draft-ietf-httpbis-rand-access-live-02.txt   draft-ietf-httpbis-rand-access-live-latest.txt 
HTTP Working Group C. Pratt HTTP Working Group C. Pratt
Internet-Draft CableLabs Internet-Draft
Intended status: Experimental B. Stark Intended status: Experimental B. Stark
Expires: May 18, 2018 AT&T Expires: May 5, 2018 AT&T
D. Thakore D. Thakore
CableLabs CableLabs
November 14, 2017 November 2017
HTTP Random Access and Live Content HTTP Random Access and Live Content
draft-ietf-httpbis-rand-access-live-02 draft-ietf-httpbis-rand-access-live-latest
Abstract Abstract
To accommodate byte range requests for content that has data appended To accommodate byte range requests for content that has data appended
over time, this document defines semantics that allow a HTTP client over time, this document defines semantics that allow a HTTP client
and server to perform byte-range GET and HEAD requests that start at and server to perform byte-range GET and HEAD requests that start at
an arbitrary byte offset within the representation and ends at an an arbitrary byte offset within the representation and ends at an
indeterminate offset. indeterminate offset.
Editorial Note (To be removed by RFC Editor before publication) Editorial Note (To be removed by RFC Editor before publication)
skipping to change at page 1, line 47 skipping to change at page 1, line 47
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on May 18, 2018. This Internet-Draft will expire on May 5, 2018.
Copyright Notice Copyright Notice
Copyright (c) 2017 IETF Trust and the persons identified as the Copyright (c) 2017 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Provisions Relating to IETF Documents Provisions Relating to IETF Documents
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publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
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the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
1.2. Notational Conventions . . . . . . . . . . . . . . . . . 3
2. Performing Range requests on Random-Access Aggregating 2. Performing Range requests on Random-Access Aggregating
("live") Content . . . . . . . . . . . . . . . . . . . . . . 3 ("live") Content . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Establishing the Randomly Accessible Byte Range . . . . . 4 2.1. Establishing the Randomly Accessible Byte Range . . . . . 4
2.2. Byte-Range Requests Beyond the Randomly Accessible Byte 2.2. Byte-Range Requests Beyond the Randomly Accessible Byte
Range . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Range . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Other Applications of Random-Access Aggregating Content . . . 7 3. Other Applications of Random-Access Aggregating Content . . . 7
3.1. Requests Starting at the Aggregation ("Live") Point . . . 7 3.1. Requests Starting at the Aggregation ("Live") Point . . . 7
3.2. Shift Buffer Representations . . . . . . . . . . . . . . 7 3.2. Shift Buffer Representations . . . . . . . . . . . . . . 8
4. Security Considerations . . . . . . . . . . . . . . . . . . . 8 4. Security Considerations . . . . . . . . . . . . . . . . . . . 9
5. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 5. References . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.1. Normative References . . . . . . . . . . . . . . . . . . 9 5.1. Normative References . . . . . . . . . . . . . . . . . . 9
5.2. Informative References . . . . . . . . . . . . . . . . . 9 5.2. Informative References . . . . . . . . . . . . . . . . . 10
Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 9 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10
1. Introduction 1. Introduction
Some Hypertext Transfer Protocol (HTTP) clients use byte-range Some Hypertext Transfer Protocol (HTTP) clients use byte-range
requests (Range requests using the "bytes" Range Unit) to transfer requests (Range requests using the "bytes" Range Unit) to transfer
select portions of large representations. And in some cases large select portions of large representations ([RFC7233]). And in some
representations require content to be continuously or periodically cases large representations require content to be continuously or
appended - such as representations consisting of live audio or video periodically appended - such as representations consisting of live
sources, blockchain databases, and log files. Clients cannot access audio or video sources, blockchain databases, and log files. Clients
the appended/live content using a Range request with the bytes range cannot access the appended/live content using a Range request with
unit using the currently defined byte-range semantics without the bytes range unit using the currently defined byte-range semantics
accepting performance or behavior sacrifices which are not acceptable without accepting performance or behavior sacrifices which are not
for many applications. acceptable for many applications.
For instance, HTTP clients have the ability to access appended For instance, HTTP clients have the ability to access appended
content on an indeterminate-length resource by transferring the content on an indeterminate-length resource by transferring the
entire representation from the beginning and continuing to read the entire representation from the beginning and continuing to read the
appended content as it's made available. Obviously, this is highly appended content as it's made available. Obviously, this is highly
inefficient for cases where the representation is large and only the inefficient for cases where the representation is large and only the
most recently appended content is needed by the client. most recently appended content is needed by the client.
Alternatively, clients can also access appended content by sending Alternatively, clients can also access appended content by sending
periodic open-ended bytes Range requests using the last-known end periodic open-ended bytes Range requests using the last-known end
byte position as the range start. Performing low-frequency periodic byte position as the range start. Performing low-frequency periodic
bytes Range requests in this fashion (polling) introduces latency bytes Range requests in this fashion (polling) introduces latency
since the client will necessarily be somewhat behind the aggregated since the client will necessarily be somewhat behind the aggregated
content - mimicking the behavior (and latency) of segmented content content - mimicking the behavior (and latency) of segmented content
representations such as HLS or MPEG-DASH. And while performing these representations such as "HTTP Live Streaming" (HLS, [RFC8216]) or
Range requests at higher frequency can reduce this latency, it also "Dynamic Adaptive Streaming over HTTP" (MPEG-DASH, [DASH]). And
incurs more processing overhead and HTTP exchanges as many of the while performing these Range requests at higher frequency can reduce
requests will return no content - since content is usually aggregated this latency, it also incurs more processing overhead and HTTP
in groups of bytes (e.g. a video frame, audio sample, block, or log exchanges as many of the requests will return no content - since
entry). content is usually aggregated in groups of bytes (e.g. a video frame,
audio sample, block, or log entry).
This document describes a usage model for range requests which This document describes a usage model for range requests which
enables efficient retrieval of representations that are appended to enables efficient retrieval of representations that are appended to
over time by using large values and associated semantics for over time by using large values and associated semantics for
communicating range end positions. This model allows representations communicating range end positions. This model allows representations
to be progressively delivered by servers as new content is added. It to be progressively delivered by servers as new content is added. It
also ensures compatibility with servers and intermediaries that don't also ensures compatibility with servers and intermediaries that don't
support this technique. support this technique.
1.1. Requirements Language 1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
1.2. Notational Conventions
This document cites productions in Augmented Backus-Naur Form (ABNF)
productions from [RFC7233], using the notation defined in [RFC5234].
2. Performing Range requests on Random-Access Aggregating ("live") 2. Performing Range requests on Random-Access Aggregating ("live")
Content Content
This document recommends a two-step process for accessing resources This document recommends a two-step process for accessing resources
that have indeterminate length representations. Two steps are that have indeterminate length representations.
necessary because of limitations with the Range request header and
the Content-Range response header fields. A server cannot know from Two steps are necessary because of limitations with the Range request
a range request that a client wishes to receive a response that does header and the Content-Range response header fields. A server cannot
not have a definite end. More critically, the header fields do not know from a range request that a client wishes to receive a response
allow the server to signal that a resource has indeterminate length that does not have a definite end. More critically, the header
without also providing a fixed portion of the resource. A client fields do not allow the server to signal that a resource has
first learns that the resource has a representation of indeterminate indeterminate length without also providing a fixed portion of the
length by requesting a range of the resource. The server responds resource.
with the range that is available, but indicates that the length of
the representation is unknown using the existing Content-Range A client first learns that the resource has a representation of
syntax. See Section 2.1 for details and examples. Once the client indeterminate length by requesting a range of the resource. The
knows the resource has indeterminate length, it can request a range server responds with the range that is available, but indicates that
with a very large end position from the resource. The client chooses the length of the representation is unknown using the existing
an explicit end value larger than can be transferred in the Content-Range syntax. See Section 2.1 for details and examples.
foreseeable term. A server which supports range requests of
indeterminate length signals its understanding of the client's Once the client knows the resource has indeterminate length, it can
indeterminate range request by indicating that the range it is request a range with a very large end position from the resource.
providing has a range end that exactly matches the client's requested The client chooses an explicit end value larger than can be
range end rather than a range that is bounded by what is currently transferred in the foreseeable term. A server which supports range
available. See Section 2.2 for details. requests of indeterminate length signals its understanding of the
client's indeterminate range request by indicating that the range it
is providing has a range end that exactly matches the client's
requested range end rather than a range that is bounded by what is
currently available. See Section 2.2 for details.
2.1. Establishing the Randomly Accessible Byte Range 2.1. Establishing the Randomly Accessible Byte Range
Establishing if a representation is continuously aggregating ("live") Establishing if a representation is continuously aggregating ("live")
and determining the randomly-accessible byte range can both be and determining the randomly-accessible byte range can both be
determined using the existing definition for an open-ended byte-range determined using the existing definition for an open-ended byte-range
request. Specifically, [RFC7233] defines a byte-range request of the request. Specifically, Section 2.1 of [RFC7233] defines a byte-range
form: request of the form:
byte-range-spec = first-byte-pos "-" [ last-byte-pos ] byte-range-spec = first-byte-pos "-" [ last-byte-pos ]
which allows a client to send a HEAD request with a first-byte-pos which allows a client to send a HEAD request with a first-byte-pos
and leave last-byte-pos absent. A server that receives a satisfiable and leave last-byte-pos absent. A server that receives a satisfiable
byte-range request (with first-byte-pos smaller than the current byte-range request (with first-byte-pos smaller than the current
representation length) may respond with a 206 status code (Partial representation length) may respond with a 206 status code (Partial
Content) with a Content-Range header indicating the currently Content) with a Content-Range header indicating the currently
satisfiable byte range. For example: satisfiable byte range. For example:
HEAD /resource HTTP/1.1 HEAD /resource HTTP/1.1
Range: bytes=0- Host: example.com
Range: bytes=0-
returns a response of the form: returns a response of the form:
HTTP/1.1 206 Partial Content HTTP/1.1 206 Partial Content
Content-Range: bytes 0-1234567/* Content-Range: bytes 0-1234567/*
from the server indicating that (1) the complete representation from the server indicating that (1) the complete representation
length is unknown (via the "*" in place of the complete-length field) length is unknown (via the "*" in place of the complete-length field)
and (2) that only bytes 0-1234567 were accessable at the time the and (2) that only bytes 0-1234567 were accessable at the time the
request was processed by the server. The client can infer from this request was processed by the server. The client can infer from this
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an indefinite "live" point - a point where the byte-range GET request an indefinite "live" point - a point where the byte-range GET request
is fulfilled on-demand as the content is aggregated. is fulfilled on-demand as the content is aggregated.
For example, for a large video asset, a client may wish to start a For example, for a large video asset, a client may wish to start a
content transfer from the video "key" frame immediately before the content transfer from the video "key" frame immediately before the
point of aggregation and continue the content transfer indefinitely point of aggregation and continue the content transfer indefinitely
as content is aggregated - in order to support low-latency startup of as content is aggregated - in order to support low-latency startup of
a live video stream. a live video stream.
Unlike a byte-range Range request, a byte-range Content-Range Unlike a byte-range Range request, a byte-range Content-Range
response header cannot be "open ended", per [RFC7233]: response header cannot be "open ended", per Section 4.2 of [RFC7233]:
byte-content-range = bytes-unit SP byte-content-range = bytes-unit SP
( byte-range-resp / unsatisfied-range ) ( byte-range-resp / unsatisfied-range )
byte-range-resp = byte-range "/" ( complete-length / "*" ) byte-range-resp = byte-range "/" ( complete-length / "*" )
byte-range = first-byte-pos "-" last-byte-pos byte-range = first-byte-pos "-" last-byte-pos
unsatisfied-range = "*/" complete-length unsatisfied-range = "*/" complete-length
complete-length = 1*DIGIT complete-length = 1*DIGIT
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to indicate support for handling an indeterminate-length byte-range to indicate support for handling an indeterminate-length byte-range
response, and a mechanism for a server to indicate if/when it's response, and a mechanism for a server to indicate if/when it's
providing a indeterminate-length response. providing a indeterminate-length response.
A client can indicate support for handling indeterminate-length byte- A client can indicate support for handling indeterminate-length byte-
range responses by providing a Very Large Value for the last-byte-pos range responses by providing a Very Large Value for the last-byte-pos
in the byte-range request. For example, a client can perform a byte- in the byte-range request. For example, a client can perform a byte-
range GET request of the form: range GET request of the form:
GET /resource HTTP/1.1 GET /resource HTTP/1.1
Host: example.com
Range: bytes=1230000-999999999999 Range: bytes=1230000-999999999999
where the last-byte-pos in the Request is much larger than the last- where the last-byte-pos in the Request is much larger than the last-
byte-pos returned in response to an open-ended byte-range HEAD byte-pos returned in response to an open-ended byte-range HEAD
request, as described above. request, as described above.
In response, a server may indicate that it is supplying a In response, a server may indicate that it is supplying a
continuously aggregating ("live") response by supplying the client continuously aggregating ("live") response by supplying the client
request's last-byte-pos in the Content-Range response header. request's last-byte-pos in the Content-Range response header.
For example: For example:
GET /resource HTTP/1.1 GET /resource HTTP/1.1
Host: example.com
Range: bytes=1230000-999999999999 Range: bytes=1230000-999999999999
returns returns
HTTP/1.1 206 Partial Content HTTP/1.1 206 Partial Content
Content-Range: bytes 1230000-999999999999/* Content-Range: bytes 1230000-999999999999/*
from the server to indicate that the response will start at byte from the server to indicate that the response will start at byte
1230000 and continues indefinitely to include all aggregated content, 1230000 and continues indefinitely to include all aggregated content,
as it becomes available. as it becomes available.
A server that doesn't support or supply a continuously aggregating A server that doesn't support or supply a continuously aggregating
("live") response will supply the currently satisfiable byte range, ("live") response will supply the currently satisfiable byte range,
as it would with an open-ended byte request. as it would with an open-ended byte request.
For example: For example:
GET /resource HTTP/1.1 GET /resource HTTP/1.1
Host: example.com
Range: bytes=1230000-999999999999 Range: bytes=1230000-999999999999
will return will return
HTTP/1.1 206 Partial Content HTTP/1.1 206 Partial Content
Content-Range: bytes 1230000-1234567/* Content-Range: bytes 1230000-1234567/*
from the server to indicate that the response will start at byte from the server to indicate that the response will start at byte
1230000 and end at byte 1234567 and will not include any aggregated 1230000 and end at byte 1234567 and will not include any aggregated
content. This is the response expected from a typical HTTP server - content. This is the response expected from a typical HTTP server -
one that doesn't support byte-range requests on aggregating content. one that doesn't support byte-range requests on aggregating content.
A client that doesn't receive a response indicating it is A client that doesn't receive a response indicating it is
continuously aggregating must use other means to access aggregated continuously aggregating must use other means to access aggregated
content (e.g. periodic byte-range polling). content (e.g. periodic byte-range polling).
A server that does return a continuously aggregating ("live") A server that does return a continuously aggregating ("live")
response should return data using chunked transfer coding and not response should return data using chunked transfer coding and not
provide a Content-Length header. A 0-length chunk indicates the end provide a Content-Length header. A 0-length chunk indicates the end
of the transfer, per section 4.1 of [RFC7230]. of the transfer, per Section 4.1 of [RFC7230].
3. Other Applications of Random-Access Aggregating Content 3. Other Applications of Random-Access Aggregating Content
3.1. Requests Starting at the Aggregation ("Live") Point 3.1. Requests Starting at the Aggregation ("Live") Point
A client that wishes to only receive newly-aggregated portions of a A client that wishes to only receive newly-aggregated portions of a
resource (i.e., start at the "live" point), can use a HEAD request to resource (i.e., start at the "live" point), can use a HEAD request to
learn what range the server has currently available and initiate an learn what range the server has currently available and initiate an
indeterminate-length transfer. For example: indeterminate-length transfer. For example:
HEAD /resource HTTP/1.1 HEAD /resource HTTP/1.1
Host: example.com
Range: bytes=0- Range: bytes=0-
With the Content-Range response header indicating the (or ranges) With the Content-Range response header indicating the (or ranges)
available. For example: available. For example:
206 Partial Content 206 Partial Content
Content-Range: bytes 0-1234567/* Content-Range: bytes 0-1234567/*
The client can then issue a request for a range starting at the end The client can then issue a request for a range starting at the end
value (using a very large value for the end of a range) and receive value (using a very large value for the end of a range) and receive
only new content. only new content.
GET /resource HTTP/1.1 GET /resource HTTP/1.1
Host: example.com
Range: bytes=1234567-999999999999 Range: bytes=1234567-999999999999
with a server returning a Content-Range response indicating that an with a server returning a Content-Range response indicating that an
indeterminate-length response body will be provided indeterminate-length response body will be provided
206 Partial Content 206 Partial Content
Content-Range: bytes 1234567-999999999999/* Content-Range: bytes 1234567-999999999999/*
3.2. Shift Buffer Representations 3.2. Shift Buffer Representations
Some representations lend themselves to front-end content deletion in Some representations lend themselves to front-end content deletion in
addition to aggregation. While still supporting random access, addition to aggregation. While still supporting random access,
representations of this type have a portion at the beginning (the "0" representations of this type have a portion at the beginning (the "0"
end) of the randomly-accessible region that become inaccessible over end) of the randomly-accessible region that become inaccessible over
time. Examples of this kind of representation would be an audio- time. Examples of this kind of representation would be an audio-
video time-shift buffer or a rolling log file. video time-shift buffer or a rolling log file.
For example a Range request containing: For example a Range request containing:
HEAD /resource HTTP/1.1 HEAD /resource HTTP/1.1
Host: example.com
Range: bytes=0- Range: bytes=0-
returns returns
206 Partial Content 206 Partial Content
Content-Range: bytes 1000000-1234567/* Content-Range: bytes 1000000-1234567/*
indicating that the first 1000000 bytes were not accessible at the indicating that the first 1000000 bytes were not accessible at the
time the HEAD request was processed. Subsequent HEAD requests could time the HEAD request was processed. Subsequent HEAD requests could
return: return:
Content-Range: bytes 1000000-1234567/* Content-Range: bytes 1000000-1234567/*
Content-Range: bytes 1010000-1244567/* Content-Range: bytes 1010000-1244567/*
Content-Range: bytes 1020000-1254567/* Content-Range: bytes 1020000-1254567/*
Note though that the difference between the first-byte-pos and last- Note though that the difference between the first-byte-pos and last-
byte-pos need not be constant. byte-pos need not be constant.
The client could then follow-up with a GET Range request containing The client could then follow-up with a GET Range request containing
GET /resource HTTP/1.1 GET /resource HTTP/1.1
Host: example.com
Range: bytes=1020000-999999999999 Range: bytes=1020000-999999999999
with the server returning with the server returning
206 Partial Content 206 Partial Content
Content-Range: bytes 1020000-999999999999/* Content-Range: bytes 1020000-999999999999/*
with the response body returning bytes 1020000-1254567 immediately with the response body returning bytes 1020000-1254567 immediately
and aggregated ("live") data being returned as the content is and aggregated ("live") data being returned as the content is
aggregated. aggregated.
A server that doesn't support or supply a continuously aggregating
("live") response will supply the currently satisfiable byte range,
as it would with an open-ended byte request.
For example:
GET /resource HTTP/1.1
Host: example.com
Range: bytes=0-999999999999
will return
HTTP/1.1 206 Partial Content
Content-Range: bytes 1020000-1254567/*
from the server to indicate that the response will start at byte
1020000, end at byte 1254567, and will not include any aggregated
content. This is the response expected from a typical HTTP server -
one that doesn't support byte-range requests on aggregating content.
4. Security Considerations 4. Security Considerations
One potential issue with this recommendation is related to the use of One potential issue with this recommendation is related to the use of
very-large last-byte-pos values. Some client and server very-large last-byte-pos values. Some client and server
implementations may not be prepared to deal with byte position values implementations may not be prepared to deal with byte position values
of 2^^63 and beyond. So in applications where there's no expectation of 2^^63 and beyond. So in applications where there's no expectation
that the representation will ever exceed 2^^63, a value smaller than that the representation will ever exceed 2^^63, a value smaller than
this value should be used as the Very Large last-byte-pos in a byte- this value should be used as the Very Large last-byte-pos in a byte-
seek request or content-range response. Also, some implementations seek request or content-range response. Also, some implementations
(e.g. JavaScript-based clients and servers) are not able to (e.g. JavaScript-based clients and servers) are not able to
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RFC 7230, DOI 10.17487/RFC7230, June 2014, RFC 7230, DOI 10.17487/RFC7230, June 2014,
<https://www.rfc-editor.org/info/rfc7230>. <https://www.rfc-editor.org/info/rfc7230>.
[RFC7233] Fielding, R., Ed., Lafon, Y., Ed., and J. Reschke, Ed., [RFC7233] Fielding, R., Ed., Lafon, Y., Ed., and J. Reschke, Ed.,
"Hypertext Transfer Protocol (HTTP/1.1): Range Requests", "Hypertext Transfer Protocol (HTTP/1.1): Range Requests",
RFC 7233, DOI 10.17487/RFC7233, June 2014, RFC 7233, DOI 10.17487/RFC7233, June 2014,
<https://www.rfc-editor.org/info/rfc7233>. <https://www.rfc-editor.org/info/rfc7233>.
5.2. Informative References 5.2. Informative References
[RANGE-UNIT-REGISTRY] [DASH] ISO, "Information technology -- Dynamic adaptive streaming
IANA, "Hypertext Transfer Protocol (HTTP) Parameters", over HTTP (DASH) -- Part 1: Media presentation description
2016, <http://www.iana.org/assignments/http-parameters/ and segment formats", ISO/IEC 23009-1:2014, May 2014,
http-parameters.xhtml#range-units>. <http://standards.iso.org/ittf/PubliclyAvailableStandards/
c065274_ISO_IEC_23009-1_2014.zip>.
[RFC4234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax [RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 4234, DOI 10.17487/RFC4234, Specifications: ABNF", STD 68, RFC 5234,
October 2005, <https://www.rfc-editor.org/info/rfc4234>. DOI 10.17487/RFC5234, January 2008,
<https://www.rfc-editor.org/info/rfc5234>.
Appendix A. Acknowledgements [RFC8216] Pantos, R., Ed. and W. May, "HTTP Live Streaming",
RFC 8216, DOI 10.17487/RFC8216, August 2017,
<https://www.rfc-editor.org/info/rfc8216>.
Acknowledgements
Mark Nottingham, Patrick McManus, Julian Reschke, Remy Lebeau, Rodger Mark Nottingham, Patrick McManus, Julian Reschke, Remy Lebeau, Rodger
Combs, Thorsten Lohmar, Martin Thompson, Adrien de Croy, K. Morgan, Combs, Thorsten Lohmar, Martin Thompson, Adrien de Croy, K. Morgan,
Roy T. Fielding, Jeremy Poulter. Roy T. Fielding, Jeremy Poulter.
Authors' Addresses Authors' Addresses
Craig Pratt Craig Pratt
CableLabs Portland, OR 97229
858 Coal Creek Circle US
Louisville, CO 80027
Email: pratt@acm.org Email: pratt@acm.org
Barbara Stark Barbara Stark
AT&T AT&T
Atlanta, GA Atlanta, GA
US US
Email: barbara.stark@att.com Email: barbara.stark@att.com
Darshak Thakore Darshak Thakore
CableLabs CableLabs
858 Coal Creek Circle 858 Coal Creek Circle
Louisville, CO 80027 Louisville, CO 80027
Email: d.thakore@cablelabs.com Email: d.thakore@cablelabs.com
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