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SDP
Generic URI
ABNF Notation
Session Description
Addressing
generic rules
"a=" SDP Attributes
SDP attributes defined in
RFC 3312 – Preconditions for session establishment
RFC 3312
–
Section 4
a=
curr
a=
des
a=
conf
attribute-fields
=/
current‑status
/
desired‑status
/
confirm‑status
current-status
=
"
a=curr:
"
precondition‑type
SP
status‑type
SP
direction‑tag
CRLF
desired-status
=
"
a=des:
"
precondition‑type
SP
strength‑tag
SP
status‑type
SP
direction‑tag
CRLF
confirm-status
=
"
a=conf:
"
precondition‑type
SP
status‑type
SP
direction‑tag
CRLF
precondition-type
=
"
qos
" /
; Quality of Service
RFC 3312
–
Section 4
"
sec
" /
; Security
RFC 5027
–
Section 3
"
conn
" /
; Connectivity
RFC 5898
–
Section 3
token
; see
IANA
strength-tag
=
( "
mandatory
" / "
optional
" / "
none
" / "
failure
" / "
unknown
" )
status-type
=
( "
e2e
" / "
local
" / "
remote
" )
direction-tag
=
( "
none
" / "
send
" / "
recv
" / "
sendrecv
" )