8. Congestion Control . . . . . . . . . . . . . . . . . . . . . . 21
9. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
9.1. Stream Radio . . . . . . . . . . . . . . . . . . . . . . . 22
- 10. Security Considerations . . . . . . . . . . . . . . . . . . . 23
+ 10. Security Considerations . . . . . . . . . . . . . . . . . . . 22
11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 23
12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 23
12.1. Normative References . . . . . . . . . . . . . . . . . . . 23
Here is an example RTP packet containing two Vorbis packets.
- RTP Packet Header:
-
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The payload data section of the RTP packet begins with the 24 bit
Ident field followed by the one octet bitfield header, which has the
number of Vorbis frames set to 2. Each of the Vorbis data frames is
+ prefixed by the two octets length field. The Packet Type and
+ Fragment Type are set to 0. The Configuration that will be used to
Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 2007
- prefixed by the two octets length field. The Packet Type and
- Fragment Type are set to 0. The Configuration that will be used to
decode the packets is the one indexed by the ident value.
that a change in the stream has taken place. The client application
MUST have in advance the correct configuration and if the client
detects a change in the Ident value and does not have this
+ information it MUST NOT decode the raw Vorbis data associated until
+ it fetches the correct Configuration.
Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 2007
- information it MUST NOT decode the raw Vorbis data associated until
- it fetches the correct Configuration.
-
3.1. In-band Header Transmission
The Packed Configuration (Section 3.1.1) Payload is sent in-band with
+
+
+
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a=fmtp:98 delivery-method=inline;
configuration=AAAAAZ2f4g9NAh4aAXZvcmJpcwA...; delivery-
method=out_band; configuration-uri=rtsp://path/to/the/resource;
- delivery-method=out_band; configuration-uri=http://another/path/
- to/resource/
- aggregate.bz2!8b6237eb5154a0ea12811a94e8e2697b3312bc6c;
+ delivery-method=out_band;
+ configuration-uri=http://another/path/to/resource/;
Note that the payload format (encoding) names are commonly shown in
upper case. Media Type subtypes are commonly shown in lower case.
Vorbis clients SHOULD send regular receiver reports detailing
congestion. A mechanism for dynamically downgrading the stream,
+ known as bitrate peeling, will allow for a graceful backing off of
Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 2007
- known as bitrate peeling, will allow for a graceful backing off of
the stream bitrate. This feature is not available at present so an
alternative would be to redirect the client to a lower bitrate stream
if one is available.
will start immediately after.
When the streamed content changes the new Configuration is sent in-
- band before the actual stream, and the Configuration that has to be
+ band before the actual stream and the Configuration that has to be
sent inline in the SDP updated. Since the in-band method is
unreliable, an out of band fallback is provided.
- The client could choose to fetch the Configuration from the alternate
+ The client MAY choose to fetch the Configuration from the alternate
source as soon as it discovers a Configuration packet got lost in-
band or use selective retransmission [13], if the server supports the
feature.
already known.
+10. Security Considerations
-
+ RTP packets using this payload format are subject to the security
Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 2007
-10. Security Considerations
-
- RTP packets using this payload format are subject to the security
considerations discussed in the RTP specification [2]. This implies
that the confidentiality of the media stream is achieved by using
encryption. Because the data compression used with this payload
Resource Identifier (URI): Generic Syntax", RFC 3986.
[5] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
+ Description Protocol", RFC 4566, July 2006.
+
+ [6] Mogul, J. and S. Deering, "Path MTU discovery", RFC 1191,
Internet-Draft draft-ietf-avt-rtp-vorbis-06 Jun 2007
- Description Protocol", RFC 4566, July 2006.
-
- [6] Mogul, J. and S. Deering, "Path MTU discovery", RFC 1191,
November 1990.
[7] McCann et al., J., "Path MTU Discovery for IP version 6",
+
+
+
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Here is an example RTP packet containing two Vorbis packets.
</t>
-<t>
-RTP Packet Header:
-</t>
-
<figure anchor="Example Raw Vorbis Packet" title="Example Raw Vorbis Packet">
<artwork><
projects / platform / upstream / libvorbis.git / commitdiff