---
title: RIST protocol
url: https://doc.pstreamer.tv/en/manual/rist.html
lang: en
product: Perfect Streamer
version: 1.13.3.445
---

# RIST protocol

New open protocol. Based on RTP/RTCP protocol. Works on the principle of Automatic Repeat reQuest (ARQ) without ACK, only NACK, that provides high efficiency.

Uses unicast and multicast.

Simple and Main profiles are implemented. Simple uses 2 udp ports in a row, the specified port must be even. Main uses only one RTP port with data multiplexing.

**On transmitter** — configured in output. For unicast, the receiver address and port are configured. For multicast, you need to set the network interface through which the data will be transmitted. Also for multicast you can set up receiver authorization by IP address by registering logins in **Peer**.

**On receiver** — endpoint is configured as input. For unicast mode, the receiver port (listen) is configured and the network interface is required. For multicast mode, only multicast group and port are set.

RIST supports several separate peers (addresses). If you set a weight (greater than 1), a load-balancing mode across peers according to the weight is enabled.

If the transmitter uses multicast, then there can be many receivers. In this case, it is possible to authenticate receivers by IP address. To do this, enable authentication in the transmitter settings (disabled by default) and add the client to the **Peer** list, enter the IP address in the login field.