[xiph-commits] r12135 - trunk/vorbis/doc
lu_zero at svn.xiph.org
lu_zero at svn.xiph.org
Tue Nov 21 06:55:15 PST 2006
Author: lu_zero
Date: 2006-11-21 06:55:11 -0800 (Tue, 21 Nov 2006)
New Revision: 12135
Modified:
trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.xml
Log:
cleanup part 2
Modified: trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.xml
===================================================================
--- trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.xml 2006-11-21 14:16:08 UTC (rev 12134)
+++ trunk/vorbis/doc/draft-ietf-avt-rtp-vorbis-01.xml 2006-11-21 14:55:11 UTC (rev 12135)
@@ -283,23 +283,33 @@
</figure>
<t>
-Each Vorbis payload packet starts with a two octet length header, which is used to represent the size in bytes of the following data payload, followed by the raw Vorbis data padded to the nearest byte boundary. The length value is stored as network byte order integer.
+Each Vorbis payload packet starts with a two octet length header, which is used
+to represent the size in bytes of the following data payload, followed by the
+raw Vorbis data padded to the nearest byte boundary. The length value is stored
+as network byte order integer.
</t>
<t>
-For payloads which consist of multiple Vorbis packets the payload data consists of the packet length followed by the packet data for each of the Vorbis packets in the payload.
+For payloads which consist of multiple Vorbis packets the payload data consists
+of the packet length followed by the packet data for each of the Vorbis packets
+in the payload.
</t>
<t>
-The Vorbis packet length header is the length of the Vorbis data block only and does not count the length field.
+The Vorbis packet length header is the length of the Vorbis data block only and
+does not count the length field.
</t>
<t>
-The payload packing of the Vorbis data packets MUST follow the guidelines set-out in <xref target="rfc3551"></xref> where the oldest packet occurs immediately after the RTP packet header. Subsequent packets, if any, MUST follow in temporal order.
+The payload packing of the Vorbis data packets MUST follow the guidelines
+set-out in <xref target="rfc3551"></xref> where the oldest packet occurs
+immediately after the RTP packet header. Subsequent packets, if any, MUST
+follow in temporal order.
</t>
<t>
-Channel mapping of the audio is in accordance with the <xref target="vorbis-spec-ref">Vorbis I Specification</xref>.
+Channel mapping of the audio is in accordance with the
+<xref target="vorbis-spec-ref">Vorbis I Specification</xref>.
</t>
</section>
@@ -354,7 +364,11 @@
</figure>
<t>
-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 decode the packets is the one indexed by the ident value.
+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 decode the packets is the one indexed by the ident value.
</t>
</section>
@@ -382,9 +396,8 @@
</t>
<t>
-Thus these two codebook header packets must be received by the decoder
-before any audio data can be interpreted.
- These requirements pose problems in RTP,
+Thus these two codebook header packets must be received by the decoder before
+any audio data can be interpreted. These requirements pose problems in RTP,
which is often used over unreliable transports.
</t>
@@ -399,23 +412,43 @@
</t>
<t>
-The delivery vectors in use are specified by an SDP attribute to indicate the method and the optional URI where the Vorbis <xref target="Packed Configuration">Packed Configuration</xref> Packets could be fetched. Different delivery methods MAY be advertised for the same session. The in-band Configuration delivery SHOULD be considered as baseline, out-of-band delivery methods that don't use RTP will not be described in this document. For non chained streams, the Configuration recommended delivery method is inline the <xref target="Packed Configuration">Packed Configuration</xref> in the SDP as explained in the <xref target="Mapping MIME Parameters into SDP"> IANA considerations</xref> section.
+The delivery vectors in use are specified by an SDP attribute to indicate the
+method and the optional URI where the Vorbis
+<xref target="Packed Configuration">Packed Configuration</xref> Packets could
+be fetched. Different delivery methods MAY be advertised for the same session.
+The in-band Configuration delivery SHOULD be considered as baseline,
+out-of-band delivery methods that don't use RTP will not be described in this
+document. For non chained streams, the Configuration recommended delivery
+method is inline the <xref target="Packed Configuration">Packed Configuration</xref> in the SDP as explained in the <xref target="Mapping MIME Parameters into SDP"> IANA considerations</xref> section.
</t>
<t>
-The 24 bit Ident field is used to map which Configuration will be used to decode a packet. When the Ident field changes, it indicates 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.
+The 24 bit Ident field is used to map which Configuration will be used to
+decode a packet. When the Ident field changes, it indicates 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.
</t>
<section anchor="In-band Header Transmission" title="In-band Header Transmission">
<t>
-The <xref target="Packed Configuration">Packed Configuration</xref> Payload is sent in-band with the packet type bits set to match the Vorbis Data Type. Clients MUST be capable of dealing with fragmentation and periodic re-transmission of the configuration headers.
+The <xref target="Packed Configuration">Packed Configuration</xref> Payload is
+sent in-band with the packet type bits set to match the Vorbis Data Type.
+Clients MUST be capable of dealing with fragmentation and periodic
+re-transmission of the configuration headers.
</t>
<section anchor="Packed Configuration" title="Packed Configuration">
<t>
-A Vorbis Packed Configuration is indicated with the Vorbis Data Type field set to 1. Of the three headers, defined in the <xref target="vorbis-spec-ref">Vorbis I specification</xref>, the identification and the setup will be packed together, the comment header is completely suppressed. Is up to the client to provide a minimal size comment header to the decoder if required by the implementation.
+A Vorbis Packed Configuration is indicated with the Vorbis Data Type field set
+to 1. Of the three headers, defined in the
+<xref target="vorbis-spec-ref">Vorbis I specification</xref>, the
+identification and the setup will be packed together, the comment header is
+completely suppressed. Is up to the client to provide a minimal size comment
+header to the decoder if required by the implementation.
</t>
<figure anchor="Packed Configuration Figure" title="Packed Configuration Figure">
@@ -452,7 +485,9 @@
]]></artwork>
</figure>
-<t>The Ident field is set with the value that will be used by the Raw Payload Packets to address this Configuration. The Fragment type is set to 0 since the packet bears the full Packed configuration, the number of packet is set to 1.</t>
+<t>The Ident field is set with the value that will be used by the Raw Payload
+Packets to address this Configuration. The Fragment type is set to 0 since the
+packet bears the full Packed configuration, the number of packet is set to 1.</t>
</section>
</section>
@@ -460,13 +495,22 @@
<t>
-This section, as stated above, does not cover all the possible out-of-band delivery methods since they rely on different protocols and are linked to specific applications. The following packet definition SHOULD be used in out-of-band delivery and MUST be used when Configuration is inlined in the SDP.
+This section, as stated above, does not cover all the possible out-of-band
+delivery methods since they rely on different protocols and are linked to
+specific applications. The following packet definition SHOULD be used in
+out-of-band delivery and MUST be used when Configuration is inlined in the SDP.
</t>
<section anchor="Packed Headers" title="Packed Headers">
<t>
-As mentioned above the RECOMMENDED delivery vector for Vorbis configuration data is via a retrieval method that can be performed using a reliable transport protocol. As the RTP headers are not required for this method of delivery the structure of the configuration data is slightly different. The packed header starts with a 32 bit count field which details the number of packed headers that are contained in the bundle. Next is the Packed header payload for each chained Vorbis stream.
+As mentioned above the RECOMMENDED delivery vector for Vorbis configuration
+data is via a retrieval method that can be performed using a reliable transport
+protocol. As the RTP headers are not required for this method of delivery the
+structure of the configuration data is slightly different. The packed header
+starts with a 32 bit count field which details the number of packed headers
+that are contained in the bundle. Next is the Packed header payload for each
+chained Vorbis stream.
</t>
<figure anchor="Packed Headers Overview Figure" title="Packed Headers Overview">
@@ -484,7 +528,8 @@
</figure>
<t>
-Since the Configuration Ident and the Identification Header are fixed length there is only a 2 byte length tag to define the length of the packed headers.
+Since the Configuration Ident and the Identification Header are fixed length
+there is only a 2 byte length tag to define the length of the packed headers.
</t>
<figure anchor="Packed Headers Detail Figure" title="Packed Headers Detail">
@@ -505,7 +550,8 @@
]]></artwork>
</figure>
<t>
-The key difference between the in-band format and this one, is there is no need for the payload header octet.
+The key difference between the in-band format and this one, is there is no need
+for the payload header octet.
</t>
<section anchor="Packed Headers IANA Considerations" title="Packed Headers IANA Considerations">
@@ -623,11 +669,13 @@
<section anchor="Loss of Configuration Headers" title="Loss of Configuration Headers">
<t>
-Unlike the loss of raw Vorbis payload data, loss of a configuration header can lead to a situation where it will not be possible to successfully decode the stream.
+Unlike the loss of raw Vorbis payload data, loss of a configuration header can
+lead to a situation where it will not be possible to successfully decode the
+stream.
</t>
<t>
-Loss of Configuration Packet results in the halting of stream decoding
+Loss of Configuration Packet results in the halting of stream decoding.
</t>
</section>
@@ -637,7 +685,11 @@
<section anchor="Comment Headers" title="Comment Headers">
<t>
-With the Vorbis Data Type flag set to 2, this indicates that the packet contain the comment metadata, such as artist name, track title and so on. These metadata messages are not intended to be fully descriptive but to offer basic track/song information. Clients MAY ignore it completely. The details on the format of the comments can be found in the <xref target="vorbis-spec-ref">Vorbis documentation</xref>.
+With the Vorbis Data Type flag set to 2, this indicates that the packet contain
+the comment metadata, such as artist name, track title and so on. These
+metadata messages are not intended to be fully descriptive but to offer basic
+track/song information. Clients MAY ignore it completely. The details on the
+format of the comments can be found in the <xref target="vorbis-spec-ref">Vorbis documentation</xref>.
</t>
<figure anchor="Comment Packet Figure" title="Comment Packet">
<artwork><![CDATA[
@@ -665,27 +717,43 @@
]]></artwork>
</figure>
-<t>The 2 bytes length field is necessary since this packet could be fragmented.</t>
+<t>
+The 2 bytes length field is necessary since this packet could be fragmented.
+</t>
</section>
<section anchor="Frame Packetization" title="Frame Packetization">
<t>
-Each RTP packet contains either one Vorbis packet fragment, or an integer number of complete Vorbis packets (up to a maximum of 15 packets, since the number of packets is defined by a 4 bit value).
+Each RTP packet contains either one Vorbis packet fragment, or an integer
+number of complete Vorbis packets (up to a maximum of 15 packets, since the
+number of packets is defined by a 4 bit value).
</t>
<t>
-Any Vorbis data packet that is less than path MTU SHOULD be bundled in the RTP packet with as many Vorbis packets as will fit, up to a maximum of 15, except when such bundling would exceed an application's desired transmission latency. Path MTU is detailed in <xref target="rfc1063"></xref> and <xref target="rfc1981"></xref>.
+Any Vorbis data packet that is less than path MTU SHOULD be bundled in the RTP
+packet with as many Vorbis packets as will fit, up to a maximum of 15, except
+when such bundling would exceed an application's desired transmission latency.
+Path MTU is detailed in <xref target="rfc1063"></xref> and <xref target="rfc1981"></xref>.
</t>
<t>
-A fragmented packet has a zero in the last four bits of the payload header. The first fragment will set the Fragment type to 1. Each fragment after the first will set the Fragment type to 2 in the payload header. The RTP packet containing the last fragment of the Vorbis packet will have the Fragment type set to 3. To maintain the correct sequence for fragmented packet reception the timestamp field of fragmented packets MUST be the same as the first packet sent, with the sequence number incremented as normal for the subsequent RTP packets. The length field shows the fragment length.
+A fragmented packet has a zero in the last four bits of the payload header.
+The first fragment will set the Fragment type to 1. Each fragment after the
+first will set the Fragment type to 2 in the payload header. The RTP packet
+containing the last fragment of the Vorbis packet will have the Fragment type
+set to 3. To maintain the correct sequence for fragmented packet reception
+the timestamp field of fragmented packets MUST be the same as the first packet
+sent, with the sequence number incremented as normal for the subsequent RTP
+packets. The length field shows the fragment length.
</t>
<section anchor="Example Fragmented Vorbis Packet" title="Example Fragmented Vorbis Packet">
<t>
-Here is an example fragmented Vorbis packet split over three RTP packets. Each packet contains the standard RTP headers as well as the 4 octets Vorbis headers.
+Here is an example fragmented Vorbis packet split over three RTP packets.
+Each packet contains the standard RTP headers as well as the 4 octets Vorbis
+headers.
</t>
<figure anchor="Example Fragmented Packet (Packet 1)" title="Example Fragmented Packet (Packet 1)">
@@ -715,7 +783,8 @@
</figure>
<t>
-In this packet the initial sequence number is 1000 and the timestamp is xxxxx. The Fragment type is set to 1, the number of packets field is set to 0, and as the payload is raw Vorbis data the VDT field is set to 0.
+In this packet the initial sequence number is 1000 and the timestamp is xxxxx. The Fragment type is set to 1, the number of packets field is set to 0, and as
+the payload is raw Vorbis data the VDT field is set to 0.
</t>
<figure anchor="Example Fragmented Packet (Packet 2)" title="Example Fragmented Packet (Packet 2)">
@@ -745,7 +814,11 @@
</figure>
<t>
-The Fragment type field is set to 2 and the number of packets field is set to 0. For large Vorbis fragments there can be several of these type of payload packets. The maximum packet size SHOULD be no greater than the path MTU, including all RTP and payload headers. The sequence number has been incremented by one but the timestamp field remains the same as the initial packet.
+The Fragment type field is set to 2 and the number of packets field is set to 0.
+For large Vorbis fragments there can be several of these type of payload
+packets. The maximum packet size SHOULD be no greater than the path MTU,
+including all RTP and payload headers. The sequence number has been incremented
+by one but the timestamp field remains the same as the initial packet.
</t>
<figure anchor="Example Fragmented Packet (Packet 3)" title="Example Fragmented Packet (Packet 3)">
@@ -775,18 +848,31 @@
</figure>
<t>
-This is the last Vorbis fragment packet. The Fragment type is set to 3 and the packet count remains set to 0. As in the previous packets the timestamp remains set to the first packet in the sequence and the sequence number has been incremented.
+This is the last Vorbis fragment packet. The Fragment type is set to 3 and the
+packet count remains set to 0. As in the previous packets the timestamp remains
+set to the first packet in the sequence and the sequence number has been
+incremented.
</t>
</section>
<section anchor="Packet Loss" title="Packet Loss">
<t>
-As there is no error correction within the Vorbis stream, packet loss will result in a loss of signal. Packet loss is more of an issue for fragmented Vorbis packets as the client will have to cope with the handling of the Fragment Type. In case of loss of fragments the client MUST discard all the remaining fragments and decode the incomplete packet. If we use the fragmented Vorbis packet example above and the first packet is lost the client MUST detect that the next packet has the packet count field set to 0 and the Fragment type 2 and MUST drop it. The next packet, which is the final fragmented packet, MUST be dropped in the same manner. If the missing packet is the last, the received two fragments will be kept and the incomplete vorbis packet decoded.
+As there is no error correction within the Vorbis stream, packet loss will
+result in a loss of signal. Packet loss is more of an issue for fragmented
+Vorbis packets as the client will have to cope with the handling of the
+Fragment Type. In case of loss of fragments the client MUST discard all the
+remaining fragments and decode the incomplete packet. If we use the fragmented
+Vorbis packet example above and the first packet is lost the client MUST detect
+that the next packet has the packet count field set to 0 and the Fragment type
+2 and MUST drop it. The next packet, which is the final fragmented packet, MUST
+be dropped in the same manner. If the missing packet is the last, the received
+two fragments will be kept and the incomplete vorbis packet decoded.
</t>
<t>
-Loss of any of the Configuration fragment will result in the loss of the full Configuration packet with the result detailed in the <xref target="Loss of Configuration Headers">Loss of Configuration Headers</xref> section.
+Loss of any of the Configuration fragment will result in the loss of the full
+Configuration packet with the result detailed in the <xref target="Loss of Configuration Headers">Loss of Configuration Headers</xref> section.
</t>
</section>
@@ -837,7 +923,17 @@
<vspace blankLines="1" />
<list style="hanging">
-<t hangText="configuration-uri:"> the URI of the configuration headers in case of out of band transmission. In the form of "protocol://path/to/resource/". Depending on the specific method, a single configuration packet could be retrived by its number, or multiple packets could be aggregated in a single stream. Such aggregates MAY be compressed using either <xref target="BZ2">bzip2</xref> or <xref target="rfc1952">gzip</xref>. A <xref target="FIPS180">sha1</xref> checksum MAY be provided for aggregates. In this latter case the URI will end with the aggregate name, followed by its compressed extension if applies, a "!" and the hexadecimal representation of the sha1hash of the above mentioned compressed aggregatedas in: "protocol://path/to/resource/aggregated.bz2!sha1hash".</t>
+<t hangText="configuration-uri:"> the URI of the configuration headers in case
+of out of band transmission. In the form of "protocol://path/to/resource/".
+Depending on the specific method, a single configuration packet could be
+retrived by its number, or multiple packets could be aggregated in a single
+stream. Such aggregates MAY be compressed using either
+<xref target="BZ2">bzip2</xref> or <xref target="rfc1952">gzip</xref>.
+A <xref target="FIPS180">sha1</xref> checksum MAY be provided for aggregates.
+In this latter case the URI will end with the aggregate name, followed by its
+compressed extension if applies, a "!" and the hexadecimal representation of
+the sha1hash of the above mentioned compressed aggregatedas in:
+"protocol://path/to/resource/aggregated.bz2!sha1hash". The trailing '/' discriminates which of two methods are in use.</t>
</list>
</t>
@@ -921,7 +1017,9 @@
<section anchor="Mapping MIME Parameters into SDP" title="Mapping MIME Parameters into SDP">
<t>
-The information carried in the MIME media type specification has a specific mapping to fields in the Session Description Protocol (SDP) <xref target="rfc2327"></xref>, which is commonly used to describe RTP sessions. When SDP is used to specify sessions the mapping are as follows:
+The information carried in the MIME media type specification has a specific
+mapping to fields in the Session Description Protocol (SDP) <xref target="rfc2327"></xref>, which is commonly used to describe RTP sessions. When SDP is used
+to specify sessions the mapping are as follows:
</t>
<vspace blankLines="1" />
@@ -939,27 +1037,41 @@
<t>The parameter "channels" also goes in "a=rtpmap" as channel count.</t>
<vspace blankLines="1" />
-<t>The mandated parameters "delivery-method" and "configuration" MUST be included in the SDP "a=fmpt" attribute.</t>
+<t>The mandated parameters "delivery-method" and "configuration" MUST be
+included in the SDP "a=fmpt" attribute.</t>
<vspace blankLines="1" />
-<t>The optional parameter "configuration-uri", when present, MUST be included in the SDP "a=fmpt" attribute and MUST follow the delivery-method that applies.</t>
+<t>The optional parameter "configuration-uri", when present, MUST be included
+in the SDP "a=fmpt" attribute and MUST follow the delivery-method that applies.</t>
</list>
<t>
-If the stream comprises chained Vorbis files and all of them are known in advance, the Configuration Packet for each file SHOULD be passed to the client using the configuration attribute.
+If the stream comprises chained Vorbis files and all of them are known in
+advance, the Configuration Packet for each file SHOULD be passed to the client
+using the configuration attribute.
</t>
<t>
-The URI specified in the configuration-uri attribute MUST point to a location where all of the Configuration Packets needed for the life of the session reside.
+The URI specified in the configuration-uri attribute MUST point to a location
+where all of the Configuration Packets needed for the life of the session
+reside.
</t>
<t>
-The port value is specified by the server application bound to the address specified in the c attribute. The bitrate value and channels specified in the rtpmap attribute MUST match the Vorbis sample rate value. An example is found below.
+The port value is specified by the server application bound to the address
+specified in the c attribute. The bitrate value and channels specified in the
+rtpmap attribute MUST match the Vorbis sample rate value. An example is found
+below.
</t>
<section anchor="SDP Example" title="SDP Example">
-<t>The following example shows a basic SDP single stream. The first configuration packet is inlined in the sdp, other configurations could be fetched at any time from the first provided uri using or all the known configuration could be downloaded using the second uri. The inline <xref target="rfc3548">base16</xref> configuration string is omitted because of the lenght.</t>
+<t>The following example shows a basic SDP single stream. The first
+configuration packet is inlined in the sdp, other configurations could be
+fetched at any time from the first provided uri using or all the known
+configuration could be downloaded using the second uri. The inline
+<xref target="rfc3548">base16</xref> configuration string is omitted because of
+the lenght.</t>
<list style="empty">
<t>c=IN IP4 192.0.0.1</t>
@@ -971,7 +1083,13 @@
<t>
-Note that the payload format (encoding) names are commonly shown in upper case. MIME subtypes are commonly shown in lower case. These names are case-insensitive in both places. Similarly, parameter names are case-insensitive both in MIME types and in the default mapping to the SDP a=fmtp attribute. The exception regarding case sensitivity is the configuration-uri URI which MUST be regarded as being case sensitive.
+Note that the payload format (encoding) names are commonly shown in upper case.
+MIME subtypes are commonly shown in lower case. These names are
+case-insensitive in both places. Similarly, parameter names are
+case-insensitive both in MIME types and in the default mapping to the SDP
+a=fmtp attribute. The exception regarding case sensitivity is the
+configuration-uri URI which MUST be regarded as being case sensitive. The
+a=fmtp line is a single line even if it is presented broken because of clarity.
</t>
</section>
@@ -979,7 +1097,11 @@
<section anchor="Usage with the SDP Offer/Answer Mode" title="Usage with the SDP Offer/Answer Model">
<t>
-The offer, as described in <xref target="rfc3264">An Offer/Answer Model Session Description Protocol</xref>, may contain a large number of delivery methods per single fmtp attribute, the answerer MUST remove every delivery-method and configuration-uri not supported. All the parameters MUST not be altered on answer otherwise.
+The offer, as described in <xref target="rfc3264">An Offer/Answer Model Session
+Description Protocol</xref>, may contain a large number of delivery methods per
+single fmtp attribute, the answerer MUST remove every delivery-method and
+configuration-uri not supported. All the parameters MUST not be altered on
+answer otherwise.
</t>
</section>
@@ -989,7 +1111,11 @@
<section anchor="Congestion Control" title="Congestion Control">
<t>
-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 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.
+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 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.
</t>
</section>
@@ -997,34 +1123,55 @@
<section anchor="Examples" title="Examples">
<t>
-The following examples are common usage patterns that MAY be applied in such situations, the main scope of this section is to explain better usage of the transmission vectors.
+The following examples are common usage patterns that MAY be applied in such
+situations, the main scope of this section is to explain better usage of the
+transmission vectors.
</t>
<section anchor="Stream Radio" title="Stream Radio">
-<t>This is one of the most common situation: one single server streaming content in multicast, the clients may start a session at random time. The content itself could be a mix of live stream, as the wj's voice, and stored streams as the music she plays.</t>
+<t>This is one of the most common situation: one single server streaming
+content in multicast, the clients may start a session at random time. The
+content itself could be a mix of live stream, as the wj's voice, and stored
+streams as the music she plays.</t>
-<t>In this situation we don't know in advance how many codebooks we will use. The clients can join anytime and users expect to start listening to the content in a short time.</t>
+<t>In this situation we don't know in advance how many codebooks we will use.
+The clients can join anytime and users expect to start listening to the content
+in a short time.</t>
-<t>On join the client will receive the current Configuration necessary to decode the current stream inlined in the SDP so that the decoding will start immediately after.</t>
+<t>On join the client will receive the current Configuration necessary to
+decode the current stream inlined in the SDP so that the decoding will start
+immediately after.</t>
-<t>When the streamed content changes the new Configuration is sent in-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.</t>
+<t>When the streamed content changes the new Configuration is sent in-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.</t>
-<t>The client could choose to fetch the Configuration from the alternate source as soon it discovers a Configuration packet got lost in-band or use <xref target="RFC3611">selective retransmission</xref>, if the server supports the feature.</t>
+<t>The client could choose to fetch the Configuration from the alternate source
+as soon it discovers a Configuration packet got lost in-band or use
+<xref target="RFC3611">selective retransmission</xref>, if the server supports
+the feature.</t>
-<t>A serverside optimization would be to keep an hash list of the Configurations per session to avoid packing all of them and send the same Configuration with different Ident tags</t>
+<t>A serverside optimization would be to keep an hash list of the
+Configurations per session to avoid packing all of them and send the same
+Configuration with different Ident tags</t>
-<t>A clientside optimization would be to keep a tag list of the Configurations per session and don't process configuration packets already known.</t>
+<t>A clientside optimization would be to keep a tag list of the Configurations
+per session and don't process configuration packets already known.</t>
</section>
</section>
<section anchor="Security Considerations" title="Security Considerations">
<t>
-RTP packets using this payload format are subject to the security considerations discussed in the RTP specification
-<xref target="rfc3550"></xref>. This implies that the confidentiality of the media stream is achieved by using
-encryption. Because the data compression used with this payload format is applied end-to-end, encryption may be performed on the
-compressed data. Where the size of a data block is set care MUST be taken to prevent buffer overflows in the client applications.
+RTP packets using this payload format are subject to the security
+considerations discussed in the RTP specification
+<xref target="rfc3550"></xref>. This implies that the confidentiality of the
+media stream is achieved by using encryption. Because the data compression used
+with this payload format is applied end-to-end, encryption may be performed on
+the compressed data. Where the size of a data block is set care MUST be taken
+to prevent buffer overflows in the client applications.
</t>
</section>
@@ -1032,11 +1179,19 @@
<section anchor="Acknowledgments" title="Acknowledgments">
<t>
-This document is a continuation of draft-moffitt-vorbis-rtp-00.txt and draft-kerr-avt-vorbis-rtp-04.txt. The MIME type section is a continuation of draft-short-avt-rtp-vorbis-mime-00.txt.
+This document is a continuation of draft-moffitt-vorbis-rtp-00.txt and
+draft-kerr-avt-vorbis-rtp-04.txt. The MIME type section is a continuation of
+draft-short-avt-rtp-vorbis-mime-00.txt.
</t>
<t>
-Thanks to the AVT, Ogg Vorbis Communities / Xiph.org including Steve Casner, Aaron Colwell, Ross Finlayson, Fluendo, Ramon Garcia, Pascal Hennequin, Ralph Giles, Tor-Einar Jarnbjo, Colin Law, John Lazzaro, Jack Moffitt, Christopher Montgomery, Colin Perkins, Barry Short, Mike Smith, Phil Kerr, Michael Sparks, Magnus Westerlund, David Barrett, Silvia Pfeiffer, Stefan Ehmann, Alessandro Salvatori. Politecnico di Torino (LS)³/IMG Group in particular Federico Ridolfo, Francesco Varano, Giampaolo Mancini, Juan Carlos De Martin.
+Thanks to the AVT, Ogg Vorbis Communities / Xiph.org including Steve Casner,
+Aaron Colwell, Ross Finlayson, Fluendo, Ramon Garcia, Pascal Hennequin, Ralph
+Giles, Tor-Einar Jarnbjo, Colin Law, John Lazzaro, Jack Moffitt, Christopher
+Montgomery, Colin Perkins, Barry Short, Mike Smith, Phil Kerr, Michael Sparks,
+Magnus Westerlund, David Barrett, Silvia Pfeiffer, Stefan Ehmann, Alessandro
+Salvatori. Politecnico di Torino (LS)³/IMG Group in particular Federico
+Ridolfo, Francesco Varano, Giampaolo Mancini, Juan Carlos De Martin.
</t>
</section>
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