-sip>.
Interdomain SIP. (n.d.). Retrieved August 17th, 2018, from http://www.yourdictionary.com/interdomain-sip