VBrick dme, Руководство администратора

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O u t - 7 > R e la y ( Un ic a s t /M u lt ic a s t )
Relays can be used to output RTP streams as either unicast or multicast. However, it is
normally used for multicast, since pushing RTP should use OUT-10 whenever possible. As
explained below, after configuring the stream source, there are two ways to configure the
relay destination. You can (1) configure an Announced UDP relay where the stream is
announced and transmitted via Auto Unicast (Out-11); or (2) configure an Unannounced
UDP relay where the destination device requires access to the sdp file located on the source
DME.
The use case for Auto Unicast is not recommended—use Out-11 instead, a similar use case.
Details are covered in Out-10 > Push RTP via RTSP below. If using Unannounced relay with
a unicast destination the sdp file may have to be manually copied the from the source to the
destination - an error prone and inconvenient process. It is occasionally necessary to use this
technique to communicate with an end device depending on firewall settings. The dominant
use for the Relay configuration is to generate an RTP multicast. Typically the sdp file is
accessed via HTTP. The sdp file contains all of the information needed for the client to
locate the multicast. Each of these options is explained below. See RTP Relay Overview for
more about relays.
Figure 1. RTP Relay Page
Source Settings
Every relay has one source and one or more destinations. The source is typically the
Hostname or IP address of the DME.
Tip : For a step-by-step procedure that explains how to configure a multicast
relay in greater detail, see Play a DME Stream.