Documents by E. Ivov
2011, RFC6464: A Real-time Transport Protocol (RTP) Header Extension for Client-to-Mixer Audio Level Indication
2011, RFC6465: A Real-time Transport Protocol (RTP) Header Extension for Mixer-to-Client Audio Level Indication
2013, RFC7081: CUSAX: Combined Use of the Session Initiation Protocol (SIP) and the Extensible Messaging and Presence Protocol (XMPP)
2014, RFC7106: A Group Text Chat Purpose for Conference and Service URIs in the SIP Event Package for Conference State