Euresys 1669-DR Picolo.net HD1, Руководство пользователя

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RTP TRANSPORT MODALITIES
The following modalities are available to transport the RTP stream over an IP network:
RTP OVER UDP UNICAST
In this modality, the RTP stream is sent using the User Datagram Protocol - UDP - described in
RFC 768.
The UDP protocol is a "fire and forget" protocol. The sender sends the data through the network
and doesn't care whether that data arrives to the client or not. The data is never resent, and
thus can be lost if a problem happens during the transport.
In the Unicast mode, the sender sends the data to a single receiver.
RTP OVER UDP MULTICAST
This modality is almost identical to the "RTP over UDP Unicast" case. The only difference is that
the data is sent to multiple receivers instead of a single one using UDP multicasting.
UDP multicasting uses the "IP multicast" technique described in RFC 1112.
In this technique, the sender sends the data to a special multicast address. The data is then
sent by the routing protocols to receivers that previously informed the network that they are
interested in the given multicast address. IP multicast is thus a subscription-based technique.
RTP INTERLEAVED IN RTSP OVER HTTP
This modality is almost identical to the "RTP interleaved in RTSP over TCP" modality. The only
difference is that instead of being directly sent on the TCP stream, the RTP and RTSP packets
are first encapsulated in HTTP.
HTTP being a widely used protocol over the internet, encapsulating the data inside HTTP allows
it to pass through firewalls.
Moreover, encapsulating the data inside HTTP allows taking advantage of the TLS Protocol to
secure the media stream.
Since HTTP is based on TCP, this modality can also be categorized as reliable.
RTP TRANSPORT MEDIA TYPES
RTP can transport different media types, each coming with a corresponding sub-norm of RTP.
Picolo.net products implement the following sub-norms of RTP:
Functional Specifications Picolo.net Handbook