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ABNF Notation
Session Description
Addressing
generic rules
"a=" SDP Attributes
SDP attributes defined in
RFC 4585 – RTCP-based Feedback
RFC 4585
–
Section 4.2
—
Errata ID: 2853
–
Errata ID: 3313
— see also:
IANA
a=
rtcp-fb
attribute-fields
=/
rtcp-fb-syntax
rtcp-fb-syntax
=
"
a=rtcp-fb:
"
rtcp-fb-pt
SP
rtcp-fb-val
CRLF
rtcp-fb-pt
=
"
*
" /
fmt
; wildcard: applies to all formats
rtcp-fb-val
=
"
ack
"
rtcp-fb-ack-param
/
"
nack
"
rtcp-fb-nack-param
/
"
trr-int
"
SP
1*
DIGIT
/
rtcp-fb-id
rtcp-fb-param
/
"
ccm
"
rtcp-fb-ccm-param
; see
RFC 5104
–
Section 7.1
rtcp-fb-id
=
1*(
alpha-numeric
/ "
-
" / "
_
" )
rtcp-fb-param
=
[
SP
"
app
" [
SP
byte-string
] /
SP
token
[
SP
byte-string
]
]
rtcp-fb-ack-param
=
SP
"
rpsi
" /
SP
"
app
" [
SP
byte-string
] /
SP
token
[
SP
byte-string
]
rtcp-fb-nack-param
=
[
SP
"
pli
" /
SP
"
sli
" /
SP
"
rpsi
" /
SP
"
app
" [
SP
byte-string
] /
SP
"
tllei
" /
; see
RFC 6642
–
Section 8
SP
"
pslei
" /
; see RFC 6642
SP
"
rai
" /
; see
RFC 6285
–
Section 8
SP
"
ecn
" /
; see
RFC 6679
–
Section 10.3
SP
token
[
SP
byte-string
]
]
rtcp-fb-ccm-param
=
SP
"
fir
" /
; Full Intra Request
SP "
tmmbr
"
; Temporary max media bit rate
[
SP
"
smaxpr=
"
MaxPacketRateValue
] /
SP
"
tstr
" /
; Temporal-Spatial Trade-Off
SP
"
vbcm
" *( SP
subMessageType
) /
; H.271 VBCMs
SP
token
[
SP
byte-string
]
; for future commands/indications
MaxPacketRateValue
=
1*15
DIGIT
subMessageType
=
1*8
DIGIT