MINE lab ZTE Corporation MINE lab ZTE Corporation MINE lab ALTO has been proposed to help peer-to-peer (P2P) applications make better decisions with respect to peer selection. It provides the underlying network view for P2P users to choose the optimal resource instances. The usage of ALTO has covered nearly all the P2P applications, such as file sharing, media streaming, real time communications and etc. In real time communication where the source and destination are fixed, it is used to choose relays. This document defines the relay usage for ALTO in real time communication. Beside the relay for NAT traversal mentioned before, this document introduce a relay called Qos relay to improve the performance. After analyzing the necessity of this type of relay and the benefits of combining ALTO with relay, two models of combination are described according to the coupling tightness between ALTO and relay service. One is called "integrating relay service into alto service" and the other is "cooperation between P2P application provider and ISP". In all, the usage of ALTO in real time communication has been developed in this document.