back to RFC 3261  

ABNF for SIP: from RFC 3261 and other RFCs

Verification with IANA is in progress
SIP-message =
Request /  Response
Request =
Request-Line  *( message-header )  CRLF  [ message-body ]
; Here is an example:
Response =
Status-Line  *(  message-header )  CRLF  [ message-body ]
; Here is an example:
Request-Line =
Method  SP  Request-URI  SP  SIP-Version  CRLF
Status-Line =
SIP-Version  SP  Status-Code  SP  Reason-Phrase  CRLF
Method =
INVITEm /  ACKm /  OPTIONSm /  BYEm /  CANCELm /  REGISTERm /  INFOm /  PRACKm /  SUBSCRIBEm /  NOTIFYm /  UPDATEm /  MESSAGEm /  REFERm /  PUBLISHm /  extension-method
Request-URI =
SIP‑URI /  SIPS‑URI /  absoluteURI
SIP-Version =
"SIP"   "/"   1*DIGIT  "."   1*DIGIT
Reason-Phrase =
*( reserved /  unreserved /  escaped /  UTF8‑NONASCII /  UTF8‑CONT /  SP /  HTAB )
message-header =
( Accept /  Accept‑Contact /  Accept‑Encoding /  Accept‑Language /  Accept‑Resource‑Priority /  Additional‑Identity /  Alert‑Info /  AlertMsg‑Error /  Allow /  Allow‑Events /  Answer‑Mode /  Attestation‑Info /  Authentication‑Info /  Authorization /  Call‑ID /  Call‑Info /  Cellular‑Network‑Info /  Contact /  Content‑Disposition /  Content‑Encoding /  Content‑ID /  Content‑Language /  Content‑Length /  Content‑Type /  CSeq /  Date /  Error‑Info /  Event /  Expires /  Feature‑Caps /  Flow‑Timer /  From /  Geolocation /  Geolocation‑Error /  Geolocation‑Routing /  History‑Info /  Identity /  Identity‑Info /  Info‑Package /  In‑Reply‑To /  Join /  Max‑Breadth /  Max‑Forwards /  MIME‑Version /  Min‑Expires /  Min‑SE /  Organization /  Origination‑Id /  P‑Access‑Network‑Info /  P‑Answer‑State /  P‑Asserted‑Identity /  P‑Asserted‑Service /  P‑Associated‑URI /  P‑Called‑Party‑ID /  P‑Charge‑Info /  P‑Charging‑Function‑Addresses /  P‑Charging‑Vector /  P‑DCS‑Billing‑Info /  P‑DCS‑LAES /  P‑DCS‑OSPS /  P‑DCS‑Redirect /  P‑DCS‑Trace‑Party‑ID /  P‑Early‑Media /  P‑Media‑Authorization /  P‑Preferred‑Identity /  P‑Preferred‑Service /  P‑Private‑Network‑Indication /  P‑Profile‑Key /  P‑Refused‑URI‑List /  P‑Served‑User /  P‑User‑Database /  P‑Visited‑Network‑ID /  Path /  Permission‑Missing /  Policy‑Contact /  Policy‑ID /  Priority /  Priority‑Share /  Priority‑Verstat /  Privacy /  Priv‑Answer‑Mode /  Proxy‑Authenticate /  Proxy‑Authorization /  Proxy‑Require /  RAck /  Reason /  Record‑Route /  Recv‑Info /  Refer‑Events‑At /  Refer‑Sub /  Refer‑To /  Referred‑By /  Reject‑Contact /  Relayed‑Charge /  Replaces /  Reply‑To /  Request‑Disposition /  Require /  Resource‑Priority /  Resource‑Share /  Response‑Source /  Restoration‑Info /  Retry‑After /  Route /  RSeq /  Security‑Client /  Security‑Server /  Security‑Verify /  Server /  Service‑Interact‑Info /  Service‑Route /  Session‑Expires /  Session‑ID /  SIP‑ETag /  SIP‑If‑Match /  Subject /  Subscription‑State /  Supported /  Suppress‑If‑Match /  Target‑Dialog /  Timestamp /  To /  Trigger‑Consent /  Unsupported /  User‑Agent /  User‑to‑User /  Via /  Warning /  WWW‑Authenticate /  extension‑header )  CRLF
message-body =
*OCTET
extension-header =
header‑name   HCOLON   header‑value
header-name =
token
header-value =
*( TEXT‑UTF8char /  UTF8‑CONT /  LWS )
extension-method =
token
INVITEm =
%x49.4E.56.49.54.45
; INVITE in caps  
;  RFC 6026 – Section 9
ACKm =
%x41.43.4B
; ACK in caps  
OPTIONSm =
%x4F.50.54.49.4F.4E.53
; OPTIONS in caps
BYEm =
%x42.59.45
; BYE in caps
CANCELm =
%x43.41.4E.43.45.4C
; CANCEL in caps
REGISTERm =
%x52.45.47.49.53.54.45.52
; REGISTER in caps
INFOm =
%x49.4E.46.4F
; INFO in caps
;  RFC 6086 – Section 11.1
PRACKm =
%x50.52.41.43.4B
; PRACK in caps
;  RFC 3262 – Section 6
SUBSCRIBEm =
%x53.55.42.53.43.52.49.42.45
; SUBSCRIBE in caps
;  RFC 6665 – Section 8.1.1
NOTIFYm =
%x4E.4F.54.49.46.59
; NOTIFY in caps
;  RFC 6665 – Section 8.1.2
UPDATEm =
%x55.50.44.41.54.45
; UPDATE in caps
;  RFC 3311 – Section 10
MESSAGEm =
%x4D.45.53.53.41.47.45
; MESSAGE in caps
;  RFC 3428 – Section 12
REFERm =
%x52.45.46.45.52
; REFER in caps
;  RFC 3515 – Section 7
PUBLISHm =
%x50.55.42.4C.49.53.48
; PUBLISH in caps
;  RFC 3903 – Section 13.1
Top
Accept =
"Accept"  HCOLON  [ accept‑range  *( COMMA  accept‑range ) ]
accept-range =
media‑range  *( SEMI  accept‑param )
media-range =
( "*/*" /  ( m‑type  SLASH  "*" ) / 
( m‑type  SLASH  m‑subtype ) )  *( SEMI  m‑parameter )
Up
Accept-Contact =
( "Accept‑Contact" /  "a" )  HCOLON  ac‑value  *( COMMA  ac‑value )

; examples:
; Accept‑Contact: *;audio;require
; Accept‑Contact: *;video;explicit
; Accept‑Contact: *;methods="BYE";class="business";q=1.0

ac-value =
"*"  *( SEMI  ac‑params )
ac-params =
feature‑param /  req‑param /  explicit‑param /  generic‑param
req-param =
"require"
explicit-param =
"explicit"
Up
Accept-Encoding =
"Accept‑Encoding"  HCOLON  [ encoding  *( COMMA  encoding ) ]

; example:
; Accept‑Encoding: gzip

encoding =
codings  *( SEMI  accept‑param )
codings =
content‑coding /  "*"
Up
Accept-Language =
"Accept-Language"  HCOLON  [ language  *( COMMA  language ) ]

; example:
; Accept-Language: da, en-gb;q=0.8, en;q=0.7

language =
language‑range  *( SEMI  accept‑param )
language-range =
(  ( 1*8ALPHA  *( "-"  1*8ALPHA ) ) /  "*" )
Up
Accept-Resource-Priority =
"Accept‑Resource‑Priority"  HCOLON  [ r‑value  *( COMMA  r‑value ) ]

; example:
; Accept‑Resource‑Priority: dsn.flash‑override,
;  dsn.flash, dsn.immediate, dsn.priority, dsn.routine

Up
Alert-Info =
"Alert-Info"  HCOLON  alert‑param  *( COMMA  alert‑param )

; example:
; Alert‑Info: <http://www.example.com/sounds/moo.wav>

alert-param =
LAQUOT  absoluteURI  RAQUOT  *( SEMI  ( generic‑param /  appearance‑param ) )
appearance-param =
"appearance"  EQUAL  1*DIGIT
Up
Allow =
"Allow"  HCOLON  [ Method  *( COMMA  Method ) ]

; example:
; Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, NOTIFY

Up
Allow-Events =
( "Allow‑Events" /  "u" )  HCOLON  event‑type  *( COMMA  event‑type )

; example:
; Allow‑Events: spirits‑INDPs

Up
Answer-Mode =
"Answer‑Mode"  HCOLON  answer‑mode‑value  *( SEMI  answer‑mode‑param )

; example:
; Answer‑Mode: Manual

answer-mode-value =
"Manual" /  "Auto" /  token
answer‑mode‑param =
"require" /  generic‑param
Up
Attestation-Info =
"Attestation‑Info"  HCOLON  attestation‑level /  generic‑param
attestation‑level =
( "A" /  "B" /  "C"
Up
Authentication-Info =
"Authentication-Info"  HCOLON  ainfo  *( COMMA  ainfo )

; example:
; Authentication-Info: nextnonce="47364c23432d2e131a5fb210812c"

ainfo =
nextnonce /  message‑qop /  response‑auth /  cnonce /  nonce‑count
nextnonce =
"nextnonce"  EQUAL  nonce‑value
response-auth =
"rspauth"  EQUAL  response‑digest
response-digest =
LDQUOT  *LHEX  RDQUOT
Up
Authorization =
"Authorization"  HCOLON  credentials

; example:
; Authorization: Digest username="bob", realm="atlanta.example.com"
;  nonce="ea9c8e88df84f1cec4341ae6cbe5a359", opaque="",
;  uri="sips:ss2.biloxi.example.com",
;  response="dfe56131d1958046689d83306477ecc"

credentials =
( "Digest"  LWS  digest‑response ) /  other‑response
digest-response =
dig‑resp  *( COMMA  dig‑resp )
dig-resp =
username /
realm /
nonce /
digest‑uri /
dresponse /
algorithm /   ; see  RFC 3310 – Section 3.1
cnonce /
opaque /
message‑qop /
nonce‑count /
auth‑param /   ; see  3GPP TS 24.229 – Section 7.2A.2
auts   ; see  RFC 3310 – Section 3.4
username =
"username"  EQUAL  username‑value
username-value =
quoted‑string
digest-uri =
"uri"  EQUAL  LDQUOT  digest‑uri‑value  RDQUOT
digest-uri-value =
request-uri   ; equal to request-uri as specified by HTTP/1.1
message-qop =
"qop"  EQUAL  qop‑value
cnonce =
"cnonce"  EQUAL  cnonce‑value
cnonce-value =
nonce‑value
nonce-count =
"nc"  EQUAL  nc‑value
nc-value =
8LHEX
dresponse =
"response"  EQUAL  request‑digest
request-digest =
LDQUOT  32LHEX  RDQUOT
auth-param =
auth‑param‑name  EQUAL  ( token /  quoted‑string )
auth-param =   ; as redefined by 3GPP TS 24.229
"integrity-protected"  EQUAL 
( "yes" /  "no" /  "tls‑pending" /  "tls‑yes" /  "ip‑assoc‑pending" /  "ip‑assoc‑yes" /  "auth‑done" )
auth-param-name =
token
auts =
"auts"  EQUAL  auts‑param
auts-param =
LDQUOT  auts‑value  RDQUOT
auts-value =
<base64 encoding of AUTS>
other-response =
auth‑scheme  LWS  auth‑param  *( COMMA  auth‑param )
auth-scheme =
token
Up
Call-ID =
( "Call-ID" /  "i" )  HCOLON  callid

; example:
; Call-ID: 3848276298220188511@atlanta.example.com

Up
Call-Info =
"Call-Info"  HCOLON  info  *( COMMA  info )

; examples:
; Call-Info: <http://www.example.com/alice/photo.jpg> ;purpose=icon,
;  <http://www.example.com/alice/> ;purpose=info
; Call-Info:<sip:456@z.b.com>;purpose=call‑completion;m=NR

info =
LAQUOT  absoluteURI  RAQUOT  *( SEMI  info‑param )
info-param =
( "purpose"  EQUAL  (
"icon" /  "info" /  "card" /
"list‑management" /  ; see  RFC 5367 – Section 9
"call‑completion" /  ; see  RFC 6910 – Section 12.4
"impp" /  ; see  RFC 6993 – Section 3
"ccmp" /  ; see  RFC 7082 – Section 5.1
"EmergencyCallData" /  ; see  RFC 7852 – Section 11.2
token )
/  ( "m"  EQUAL  ( "BS" /  "NR" /  "NL" ) )     ; see  RFC 6910 – Section 12.5
/  generic‑param
Up
Cellular-Network-Info =
"Cellular‑Network‑Info"  HCOLON  cellular‑net‑spec
cellular-net-spec =
access‑type  *( SEMI  cellular‑access‑info )
access-type =
"3GPP‑GERAN" /  "3GPP‑UTRAN‑FDD" /  "3GPP‑UTRAN‑TDD" /  "3GPP‑E‑UTRAN‑FDD" /  "3GPP‑E‑UTRAN‑TDD" /  "3GPP2‑1X‑Femto" /  "3GPP2‑UMB" /  "3GPP2‑1X‑HRPD" /  "3GPP2‑1X" /  "3GPP‑E‑UTRAN‑ProSe‑UNR" /  token
cellular-access-info =
access‑info /  cell‑info‑age
access-info =
cgi‑3gpp /  utran‑cell‑id‑3gpp /  ci‑3gpp2 /  ci‑3gpp2‑femto /  extension‑access‑info
cgi-3gpp =
"cgi-3gpp"  EQUAL  ( token /  quoted‑string )
utran-cell-id-3gpp =
"utran-cell-id-3gpp"  EQUAL  ( token /  quoted‑string )
ci-3gpp2 =
"ci-3gpp2"  EQUAL  ( token /  quoted‑string )
ci-3gpp2-femto =
"ci-3gpp2-femto"  EQUAL  ( token /  quoted‑string )
cell-info-age =
"cell-info-age"  EQUAL  1*9DIGIT
extension-access-info =
generic‑param
Up
Contact =
( "Contact" /  "m" )  HCOLON  ( STAR /  ( contact‑param  *( COMMA  contact‑param ) ) )
contact-param =
( name‑addr /  addr‑spec )  *( SEMI  contact‑params )
contact-params =
c‑p‑q /  c‑p‑expires /  ; see  RFC 3261
feature‑param /  ; see  RFC 3840 – Section 9
c‑p‑reg /  c‑p‑instance /  ; see  RFC 5626 – Section 10
temp‑gruu /  pub‑gruu /  ; see  RFC 5627 – Section 7
temp‑gruu‑cookie /  ; see  RFC 6140 – Section 9.3
mp‑param /  rc‑param /  np‑param /  ; see  RFC 7044 – Section 14.3
contact‑extension
c-p-q =
"q"  EQUAL  qvalue
c-p-expires =
"expires"  EQUAL  delta‑seconds
feature-param =
enc‑feature‑tag  [ EQUAL  LDQUOT  ( tag‑value‑list /  string‑value )  RDQUOT ]
enc-feature-tag =
base‑tags /  other‑tags
base-tags =
"audio" /  "automata" /  "class" /  "duplex" /  "data" /  "control" /  "mobility" /  "description" /  "events" /  "priority" /  "methods" /  "schemes" /  "application" /  "video" /  "language" /  "type" /  "isfocus" /  "actor" /  "text" /  "extensions"
other-tags =
"+"  ftag‑name
ftag-name =
ALPHA  *( ALPHA /  DIGIT /  "!" /  "'" /  "." /  "-" /  "%" )
tag-value-list =
tag‑value  *( ","  tag‑value )
tag-value =
[ "!" ]  ( token‑nobang /  boolean /  numeric )
token-nobang =
1*( alphanum /  "-" /  "." /  "%" /  "*" /  "_" /  "+" /  "`" /  "'" /  "~" )
boolean =
"TRUE" /  "FALSE"
numeric =
"#"  numeric‑relation  number
numeric-relation =
">=" /  "<=" /  "=" /  ( number  ":" )
number =
[ "+" /  "-" ]  1*DIGIT  [ "."  0*DIGIT ]
string-value =
"<"  *( qdtext‑no‑abkt /  quoted‑pair )  ">"
qdtext-no-abkt =
LWS /  %x21 /  %x23‑3B /  %x3D /  %x3F‑5B /  %x5D‑7E /  UTF8‑NONASCII
c-p-reg =
"reg-id"  EQUAL  1*DIGIT
;  1 to (2^31 - 1)
c-p-instance =
"+sip.instance"  EQUAL  LDQUOT  "<"  instance-val  ">"  RDQUOT
instance-val =
*uric
temp-gruu =
"temp-gruu"  EQUAL  LDQUOT  *( qdtext /  quoted‑pair )  RDQUOT
pub-gruu =
"pub‑gruu"  EQUAL  LDQUOT  *( qdtext /  quoted‑pair )  RDQUOT
contact-extension =
generic‑param
Up
Content-Disposition =
"Content‑Disposition"  HCOLON  disp‑type  *( SEMI  disp‑param )

; example:
; Content-Disposition: session;handling=optional

disp-type =
"render" /  "session" /  "icon" /  "alert" /  ; see  RFC 3261
"aib" /  ; see  RFC 3893 – Section 2
"early-session" /  ; see  RFC 3959 – Section 4
"by-reference" /  ; see  RFC 5621 – Section 9.4
disp‑extension‑token
disp-extension-token =
token
disp-param =
handling‑param /  generic‑param
handling-param =
"handling"  EQUAL  ( "optional" /  "required" /  other‑handling )
other-handling =
token
Up
Content-Encoding =
( "Content-Encoding" /  "e" )  HCOLON  content‑coding  *( COMMA  content‑coding )

; example:
; Content‑Encoding: gzip

content-coding =
token
; see  IANA
Up
Content-ID =
"Content-ID"  HCOLON  msg‑id

; example:
; Content‑ID: <cn35t8jf02@example.com>

msg-id =
"<"  id-left  "@"  id-right  ">"
Up
Content-Language =
"Content-Language"  HCOLON  language‑tag  *( COMMA  language‑tag )

; example:
; Content‑Language: fr

language-tag =
primary‑tag  *( "-"  subtag )
primary-tag =
1*8ALPHA
subtag =
1*8ALPHA
Up
Content-Length =
( "Content-Length" /  "l" )  HCOLON  1*DIGIT

; example:
; Content‑Length: 0

Up
Content-Type =
( "Content‑Type" /  "c" )  HCOLON  media‑type

; example:
; Content‑Type: application/sdp

media-type =
m‑type  SLASH  m‑subtype  *( SEMI  m‑parameter )
m-type =
discrete‑type /  composite‑type
discrete-type =
"text" /  "image" /  "audio" /  "video" /  "application" /  extension‑token
composite-type =
"message" /  "multipart" /  extension‑token
extension-token =
ietf‑token /  x‑token
ietf-token =
token
x-token =
"x-"  token
m-subtype =
extension‑token /  iana‑token
iana-token =
token
m-parameter =
m‑attribute  EQUAL  m‑value
m-attribute =
token
m-value =
token /  quoted‑string
Up
CSeq =
"CSeq"  HCOLON  1*DIGIT  LWS  Method

; example:
; CSeq: 1 INVITE

Up
Date =
"Date"  HCOLON  SIP-date

; example:
; Date: Thu, 21 Feb 2002 13:02:03 GMT

SIP-date =
rfc1123-date
rfc1123-date =
wkday  ","  SP  date1  SP  time  SP  "GMT"
wkday =
"Mon" /  "Tue" /  "Wed" /  "Thu" /  "Fri" /  "Sat" /  "Sun"
date1 =
2DIGIT  SP  month  SP  4DIGIT
;  day month year (e.g., 02 Jun 1982)
month =
"Jan" /  "Feb" /  "Mar" /  "Apr" /  "May" /  "Jun" /  "Jul" /  "Aug" /  "Oct" /  "Nov" /  "Dec"
time =
2DIGIT  ":"  2DIGIT  ":"  2DIGIT
;  e.g., 00:00:00 - 23:59:59
Up
Error-Info =
"Error-Info"  HCOLON  error‑uri  *( COMMA  error‑uri )

; example:
; Error-Info: <sips:screen-failure-term-ann@annoucement.example.com>

error-uri =
LAQUOT  absoluteURI  RAQUOT  *( SEMI  generic‑param )
Up
Event =
( "Event" /  "o" )  HCOLON  event‑type  *( SEMI  event‑param )

; example:
; Event: refer

event-type =
event‑package  *( "."  event‑template )

; refer  RFC 3515 – Section 3
; reg  RFC 3680 – Section 4
; message-summary  RFC 3842 – Section 3
; presence  RFC 3856 – Section 6
; winfo   (template)  RFC 3857 – Section 4
; spirits-INDPs  RFC 3910 – Section 5.3.2
; spirits-user-prof  RFC 3910 – Section 6.3
; dialog  RFC 4235 – Section 3
; poc-settings  RFC 4354 – Section 5
; conference  RFC 4575 – Section 3
; kpml  RFC 4730 – Section 4
; consent-pending-additions  RFC 5362 – Section 5
; xcap-diff  RFC 5875 – Section 4
; http-monitor  RFC 5989 – Section 4
; vq-rtcpxr  RFC 6035 – Section 4
; certificate  RFC 6072 – Section 6
; credential  RFC 6072 – Section 7
; ua-profile  RFC 6080 – Section 6
; session-spec-policy  RFC 6795 – Section 3
; call-completion  RFC 6910 – Section 9
; load-control  RFC 7200 – Section 4

event-package =
token‑nodot
event-template =
token‑nodot
token-nodot =
1*( alphanum  /  "-"  /  "!"  /  "%"  /  "*"  /  "_"  /  "+"  /  "`"  /  "'"  /  "~" )
event-param =
generic‑param /  ( "id"  EQUAL  token ) /  ; see  RFC 6665 – Section 8.4
call‑ident /  from‑tag /  to‑tag /  with‑sessd /  ; see  RFC 4235 – Section 3.2
body‑event‑param /  ; see  RFC 5989 – Section 4.2
Profile‑type /  Vendor /  Model /  Version /  Effective‑By /  ; see  RFC 6080 – Sections 6.2.1 – 6.2.2 – 6.2.3
max‑rate‑param /  min‑rate‑param /  amin‑rate‑param /  ; see  RFC 6446 – Section 9.2
"shared"  ; see  RFC 7463 – Section 13.1
call-ident =
"call‑id"  EQUAL  ( token /  DQUOTE  callid  DQUOTE )
with-sessd =
"include‑session‑description"
body-event-param =
"body"  EQUAL  ( "true" /  "false" )
Profile-type =
"profile-type"  EQUAL  profile‑value
profile-value =
profile‑types /  token
profile-types =
"device" /  "user" /  "local‑network"
Vendor =
"vendor"  EQUAL  quoted‑string
Model =
"model"  EQUAL  quoted‑string
Version =
"version"  EQUAL  quoted‑string
Effective-By =
"effective-by"  EQUAL  1DIGIT
max-rate-param =
"max‑rate"  EQUAL  ( 1*2DIGIT  [ "."  1*10DIGIT ] )
min-rate-param =
"min‑rate"  EQUAL  ( 1*2DIGIT  [ "."  1*10DIGIT ] )
amin-rate-param =
"adaptive-min-rate"  EQUAL  ( 1*2DIGIT  [ "."  1*10DIGIT ] )
Up
Expires =
"Expires"  HCOLON  delta‑seconds

; example:
; Expires: 7200

Up
Feature-Caps =
"Feature-Caps"  HCOLON  fc‑value  *( COMMA  fc‑value )
fc-value =
"*"  *( SEMI  feature‑cap )
feature-cap =
"+"  fcap‑name  [ EQUAL  LDQUOT  ( fcap‑value‑list  /  fcap‑string‑value )  RDQUOT ]
fcap-name =
ftag‑name
fcap-value-list =
tag‑value‑list
fcap-string-value =
string‑value
Up
Flow-Timer =
"Flow-Timer"  HCOLON  1*DIGIT

; example:
; Flow‑Timer: 120

Up
From =
( "From" /  "f" )  HCOLON  from-spec

; examples:
; From: Alice <sip:alice@atlanta.example.com>;tag=9fxced76sl
; From: "Anonymous" <sip:anonymous@anonymous.invalid>;tag=1928301774

from-spec =
( name‑addr /  addr‑spec )  *( SEMI  from‑param )
from-param =
tag‑param /  generic‑param
tag-param =
"tag"  EQUAL  token
Up
Geolocation-header =
"Geolocation"  HCOLON  locationValue  *( COMMA  locationValue )

; example:
; Geolocation: <cid:target123@atlanta.example.com>

locationValue =
LAQUOT  locationURI  RAQUOT  *( SEMI  geoloc‑param )
locationURI =
SIP‑URI /  SIPS‑URI /  absoluteURI /  ; see  RFC 3261
pres‑URI /  ; see  RFC 3859 – Appendix A
http‑URI /  https‑URI /  ; see  RFC 7230 – Sections 2.7.1 – 2.7.2
cid-url  ; not defined here: see  RFC 2392 – Section 2
pres-URI =
"pres:"  [ to ]  [ headers ]
to =
mailbox
headers =
"?"  header  *( "&"  header )
header =
hname  "="  hvalue
hname =
*uric
hvalue =
*uric
geoloc-param =
generic‑param
Up
Geolocation-Error =
"Geolocation-Error"  HCOLON  locationErrorValue

; example:
; Geolocation-Error: 100 ; code="Cannot Process Location"

locationErrorValue =
location-error-code  *( SEMI  location-error-params )
location-error-code =
1*3DIGIT
location-error-params =
location-error-code-text /  generic‑param
location-error-code-text =
"code"  EQUAL  quoted‑string
; 100   "Cannot Process Location"
; 200   "Permission To Use Location Information"
; 201   "Permission To Retransmit Location Information to a Third Party"
; 202   "Permission to Route based on Location Information"
; 300   "Dereference Failure"
Up
Georouting-header =
"Geolocation-Routing"  HCOLON  ( "yes" /  "no" /  generic‑value )

; example:
; Geolocation‑Routing: no

generic-value =
generic‑param
Up
History-Info =
"History‑Info"  HCOLON  hi‑entry  *( COMMA  hi‑entry )
hi-entry =
hi‑targeted‑to‑uri  *( SEMI  hi‑param )
hi-targeted-to-uri =
name‑addr
hi-param =
hi-index /  hi‑target‑param /  hi‑extension
hi-index =
"index"  EQUAL  index‑val
index-val =
number  *( "."  number )
number =
[ %x31‑39  *DIGIT ]  DIGIT
hi-target-param =
rc‑param /  mp‑param /  np‑param
rc-param =
"rc""  EQUAL  index‑val
mp-param =
"mp""  EQUAL  index‑val
np-param =
"np""  EQUAL  index‑val
hi-extension =
generic‑param
Up
Identity =
"Identity"  HCOLON  signed‑identity‑digest  SEMI  ident‑info  *( SEMI  ident‑info‑params )
signed-identity-digest =
1*( base64‑char /  "." )
ident-info =
"info"  EQUAL  ident-info-uri
ident-info-uri =
LAQUOT  absoluteURI  RAQUOT
ident-info-params =
ident‑info‑alg /  ident‑type /  ident‑info‑extension
ident-info-alg =
"alg"  EQUAL  token
ident-type =
"ppt"  EQUAL  token
ident-info-extension =
generic‑param
base64-char =
ALPHA /  DIGIT /  "/" /  "+"
Up
Up
Info-Package =
"Info‑Package"  HCOLON  Info‑package‑type

; example:
; Info‑Package: foo

Info-package-type =
Info‑package‑name  *( SEMI  Info‑package‑param )
Info-package-name =
token
Info-package-param =
generic‑param
Up
In-Reply-To =
"In-Reply-To"  HCOLON  callid  *( COMMA  callid )

; example:
; In-Reply-To: 70710@saturn.bell-tel.com, 17320@saturn.bell-tel.com

Up
Join =
"Join"  HCOLON  callid  *( SEMI  join‑param )

; example:
; Join: 12345600@atlanta.example.com;from-tag=1234567;to-tag=23431

join-param =
to‑tag /  from‑tag /  generic‑param
Up
Max-Breadth =
"Max-Breadth"  HCOLON  1*DIGIT
Up
Max-Forwards =
"Max-Forwards"  HCOLON  1*DIGIT

; example:
; Max-Forwards: 69

Up
MIME-Version =
"MIME-Version"  HCOLON  1*DIGIT  "."  1*DIGIT

; example:
; MIME-Version: 1.0

Up
Min-Expires =
"Min-Expires"  HCOLON  delta‑seconds

; example:
; Min-Expires: 60

Up
Min-SE =
"Min-SE"  HCOLON  delta‑seconds  *( SEMI  generic‑param )

; example:
; Min-SE: 3600

Up
Organization =
"Organization"  HCOLON  [ TEXT‑UTF8‑TRIM ]

; example:
; Organization: Boxes by Bob

Up
Origination-Id =
"Origination‑Id"  HCOLON  originator
originator =
UUID
Up
P-Access-Network-Info  =
"P-Access-Network-Info"  HCOLON  access-net-spec   *( COMMA  access-net-spec )
access-net-spec =
( access-type /  access-class )   *( SEMI  access-info )
access-type =
"IEEE‑802.11" /  "IEEE‑802.11a" /  "IEEE‑802.11b" /  "IEEE‑802.11g" /  "IEEE‑802.11n" /  "IEEE‑802.3" /  "IEEE‑802.3a" /  "IEEE‑802.3ab" /  "IEEE‑802.3ae" /  "IEEE‑802.3ak" /  "IEEE‑802.3ah" /  "IEEE‑802.3aq" /  "IEEE‑802.3an" /  "IEEE‑802.3e" /  "IEEE‑802.3i" /  "IEEE‑802.3j" /  "IEEE‑802.3u" /  "IEEE‑802.3y" /  "IEEE‑802.3z" /  "3GPP‑GERAN" /  "3GPP‑UTRAN‑FDD" /  "3GPP‑UTRAN‑TDD" /  "3GPP‑E‑UTRAN‑FDD" /  "3GPP‑E‑UTRAN‑TDD" /  "3GPP2‑1X‑Femto" /  "3GPP2‑UMB" /  "3GPP2‑1X‑HRPD" /  "3GPP2‑1X" /  "ADSL" /  "ADSL2" /  "ADSL2+" /  "RADSL" /  "SDSL" /  "HDSL" /  "HDSL2" /  "G.SHDSL" /  "VDSL" /  "IDSL" /  "DOCSIS" /  "GSTN" /  "GPON" /  "XGPON1" /  "DVB‑RCS2" /  token
access-class =
"3GPP‑GERAN" /  "3GPP‑UTRAN" /  "3GPP‑E‑UTRAN" /  "3GPP‑WLAN" /  "3GPP‑GAN" /  "3GPP‑HSPA" /  "3GPP2" /  token
access-info =
cgi‑3gpp /  utran‑cell‑id‑3gpp /  dsl‑location /  i‑wlan‑node‑id /  ci‑3gpp2 /  eth‑location /  ci‑3gpp2‑femto /  fiber‑location /  np /  gstn‑location /  local‑time‑zone /  dvb‑rcs2‑node‑id / 
; updated by RFC 7913:
operator‑specific‑GI /  utran‑sai‑3gpp /  extension‑access‑info
cgi-3gpp =
"cgi‑3gpp"  EQUAL  ( token /  quoted‑string )
utran-cell-id-3gpp =
"utran‑cell‑id‑3gpp"  EQUAL  ( token /  quoted‑string )
dsl-location =
"dsl‑location"  EQUAL  ( token /  quoted‑string )
i-wlan-node-id =
"i‑wlan‑node‑id"  EQUAL  ( token /  quoted‑string )
ci-3gpp2 =
"ci-3gpp2"  EQUAL  ( token /  quoted‑string )
eth-location =
"eth‑location"  EQUAL  ( token /  quoted‑string )
ci-3gpp2-femto =
"ci‑3gpp2‑femto"  EQUAL  ( token /  quoted‑string )
fiber-location =
"fiber‑location"  EQUAL  ( token /  quoted‑string )
np =
"network‑provided"
gstn-location =
"gstn‑location"  EQUAL  ( token /  quoted‑string )
local-time-zone =
"local‑time‑zone"  EQUAL  quoted‑string
dvb-rcs2-node-id =
"dvb‑rcs2‑node‑id"  EQUAL  quoted‑string
extension-access-info =
; updated by RFC 7913:
generic‑param
Up
P-Answer-State =
"P‑Answer‑State"  HCOLON  answer‑type  *( SEMI  generic‑param )
answer-type =
"Confirmed" /  "Unconfirmed" /  token
Up
PAssertedID =
"P‑Asserted‑Identity"  HCOLON  PAssertedID‑value  *( COMMA  PAssertedID‑value )

; examples:
; P‑Asserted‑Identity: "Cullen Jennings" <sip:fluffy@cisco.com>
; P‑Asserted‑Identity: tel:+14085264000

PAssertedID-value =
name‑addr  /  addr‑spec
Up
PAssertedService =
"P‑Asserted‑Service"  HCOLON  PAssertedService‑value
PAssertedService-value =
Service‑ID  *( COMMA  Service‑ID )
Service-ID =
"urn:urn‑7:"  urn‑service‑id
urn-service-id =
top‑level  *( "."  sub‑service‑id )
top-level =
let‑dig  [ *26let‑dig ]
sub-service-id =
let‑dig  [ *let‑dig ]
let-dig =
ALPHA /  DIGIT /  "-"
Up
P-Associated-URI =
"P‑Associated‑URI"  HCOLON  [ p‑aso‑uri‑spec ]  *( COMMA  p‑aso‑uri‑spec )
p-aso-uri-spec =
name‑addr  *( SEMI  ai‑param )
ai-param =
generic‑param
Up
P-Called-Party-ID =
"P‑Called‑Party‑ID"  HCOLON  called‑pty‑id‑spec

; example:
; P‑Called‑Party‑ID: sip:user1‑business@example.com

called-pty-id-spec =
name‑addr  *( SEMI  cpid‑param )
cpid-param =
generic‑param
Up
P-Charge-Info =
"P-Charge-Info"  HCOLON  ( name‑addr /  addr‑spec )

; examples:
; P-Charge-Info: <sip:+14075550134@example.net;user=phone>
; P-Charge-Info: <sip:+12345550167@example.com>
; P-Charge-Info: <sips:1234@example.com>
; P-Charge-Info: <tel:+14075551234>

Up
P-Charging-Addr =
"P-Charging-Function-Addresses"  HCOLON  charge‑addr‑params
*( COMMA  charge‑addr‑params )

; example:
; P-Charging-Function-Addresses: ccf=192.1.1.1; ccf=192.1.1.2

charge-addr-params =
charge‑addr‑param  *( SEMI  charge‑addr‑param )
charge-addr-param =
ccf /  ecf /  ccf‑2 /  ecf‑2 /  generic‑param
ccf =
"ccf"  EQUAL  gen‑value
ecf =
"ecf"  EQUAL  gen‑value
ccf-2 =
"ccf‑2"  EQUAL  gen‑value
ecf-2 =
"ecf‑2"  EQUAL  gen‑value
Up
P-Charging-Vector =
"P-Charging-Vector"  HCOLON  icid‑value  *( SEMI  charge‑params )

; example:
; P‑Charging‑Vector: icid‑value=1234bc9876e;
;    icid‑generated‑at=192.0.6.8; orig‑ioi=home1.net

charge-params =
icid‑gen‑addr /  orig‑ioi /  term‑ioi /  transit‑ioi /  related‑icid /  related‑icid‑gen‑addr /  generic‑param
icid-value =
"icid‑value"  EQUAL  gen‑value
icid-gen-addr =
"icid-generated-at"  EQUAL  host
orig-ioi =
"orig‑ioi"  EQUAL  gen‑value
term-ioi =
"term-ioi"  EQUAL  gen‑value
transit-ioi =
"transit‑ioi"  EQUAL  transit‑ioi‑list
transit-ioi-list =
DQUOTE  transit‑ioi‑param  *( COMMA  transit‑ioi‑param )  DQUOTE
transit-ioi-param =
transit‑ioi‑indexed‑value /  transit‑ioi‑void‑value
transit-ioi-indexed-value =
transit‑ioi‑name  "."  transit‑ioi‑index
transit-ioi-name =
ALPHA  *( ALPHA /  DIGIT )
transit-ioi-index =
1*DIGIT
transit-ioi-void-value =
"void"
related-icid =
"related‑icid"  EQUAL  gen‑value
related-icid-gen-addr =
"related‑icid‑generated‑at"  EQUAL  host
Up
P-DCS-Billing-Info =
"P-DCS-Billing-Info"  HCOLON  Billing‑Correlation‑ID  "/"  FEID  *( SEMI  Billing‑Info‑param )
Billing-Correlation-ID =
1*48( HEXDIG )
FEID =
1*16( HEXDIG )  "@"  host
Billing-Info-param =
RKS‑Group‑ID‑param /  Charge‑param /  Calling‑param /  Called‑param /  Routing‑param /  Loc‑Routing‑param /  JIP‑param /  generic‑param
RKS-Group-ID-param =
"rksgroup"  EQUAL  RKS‑Group‑ID
RKS-Group-ID =
token
Charge-param =
"charge"  EQUAL  Acct‑Charge‑URI
Acct-Charge-URI =
LDQUOT  addr‑spec  RDQUOT
Calling-param =
"calling"  EQUAL  Acct‑Calling‑URI
Acct-Calling-URI =
LDQUOT  addr‑spec  RDQUOT
Called-param =
"called"  EQUAL  Acct‑Called‑URI
Acct-Called-URI =
LDQUOT  addr‑spec  RDQUOT
Routing-param =
"routing"  EQUAL  Acct‑Routing‑URI
Acct-Routing-URI =
LDQUOT  addr‑spec  RDQUOT
Loc-Routing-param =
"locroute"  EQUAL  Acct‑Loc‑Routing‑URI
Acct-Loc-Routing-URI =
LDQUOT  addr‑spec  RDQUOT
JIP-param =
"jip"  EQUAL  jip
jip =
LDQUOT  1*phonedigit‑hex  jip‑context  RDQUOT
jip-context =
";jip‑context="  jip‑descriptor
jip-descriptor =
global‑hex‑digits
global-hex-digits =
"+"  1*3( phonedigit )  *phonedigit‑hex
phonedigit =
DIGIT /  [ visual‑separator ]
phonedigit-hex =
HEXDIG /  "*" /  "#" /  [ visual‑separator ]
visual-separator =
"-" /  "." /  "(" /  ")"
Up
P-DCS-LAES =
"P-DCS-LAES"  HCOLON  Laes‑sig  *( SEMI  Laes‑param )
Laes-sig =
hostport
Laes-param =
Laes‑content /  Laes‑cccid /  Laes‑bcid  /  generic‑param
Laes-content =
"content"  EQUAL  hostport
Laes-cccid =
"cccid"  EQUAL  1*8( HEXDIG )
Laes-bcid  =
"cccid"  EQUAL   1*48( HEXDIG )
Up
P-DCS-OSPS =
"P-DCS-OSPS"  HCOLON  OSPS‑Tag
OSPS-Tag =
"BLV" /  "EI" /  "RING" /  token
Up
P-DCS-Redirect =
"P-DCS-Redirect"  HCOLON  Called‑ID  *( SEMI  redir‑params )
Called-ID =
LDQUOT  addr‑spec  RDQUOT
redir-params =
redir‑uri‑param /  redir‑count‑param /  generic‑param
redir-uri-param =
"redirector‑uri"  EQUAL  Redirector
Redirector =
LDQUOT  addr‑spec  RDQUOT
redir-count-param =
"count"  EQUAL  Redir‑count
Redir-count =
1*DIGIT
Up
P-DCS-Trace-Party-ID =
"P-DCS-Trace-Party-ID"  HCOLON  name‑addr
*1( SEMI  timestamp‑param )  *( SEMI  trace‑param )
timestamp-param =
"timestamp="  1*DIGIT  [ "."  1*DIGIT ]
trace-param =
generic‑param
Up
P-Early-Media =
"P-Early-Media"  HCOLON  [ em‑param  *( COMMA  em‑param) ]
em-param =
"sendrecv" /  "sendonly" /  "recvonly" /  "inactive" /  "gated" /  "supported" /  token
Up
P-Media-Authorization =
"P-Media-Authorization"  HCOLON  P‑Media‑Authorization‑Token  *( COMMA  P‑Media‑Authorization‑Token )
P-Media-Authorization-Token  =
1*HEXDIG
Up
PPreferredID =
"P-Preferred-Identity"  HCOLON  PPreferredID‑value  *( COMMA  PPreferredID‑value )

; example:
; P‑Preferred‑Identity: "Cullen Jennings" <sip:fluffy@cisco.com>

PPreferredID-value =
name‑addr /  addr‑spec
Up
PPreferredService =
"P-Preferred-Service"  HCOLON  PPreferredService‑value
PPreferredService-value =
Service‑ID  *( COMMA  Service‑ID )
Up
P-Private-Network-Indication =
"P-Private-Network-Indication"  HCOLON  PNI‑value  *( SEMI  PNI‑param )

; example:
; P-Private-Network-Indication: example.com

PNI-value =
generic‑param
PNI-param =
hostname
Up
P-Profile-Key =
"P-Profile-Key"  HCOLON  ( name‑addr /  addr‑spec )  *( SEMI  generic‑param )

; example:
; P‑Profile‑Key: <sip:chatroom-!.*!@example.com>

Up
P-Refused-URI-List =
"P-Refused-URI-List"  HCOLON  uri‑list‑entry  *( COMMA  uri‑list‑entry )
uri-list-entry =
( name‑addr /  addr‑spec )  *( SEMI  refused‑param )
refused-param =
members‑param /  generic‑param
members-param =
"members"  EQUAL  LDQUOT  *( qdtext /  quoted‑pair )  RDQUOT
Up
P-Served-User =
"P-Served-User"  HCOLON  PServedUser‑value  *( SEMI  served‑user‑param )
served-user-param =
sessioncase‑param / 
registration‑state‑param / 
generic‑param
PServedUser-value =
name‑addr /  addr‑spec
sessioncase-param =
"sescase"  EQUAL  ( "orig" /  "term" ) /  orig‑cdiv
registration-state-param =
"regstate"  EQUAL  "unreg" /  "reg"
orig-cdiv =
"orig‑cdiv"
Up
P-User-Database =
"P-User-Database"  HCOLON  database  *( SEMI  generic‑param )
database =
LAQUOT  DiameterURI   RAQUOT

;  Diameter‑URI is defined in   RFC 3588 – Section 4.3
; example:
; P-User-Database: <aaa://host.example.com;transport=tcp>

Up
P-Visited-Network-ID =
"P-Visited-Network-ID"  HCOLON  vnetwork‑spec  *( COMMA  vnetwork‑spec )

; example:
; P‑Visited‑Network‑ID: other.net, "Visited network number 1"

vnetwork-spec =
( token /  quoted‑string )  *( SEMI  vnetwork‑param )
vnetwork-param =
generic‑param
Up
Path =
"Path"  HCOLON  path‑value  *( COMMA  path‑value )

; example:
; Path: <sip:P3.EXAMPLEHOME.COM;lr>,<sip:P1.EXAMPLEVISITED.COM;lr>

path-value =
name‑addr  *( SEMI  rr‑param )
Up
Permission-Missing =
"Permission‑Missing"  HCOLON  per‑miss‑spec  *( COMMA  per‑miss‑spec )

; example:
; Permission‑Missing: sip:C@example.com

per-miss-spec =
( name‑addr /  addr‑spec )  *( SEMI  generic‑param )
Up
Policy-Contact =
"Policy‑Contact"  HCOLON  policyContact‑info  *( COMMA  policyContact‑info )
policyContact-info =
LAQUOT  policyContact-uri  RAQUOT  *( SEMI  policyContact‑param )
policyContact-uri =
( SIP‑URI /  SIPS‑URI /  absoluteURI )
policyContact-param =
( "non‑cacheable" /  policyContact‑alt‑uri /  generic‑param )
policyContact-alt-uri =
"alt‑uri"  EQUAL  hostname
Up
Policy-ID =
"Policy‑ID"  HCOLON  policyURI  *( COMMA  policyURI )
policyURI =
( SIP‑URI /  SIPS‑URI /  absoluteURI )  [ SEMI  token‑param ]  *( SEMI  generic‑param )
token-param =
"token="  token
Up
Priority =
"Priority"  HCOLON  priority‑value

; example:
; Priority: emergency

priority-value =
"emergency" /  "urgent" /  "normal" /  "non‑urgent" /  other‑priority
other-priority =
token
Up
priority-share =
"Priority‑Share"  HCOLON  priority‑share‑options  *( SEMI  generic‑param )
priority-share-options =
"allowed" /  "not‑allowed" /  other‑options
other-options =
token
Up
Privacy-hdr =
"Privacy"  HCOLON  priv‑value  *( ";"  priv‑value )

; example:
; Privacy: id

priv-value =
"header" /  "session" /  "user" /  "none" /  "critical" /  ; see RFC 3323
"id" /  ; see  RFC 3325 – Section 9.3
"history" /  ; see  RFC 7044 – Section 14.2
token
Up
Priv-Answer-Mode =
"Priv‑Answer‑Mode"  HCOLON  answer‑mode‑value  *( SEMI  answer‑mode‑param )

; example:
; Priv‑Answer‑Mode: Auto

Up
Proxy-Authenticate =
"Proxy‑Authenticate"  HCOLON  challenge

; example:
; Proxy‑Authenticate: Digest realm="atlanta.example.com", qop="auth",
;    nonce="f84f1cec41e6cbe5aea9c8e88d359",
;    opaque="", stale=FALSE, algorithm=MD5

challenge =
( "Digest"  LWS  digest‑cln  *( COMMA  digest‑cln ) ) /  other‑challenge
other-challenge =
auth‑scheme  LWS  auth‑param  *( COMMA  auth‑param )
digest-cln =
realm /  domain /  nonce /  opaque /  stale /  algorithm /  qop‑options /  auth‑param
realm =
"realm"  EQUAL  realm‑value
realm-value =
quoted‑string
domain =
"domain"  EQUAL  LDQUOT  URI  *( 1*SP  URI )  RDQUOT
URI =
absoluteURI /  abs‑path
nonce =
"nonce"  aka‑nonce  ( aka‑nonce /  nonce‑value )

; example: ; nonce rule is as amended by RFC 3310
; nonce="MzQ0a2xrbGtmbGtsZm9wb2tsc2tqaHJzZXNy9uQyMzMzMzQK="

aka-nonce =
LDQUOT  aka‑nonce‑value  RDQUOT
aka-nonce-value =
<base64 encoding of RAND, AUTN, and server specific data>
nonce-value =
quoted‑string
opaque =
"opaque"  EQUAL  quoted‑string
stale =
"stale"  EQUAL  ( "true" /  "false" )
algorithm =
"algorithm"  EQUAL  ( aka‑namespace /  algorithm‑value )

; example:
;  algorithm=AKAv1‑MD5

algorithm-value =
( "MD5" /  "MD5‑sess" /  token )
aka-namespace =
aka‑version  "-"  algorithm‑value
aka-version =
"AKAv"  1*DIGIT

; AKAv1  RFC 3310 – Section 3.1

; AKAv2  RFC 4169 – Section 5

qop-options =
"qop"  EQUAL  LDQUOT  qop‑value  *( ","  qop‑value )  RDQUOT
qop-value =
"auth" /  "auth‑int" /  token
Up
Proxy-Authorization =
"Proxy-Authorization"  HCOLON  credentials

; example:
; Proxy‑Authorization: Digest username="alice",
;   realm="atlanta.example.com",
;   nonce="wf84f1ceczx41ae6cbe5aea9c8e88d359", opaque="",
;   uri="sip:bob@biloxi.example.com",
;   response="42ce3cef44b22f50c6a6071bc8"

Up
Proxy-Require =
"Proxy‑Require"  HCOLON  option‑tag  *( COMMA  option‑tag )

; example:
; Proxy‑Require: sec‑agree

Up
RAck =
"RAck"  HCOLON  response‑num  LWS  CSeq‑num  LWS  Method

; example:
; RAck: 776656 1 INVITE

response-num =
1*DIGIT
CSeq-num =
1*DIGIT
Up
Reason =
"Reason"  HCOLON  reason‑value  *( COMMA  reason‑value )

; examples:
;  Reason: SIP;cause=200;text="Call completed elsewhere"
;  Reason: Q.850;cause=16;text="Terminated"
;  Reason: SIP;cause=600;text="Busy Everywhere"
;  Reason: SIP;cause=580;text="Precondition Failure"
;  Reason: preemption;cause=1;text="UA Preemption"
;  Reason: preemption;cause=2;text="Reserved Resources Preempted"
;  Reason: preemption;cause=3;text="Generic Preemption"
;  Reason: preemption;cause=4;text="Non-IP Preemption"

reason-value =
protocol  *( SEMI  reason‑params )
protocol =
"SIP" /  "Q.850" / 
"Preemption" /  ; see  RFC 4411 – Section 5
; the following in  3GPP TS 24.229 – Clause 7.2A.18
; -----
"EMM" /
; EPS Mobility Management
; see  3GPP TS 24.301 – subclause 9.9.3.9
"ESM" /
; EPS Session Management
; see  3GPP TS 24.301 – subclause 9.9.4.4
"S1AP-RNL" /
; Radio Network Layer
; see  3GPP TS 36.413
"S1AP-TL" /
; Transport Layer
; see  3GPP TS 36.413
"S1AP-NAS" /
; Non-Access Stratum
; see  3GPP TS 36.413
"S1AP-MISC" /
; Miscellaneous
; see  3GPP TS 36.413
"S1AP-PROT" /
; Protocol
; see  3GPP TS 36.413
"DIAMETER" /
"IKEV2" /
; see  3GPP TS 29.274 – subclause 8.103
"RELEASE_CAUSE" / 
; 1  User ends call
; 2  RTP/RTCP time-out
; 3  Media bearer loss
; 4  SIP timeout - no ACK
; 5  SIP response time-out
; 6  Call-setup time-out  
"FAILURE_CAUSE" / 
; 1  Media bearer or QoS lost
; 2  Release of signalling bearer
; 3  Indication of failed resources allocation  
; -----
token
reason-params =
protocol‑cause /  reason‑text /  isup‑cause‑location /  reason‑extension
protocol-cause =
"cause"  EQUAL  cause
cause =
1*DIGIT
reason-text =
"text"  EQUAL  quoted‑string
isup-cause-location =
"location"  EQUAL  isup-location-value
isup-location-value =
"U" /
  ; for  0 0 0 0  user
"LPN" /
  ; for  0 0 0 1  private network serving the local user
"LN" /
  ; for  0 0 1 0  public network serving the local user
"TN" /
  ; for  0 0 1 1  transit network
"RLN" /
  ; for  0 1 0 0  public network serving the remote user
"RPN" /
  ; for  0 1 0 1  private network serving the remote user
"LOC-6" /
  ; for  0 1 1 0  spare
"INTL" /
  ; for  0 1 1 1  international network
"LOC-8" /
  ; for  1 0 0 0  spare
"LOC-9" /
  ; for  1 0 0 1  spare
"BI" /
  ; for  1 0 1 0  network beyond interworking point
"LOC-11" /
  ; for  1 0 1 1  spare
"LOC-12" /
  ; for  1 1 0 0  reserved for national use
"LOC-13" /
  ; for  1 1 0 1  reserved for national use
"LOC-14" /
  ; for  1 1 1 0  reserved for national use
"LOC-15" /
  ; for  1 1 1 1  reserved for national use
reason-extension =
generic‑param
Up
Record-Route =
"Record‑Route"  HCOLON  rec‑route  *( COMMA  rec‑route )

; example:
; Record‑Route: <sip:ss2.biloxi.example.com;lr>,
;  <sip:ss1.atlanta.example.com;lr>

rec-route =
name‑addr  *( SEMI  rr‑param )
rr-param =
generic‑param
Up
Recv-Info =
"Recv‑Info"  HCOLON  [ Info‑package‑list ]

; example:
; Recv‑Info: P, R

Info-package-list =
Info‑package‑type  *( COMMA  Info‑package‑type )
Up
Refer-Events-At =
"Refer-Events-At"  HCOLON  LAQUOT  ( SIP‑URI /  SIPS‑URI )  RAQUOT  *( SEMI  generic‑param )

; example:
; Refer‑Events‑At: <sips:vPT3izGmo8NTxaPADRZvEAY22BKx@example.com;gr>

Up
Refer-Sub =
"Refer‑Sub"  HCOLON  refer‑sub‑value  *( SEMI  exten )
refer-sub-value =
"true" /  "false"
exten =
generic‑param
Up
Refer-To =
( "Refer‑To" /  "r" )  HCOLON  ( name‑addr /  addr‑spec )  *( SEMI  refer‑param )

; example:
; Refer-To: <sips:a8342043f@atlanta.example.com?Replaces=
;   12345601%40atlanta.example.com%3Bfrom‑tag%3D314159%3Bto‑tag%3D1234567>
; Refer-To: sip:conf44@example.com;isfocus

refer-param =
generic‑param /  feature‑param
Up
Referred-By =
( "Referred‑By" /  "b" )  HCOLON  referrer‑uri  *( SEMI  ( referredby‑id‑param /  generic‑param ) )

; example:
; Referred-By: <sip:referrer@referrer.example>
;   ;cid="abnf-20398823.2UWQFN309shb3@referrer.example"

referrer-uri =
( name‑addr /  addr‑spec )
referredby-id-param =
"cid"  EQUAL  sip‑clean‑msg‑id
sip-clean-msg-id =
LDQUOT  dot‑atom  "@"  ( dot‑atom /  host )  RDQUOT
dot-atom =
atom  *( "."  atom )
atom =
1*( alphanum /  "-" /  "!" /  "%" /  "*" /  "_" /  "+" /  "'" /  "`" /  "~" )
Up
Reject-Contact =
( "Reject‑Contact" /  "j" )  HCOLON  rc‑value  *( COMMA  rc‑value )

; example:
; Reject‑Contact: *;actor="msg‑taker";video

rc-value =
"*"  *( SEMI  rc‑params )
rc-params =
feature‑param /  generic‑param
Up
Replaces =
"Replaces"  HCOLON  callid  *( SEMI  replaces‑param )

; example:
; Replaces: 425928@bobster.example.org;to-tag=7743;from-tag=6472

replaces-param =
to‑tag /  from‑tag /  early‑flag /  generic‑param
to-tag =
"to‑tag"  EQUAL  token
from-tag =
"from‑tag"  EQUAL  token
early-flag =
"early-only"
Up
Reply-To =
"Reply‑To"  HCOLON  rplyto‑spec

; example:
; Reply‑To: Bob <sip:bob@biloxi.com>

rplyto-spec =
( name‑addr /  addr‑spec )  *( SEMI  rplyto‑param )
rplyto-param =
generic‑param
Up
Request-Disposition =
( "Request-Disposition" /  "d" )  HCOLON  directive  *( COMMA  directive )

; example:
; Request‑Disposition: proxy, recurse, parallel

directive =
proxy‑directive /  cancel‑directive /  fork‑directive /  recurse‑directive /  parallel‑directive /  queue‑directive
proxy-directive =
"proxy" /  "redirect"
cancel-directive =
"cancel" /  "no‑cancel"
fork-directive =
"fork" /  "no‑fork"
recurse-directive =
"recurse" /  "no‑recurse"
parallel-directive =
"parallel" /  "sequential"
queue-directive =
"queue" /  "no‑queue"
Up
Require =
"Require"  HCOLON  option‑tag  *( COMMA  option‑tag )

; example:
; Require: 100rel

Up
Resource-Priority =
"Resource‑Priority"  HCOLON  r‑value  *( COMMA  r‑value )

; example:
; Resource‑Priority: wps.3, dsn.flash

r-value =
namespace  "."  r‑priority
namespace =
token‑nodot
r-priority =
token‑nodot
token-nodot =
1*( alphanum /  "-" /  "!" /  "%" /  "*" /  "_" /  "+" /  "`" /  "'" /  "~" )
Up
relayed-charge =
"Relayed‑Charge"  HCOLON  relayed‑charge‑list
relayed-charge-list =
relayed‑charge‑item  *( COMMA  relayed‑charge‑item )
relayed-charge-item =
relay‑source  HCOLON  charge‑params *( SEMI  charge‑params )
relay-source =
"PCSCF" /  "SCSCF" /  "IBCF" /  "transitfunction" /  "ICSCF" /  other‑source
other-source =
token
Up
resource-share =
"Resource‑Share"  HCOLON  r‑s‑param
r-s-param =
r‑s‑supported /  r‑s‑no‑media‑sharing /  r‑s‑media‑sharing /  r‑s‑other
r-s-supported =
"supported"  [ SEMI  origin ]  *( SEMI  generic‑param )
r-s-no-media-sharing =
"no-media-sharing"  SEMI  origin  *( SEMI  generic‑param )
r-s-media-sharing =
"media-sharing"  SEMI  origin  SEMI  resource‑sharing‑rules  SEMI  timestamp  *( SEMI  generic‑param )
r-s-other =
other-status  *( SEMI  generic‑param )
other-status =
token
origin =
"session‑initiator" /  "session‑receiver" /  other‑origin
other-origin =
token
resource-sharing-rules =
"rules"  EQUAL  DQUOTE  resource‑sharing‑rule  *( COMMA  resource‑sharing‑rule )  DQUOTE 
resource-sharing-rule =
[ active-resource-sharing-rule ]
active-resource-sharing-rule =
new‑sharing‑key  COLON  [ existing‑sharing‑key‑list ]  COLON  directionality
*( COLON  generic‑rule‑param‑value )
new-sharing-key =
sharing‑key
existing-sharing-key-list =
sharing‑key  *( SLASH  sharing‑key )
directionality =
"UL" /  "DL" /  "UL‑DL" /  other‑directionality
other-directionality =
token
sharing-key =
token
generic-rule-param-value =
token
timestamp =
"timestamp"  EQUAL  1*DIGIT
Up
Response-Source =
"Response‑Source"  HCOLON  source‑info
source-info =
source‑params  *( SEMI  source‑params )
source-params =
source‑urn /  token
source-urn =
"fe"  EQUAL  LAQUOT  source‑urn‑val  RAQUOT
source-urn-val =
1*uric
Up
Restoration-Info =
"Restoration‑Info"  HCOLON  pcrf‑token /  reason /  generic‑param
pcrf-token =
( "IMSI" /  ext‑type )  EQUAL  pcrf‑param
pcrf-param =
quoted‑string
reason =
noresponse"
ext-type =
token
Up
Retry-After =
"Retry-After"  HCOLON  delta‑seconds  [ comment ]  *( SEMI  retry‑param )

; examples:
;  Retry‑After: 18000;duration=3600
;  Retry‑After: 120 (I'm in a meeting)

retry-param =
( "duration"  EQUAL  delta‑seconds ) /  generic‑param
Up
Route =
"Route"  HCOLON  route‑param  *( COMMA  route‑param )

; example:
; Route: <sip:ss1.atlanta.example.com;lr>,
;  <sip:ss2.biloxi.example.com;lr>

route-param =
name‑addr  *( SEMI  rr‑param )
Up
RSeq =
"RSeq"  HCOLON  response‑num

; example:
; RSeq: 988789

Up
Security-Client =
"Security‑Client"  HCOLON  sec‑mechanism  *( COMMA  sec‑mechanism )
sec-mechanism =
mechanism‑name  *( SEMI  mech‑parameters )
mechanism-name =
(
"digest" /  "tls" /  "ipsec‑ike" /  "ipsec‑man" /  ; see  Section 2.2
"ipsec-3gpp" /  ; see  Appendix A
sdes‑srtp‑name /  msrp‑tls‑name /  bfcp‑tls‑name /  udptl‑dtls‑name / 
; see  3GPP TS 24.229 – Section 7.2A.7
token
 )
sdes-srtp-name =
"sdes‑srtp"
msrp-tls-name =
"msrp‑tls"
bfcp-tls-name =
"bfcp‑tls"
udptl-dtls-name =
"udptl‑dtls"
mech-parameters =
(
preference /  digest‑algorithm /  digest‑qop /  digest‑verify /  ; see  Section 2.2
algorithm /  protocol /  mode /  encrypt‑algorithm /  spi /  port1 /  port2 /  ; see  Appendix A
spi‑c /  spi‑s /  port‑c /  port‑s /  ; see  3GPP TS 33.203 – Annex H
mediasec‑param /  ; see  3GPP TS 24.229 – Section 7.2A.7
extension
 )
preference =
"q"  EQUAL  qvalue
digest-algorithm =
"d-alg"  EQUAL  token
digest-qop =
"d-qop"  EQUAL  token
digest-verify =
"d-ver"  EQUAL  LDQUOT  32LHEX  RDQUOT
algorithm =
"alg"  EQUAL  ( "hmac‑md5‑96" /  "hmac‑sha‑1‑96" )
protocol =
"prot"  EQUAL  ( "ah" /  "esp" )
mode =
"mod"  EQUAL  (
"trans" /  "tun" / 
"UDP-enc-tun"  ; see  3GPP TS 33.203 – Annex H
 )
encrypt-algorithm =
"ealg"  EQUAL  (
"des‑ede3‑cbc" /  "null" / 
"aes‑cbc"  ; see  3GPP TS 33.203 – Annex H
 )
spi =
"spi"  EQUAL  spivalue
spi-c =
"spi‑c"  EQUAL  spivalue
spi-s =
"spi‑s"  EQUAL  spivalue
spivalue =
10DIGIT
; 0 to 4294967295
port1 =
"port1"  EQUAL  port
port2 =
"port2"  EQUAL  port
port-c =
"port‑c"  EQUAL  port
port-s =
"port‑s"  EQUAL  port
port =
1*DIGIT
mediasec-param =
"mediasec"
extension =
generic‑param
Up
Security-Server =
"Security‑Server"  HCOLON  sec‑mechanism  *( COMMA  sec‑mechanism )

; example:
; Security-Server: ipsec-ike;q=0.1

Up
Security-Verify =
"Security‑Verify"  HCOLON  sec‑mechanism  *( COMMA  sec‑mechanism )

; example:
; Security‑Verify: tls;q=0.2

Up
Server =
"Server"  HCOLON  server‑val  *( LWS  server‑val )

; example:
; Server: HomeServer v2

server-val =
product /  comment
product =
token  [ SLASH  product‑version ]
product-version =
token
Up
Service-Interact-Info =
"Service‑Interact‑Info"  HCOLON  executed‑service‑params  *( COMMA  executed‑service‑params )
executed-service-params =
executed‑service /  avoid‑service
executed-service =
"executed-service"  EQUAL  service‑spec
avoid-service =
"avoid-service"  EQUAL  service‑spec
service-spec =
service‑id  *( SEMI  service‑param )
service-id =
token /  quoted‑string
service-param =
generic‑param
Up
Service-Route =
"Service‑Route"  HCOLON  sr‑value  *( COMMA  sr‑value )

; example:
; Service‑Route: <sip:P2.HOME.EXAMPLE.COM;lr>,
;    <sip:HSP.HOME.EXAMPLE.COM;lr>

sr-value =
name‑addr  *( SEMI  rr‑param )
Up
Session-Expires =
( "Session‑Expires" /  "x" )  HCOLON  delta‑seconds  *( SEMI  se‑params )

; example:
; Session‑Expires: 4000;refresher=uac

se-params =
refresher‑param /  generic‑param
refresher-param =
"refresher"  EQUAL  ( "uas" /  "uac" )
Up
Session-ID =
"Session‑ID"  HCOLON  session‑id‑value
session-id-value =
local‑uuid  *( SEMI  sess‑id‑param )
local-uuid =
sess‑uuid /  nil
remote-uuid =
sess‑uuid /  nil
sess-uuid =
32 ( DIGIT /  %x61‑66 )
;  32 chars of [0‑9a‑f]
sess-id-param =
remote-param /  logme-param /  generic‑param
remote-param =
"remote"  EQUAL  remote‑uuid
logme-param =
"logme"
nil =
32 ( "0" )
Up
SIP-ETag =
"SIP‑ETag"  HCOLON  entity‑tag

; example:
; SIP‑ETag: dx200xyz

entity-tag =
token
Up
SIP-If-Match =
"SIP‑If‑Match"  HCOLON  entity‑tag

; example:
; SIP‑If‑Match: dx200xyz

Up
Subject =
( "Subject" /  "s" )  HCOLON  [ TEXT‑UTF8‑TRIM ]

; example:
; Subject: A tornado is heading our way!

Up
Subscription-State =
"Subscription‑State"  HCOLON  substate‑value  *( SEMI  subexp‑params )

; example:
; Subscription‑State: active;expires=60

substate-value =
"active" /  "pending" /  "terminated" /  extension‑substate
extension-substate =
token
subexp-params =
( "reason"  EQUAL  event‑reason‑value )  /
( "expires"  EQUAL  delta‑seconds )  /
( "retry‑after"  EQUAL  delta‑seconds )  /
max‑rate‑param /  min‑rate‑param /  amin‑rate‑param /  generic‑param
event-reason-value =
"deactivated" /  "probation" /  "rejected" /  "timeout" /  "giveup" /  "noresource" /  "invariant" /  event‑reason‑extension
event-reason-extension  =
token
Up
Supported =
( "Supported" /  "k" )  HCOLON  [ option‑tag  *( COMMA  option‑tag ) ]

; example:
; Supported: replaces

Up
Suppress-If-Match =
"Suppress‑If‑Match"  HCOLON  entity‑tag

; example:
; Suppress‑If‑Match: dx200xyz

Up
Target-Dialog =
"Target‑Dialog"  HCOLON  callid  *( SEMI  td‑param )
td-param =
remote‑param /  local‑param /  generic‑param
remote-param =
"remote‑tag"  EQUAL  token
local-param =
"local‑tag"  EQUAL  token
Up
Timestamp =
"Timestamp"  HCOLON  1*( DIGIT )  [ "."  *( DIGIT ) ]  [ LWS  delay ]

; example:
; Timestamp: 54

delay =
*( DIGIT )  [ "."  *( DIGIT ) ]
Up
To =
( "To" /  "t" )  HCOLON  ( name‑addr /  addr‑spec )  *( SEMI  to‑param )

; example:
; To: Bob <sip:bob@biloxi.example.com>;tag=8321234356

to-param =
tag‑param /  generic‑param
Up
Trigger-Consent =
"Trigger-Consent"  HCOLON  trigger-cons-spec  *( COMMA  trigger-cons-spec )

; example:
; Trigger-Consent: sip:123@relay.example.com
;     ;target-uri="sip:friends@relay.example.com"

trigger-cons-spec =
( SIP‑URI /  SIPS‑URI )  *( SEMI  trigger‑param )
trigger-param =
target‑uri /  generic‑param
target-uri =
"target‑uri"  EQUAL  LDQUOT  *( qdtext /  quoted‑pair )  RDQUOT
Up
Unsupported =
"Unsupported"  HCOLON  option‑tag  *( COMMA  option‑tag )

; example:
; Unsupported: 100rel

Up
User-Agent =
"User‑Agent"  HCOLON  server‑val  *( LWS  server‑val )

; example:
; User‑Agent: Softphone Beta1.5

Up
UUI =
"User‑to‑User"  HCOLON  uui‑value  *( COMMA  uui‑value )
uui-value =
uui‑data  *( SEMI  uui‑param )
uui-param =
token /  quoted‑string
uui-data =
pkg‑param  /  cont‑param /  enc‑param /  generic‑param
pkg-param =
"purpose"  EQUAL  pkg‑param‑value
pkg-param-value =
"isdn‑uui" /  ; see  RFC 7434 – Section 11
token
cont-param =
"content"  EQUAL  cont‑param‑value
cont-param-value =
"isdn-uui" /  ; see  RFC 7434 – Section 11
token
enc-param =
"encoding"  EQUAL  enc‑param‑value
enc-param-value =
token /  "hex" 
Up
Via =
( "Via" /  "v" )  HCOLON  via‑parm  *( COMMA  via‑parm )
via-parm =
sent‑protocol  LWS  sent‑by  *( SEMI  via‑params )
sent-protocol =
protocol‑name  SLASH  protocol‑version  SLASH  transport
sent-by =
host  [ COLON  port ]
protocol-name =
"SIP" /  token
protocol-version =
token
transport =
"UDP" /  "TCP" /  "TLS" /  "SCTP" /  ; see  RFC 3261
"TLS-SCTP" /  ; see  RFC 4168 – Section 4
"WS" /  "WSS" /  ; see  RFC 7118 – Section 5.1
other-transport
via-params =
via‑ttl /  via‑maddr /  via‑branch /  ; see  RFC 3261
via‑received /  ; see  RFC 3261,   RFC 7118 – Section 5.3
via‑compression /  ; see  RFC 3486 – Section 8
response‑port /  ; see  RFC 3581 – Section 5
via‑sip‑sigcomp‑id /  ; see  RFC 5049 – Section 9.1
via‑alias /  ; see  RFC 5923 – Section 7
via‑keep /  ; see  RFC 6223 – Section 8
oc /  oc‑validity /  oc‑seq /  oc‑algo /  ; see  RFC 7339 – Section 9
received‑realm /  ; see  RFC 8055 – Section 5.6.2
via‑extension
via-ttl =
"ttl"  EQUAL  ttl
via-maddr =
"maddr"  EQUAL  host
via-received =
"received"  EQUAL  ( IPv4address /  IPv6address )
via-branch =
"branch"  EQUAL  token
via-compression =
"comp"  EQUAL  ( "sigcomp" /  other‑compression )
response-port =
"rport"  [ EQUAL  1*DIGIT ]
via-sip-sigcomp-id =
"sigcomp-id"  EQUAL  LDQUOT  *( qdtext /  quoted‑pair )  RDQUOT
via-alias =
"alias"
via-keep =
"keep"  [ EQUAL  1*( DIGIT ) ]
oc =
"oc"  [ EQUAL  oc‑num ]
oc-validity =
"oc‑validity"  [ EQUAL  delta‑ms ]
oc-seq =
"oc‑seq"  EQUAL  1*12DIGIT  "."  1*5DIGIT
oc-algo =
"oc‑algo"  EQUAL  DQUOTE  algo‑list  *( COMMA  algo‑list )  DQUOTE
received-realm =
"received‑realm"  EQUAL  LDQUOT  op‑id  COLON  jws  LDQUOT
ttl =
1*3DIGIT     ; 0 to 255
other-compression =
token
oc-num =
1*DIGIT
algo-list =
"loss"  /
"rate"  /     ; see  RFC 7415 – Section 5
*( other‑algo )
other-algo =
%x41‑5A /  %x61‑7A /  %x30‑39
delta-ms =
1*DIGIT
op-id =
token
jws =
header  ".."  signature
header =
1*base64‑char 
signature =
1*base64‑char 
base64-char =
ALPHA /  DIGIT /  "/" /  "+"
via-extension =
generic‑param
Up
Warning =
"Warning"  HCOLON  warning‑value  *( COMMA  warning‑value )

; example:
; Warning: 301 isi.edu "Incompatible network address type 'E.164'"

warning-value =
warn‑code  SP  warn‑agent  SP  warn‑text
warn-code =
3DIGIT

; 300  Incompatible network protocol:
; One or more network protocols contained in the session description are not available.

; 301  Incompatible network address formats:
; One or more network address formats contained in the session description are not available.

; 302  Incompatible transport protocol:
; One or more transport protocols described in the session description are not available.

; 303  Incompatible bandwidth units:
; One or more bandwidth measurement units contained in the session description were not understood.

; 304  Media type not available:
; One or more media types contained in the session description are not available.

; 305  Incompatible media format:
; One or more media formats contained in the session description are not available.

; 306  Attribute not understood:
; One or more of the media attributes in the session description are not supported.

; 307  Session description parameter not understood:
; A parameter other than those listed above was not understood.

; 308  Incompatible language specification:
; Requested languages not supported. Supported languages are [list of supported languages]; supported media are: [list of supported media].
; [RFC 8373]

; 330  Multicast not available:
; The site where the user is located does not support multicast.

; 331  Unicast not available:
; The site where the user is located does not support unicast communication (usually due to the presence of a firewall).

; 370  Insufficient bandwidth:
; The bandwidth specified in the session description or defined by the media exceeds that known to be available.

; 380  SIPS Not Allowed:
; The bandwidth specified in the session description or defined by the media exceeds that known to be available.
; [RFC 5630]

; 381  SIPS Required:
; The UAS or proxy cannot process the request because the SIPS scheme is required.
; [RFC 5630]

; 399  Miscellaneous warning:
; The warning text can include arbitrary information to be presented to a human user or logged. A system receiving this warning MUST NOT take any automated action.

warn-agent =
hostport /  pseudonym
warn-text =
quoted‑string
pseudonym =
token
Up
WWW-Authenticate =
"WWW-Authenticate"  HCOLON  challenge

; SIP example:
; WWW‑Authenticate: Digest realm="atlanta.example.com", qop="auth",
;   nonce="84f1c1ae6cbe5ua9c8e88dfa3ecm3459",
;   opaque="", stale=FALSE, algorithm=MD5

auth-param =
1#( integrity‑key /  cipher‑key )
integrity-key =
"ik"  EQUAL  ik‑value
cipher-key =
"ck"  EQUAL  ck‑value
ik-value =
LDQUOT  *( HEXDIG )  RDQUOT
ck-value =
LDQUOT  *( HEXDIG )  RDQUOT

; IMS example:
; SIP/2.0 401 Unauthorized
; ...
; WWW-Authenticate: Digest realm="registrar.home1.net",
;   nonce=base64(RAND + AUTN + server specific data),
;   algorithm=AKAv1‑MD5,
;   ik="00112233445566778899aabbccddeeff",
;   ck="ffeeddccbbaa11223344556677889900"
; CSeq: 1 REGISTER

Up
Status-Code =
Informational /  Success /  Redirection /  Client‑Error /  Server‑Error /  Global‑Failure /  extension‑code
extension-code =
3DIGIT
Informational =
"100" /   ; Trying   §21.1.1
"180" /   ; Ringing   §21.1.2
"181" /   ; Call Is Being Forwarded   §21.1.3
"182" /   ; Queued   §21.1.4
"183" /   ; Session Progress   §21.1.5
"199"  ; Early Dialog Terminated   RFC 6228 – Section 11.1
Success =
"200" /   ; OK   §21.2.1
"202" /   ; Accepted (Deprecated)   RFC 6665 – Section 8.3.1
"204"  ; No Notification   RFC 5839 – Section 8.1
Redirection =
"300" /   ; Multiple Choices   §21.3.1
"301" /   ; Moved Permanently   §21.3.2
"302" /   ; Moved Temporarily   §21.3.3
"305" /   ; Use Proxy   §21.3.4
"380"  ; Alternative Service   §21.3.5
Client-Error =
"400" /   ; Bad Request   §21.4.1
"401" /   ; Unauthorized   §21.4.2
"402" /   ; Payment Required   §21.4.3
"403" /   ; Forbidden   §21.4.4
"404" /   ; Not Found   §21.4.5
"405" /   ; Method Not Allowed   §21.4.6
"406" /   ; Not Acceptable   §21.4.7
"407" /   ; Proxy Authentication Required   §21.4.8
"408" /   ; Request Timeout   §21.4.9
"410" /   ; Gone   §21.4.10
"412" /   ; Conditional Request Failed   RFC 3903 – Section 13.2
"413" /   ; Request Entity Too Large   §21.4.11
"414" /   ; Request-URI Too Long   §21.4.12
"415" /   ; Unsupported Media Type   §21.4.13
"416" /   ; Unsupported URI Scheme   §21.4.14
"417" /   ; Unknown Resource-Priority   RFC 4412 – Section 12.4
"420" /   ; Bad Extension   §21.4.15
"421" /   ; Extension Required   §21.4.16
"422" /   ; Session Interval Too Small   RFC 4028 – Section 12.2
"423" /   ; Interval Too Brief   §21.4.17
"424" /   ; Bad Location Information   RFC 6442 – Section 8.4
"425" /   ; Bad Alert Message   RFC 8876 – Section 10.3
"428" /   ; Use Identity Header   RFC 4474 – Section 14.2
"429" /   ; Provide Referrer Identity   RFC 3892 – Section 8
"430" /   ; Flow Failed   RFC 5626 – Section 11.5
"433" /   ; Anonymity Disallowed   RFC 5079 – Section 6
"436" /   ; Bad Identity Info   RFC 8224 – Section 13.2
"437" /   ; Unsupported Credential   RFC 8224 – Section 13.2
"438" /   ; Invalid Identity Header   RFC 4474 – Section 14.5 – Section 14.2
"439" /   ; First Hop Lacks Outbound Support   RFC 5626 – Section 11.6
"440" /   ; Max-Breadth Exceeded   RFC 5393 – Section 6.2
"469" /   ; Bad Info Package   RFC 6086 – Section 11.6
"470" /   ; Consent Needed   RFC 5360 – Section 6.1
"480" /   ; Temporarily Unavailable   §21.4.18
"481" /   ; Call/Transaction Does Not Exist   §21.4.19
"482" /   ; Loop Detected   §21.4.20
"483" /   ; Too Many Hops   §21.4.21
"484" /   ; Address Incomplete   §21.4.22
"485" /   ; Ambiguous   §21.4.23
"486" /   ; Busy Here   §21.4.24
"487" /   ; Request Terminated   §21.4.25
"488" /   ; Not Acceptable Here   §21.4.26
"489" /   ; Bad Event   RFC 6665 – Section 8.3.2
"491" /   ; Request Pending   §21.4.27
"493" /   ; Undecipherable   §21.4.28
"494"  ; Security Agreement Required   RFC 3329 – Section 6.4
Server-Error =
"500" /   ; Server Internal Error   §21.5.1
"501" /   ; Not Implemented   §21.5.2
"502" /   ; Bad Gateway   §21.5.3
"503" /   ; Service Unavailable   §21.5.4
"504" /   ; Server Time-out   §21.5.5
"505" /   ; Version Not Supported   §21.5.6
"513" /   ; Message Too Large   §21.5.7
"555" /   ; Push Notification Service Not Supported   RFC 8599 – Section 8.1
"580"  ; Precondition Failure   RFC 3312 – Section 8
Global-Failure =
"600" /   ; Busy Everywhere   §21.6.1
"603" /   ; Decline   §21.6.2
"604" /   ; Does Not Exist Anywhere   §21.6.3
"606" /   ; Not Acceptable   §21.6.4
"607" /   ; Unwanted   RFC 8197 – Section 5
"608"  ; Rejected   RFC 8688 – Section 5
Top
SIP-URI =
"sip:"   [ userinfo ]  hostport  uri‑parameters  [ headers ]
SIPS-URI =
"sips:"  [ userinfo ]  hostport  uri‑parameters  [ headers ]
Top
userinfo =
( user /  telephone‑subscriber )  [ ":"  password ]  "@"

; examples:
;   sip:alice@atlanta.com
;   sip:alice:secretword@atlanta.com;transport=tcp
;   sip:+1-212-555-1212:1234@gateway.com;user=phone

user  =
1*( unreserved /  escaped /  user-unreserved )
user-unreserved =
"&" /  "=" /  "+" /  "$" /  "," /  ";" /  "?" /  "/"
password =
*( unreserved /  escaped /  "&" /  "=" /  "+" /  "$" /  "," )
Up
hostport =
host  [ ":"  port ]

; examples:
;   sip:alice@atlanta.com
;   sip:alice:secretword@atlanta.com;transport=tcp
;   sip:+1-212-555-1212:1234@gateway.com;user=phone
;   sip:alice@192.0.2.4

host =
hostname /  IPv4address /  IPv6reference
hostname =
*( domainlabel  "." )  toplabel  [ "." ]
domainlabel =
alphanum /  alphanum  *( alphanum /  "-" )  alphanum
toplabel =
ALPHA /  ALPHA  *( alphanum /  "-" )  alphanum
IPv6reference =
"["  IPv6address  "]"
IPv6address =
;  as updated by:   RFC 5954 – Section 4.1
6( h16  ":" )  ls32  /
"::"  5( h16  ":" )  ls32  /
[ h16 ]  "::"  4( h16  ":" )  ls32  /
[ *1( h16  ":" )  h16 ]  "::"  3( h16  ":" )  ls32  /
[ *2( h16  ":" )  h16 ]  "::"  2( h16  ":" )  ls32  /
[ *3( h16  ":" )  h16 ]  "::"  h16  ":"    ls32  /
[ *4( h16  ":" )  h16 ]  "::"  ls32  /
[ *5( h16  ":" )  h16 ]  "::"  h16  /
[ *6( h16  ":" )  h16 ]  "::"
h16 =
1*4HEXDIG
ls32 =
( h16   ":"   h16 ) /  IPv4address
IPv4address =
dec-octet  "."  dec-octet  "."  dec-octet  "."  dec-octet
dec-octet =
DIGIT /  ; 0‑9
%x31‑39   DIGIT /  ; 10‑99
"1"  2DIGIT /  ; 100‑199
"2"  %x30‑34   DIGIT /  ; 200‑249
"25"  %x30‑35  ; 250‑255
port =
1*DIGIT
Up
uri-parameters =
*( ";"  uri-parameter )
uri-parameter =
transport‑param /  user‑param /  method‑param /  ; RFC 3261
ttl‑param /  maddr‑param /  lr‑param /  ; RFC 3261
compression‑param /  ; RFC 3486
annc‑parameters /  dialog‑parameters /  ; RFC 4240
target‑param /  cause‑param /  ; RFC 4458
uri‑sip‑sigcomp‑id /  ; RFC 5049
dialog‑param /  ; RFC 5552
maxage‑param /  maxstale‑param /  method‑param /  ; RFC 5552
postbody‑param /  ccxml‑param /  aai‑param /  ; RFC 5552
ob-param /  ; RFC 5626
gr‑param /  ; RFC 5627
bnc‑param /  sg‑param /  ; RFC 6140
m-param /  ; RFC 6910
iotl-param /  ; RFC 7549
pn-param /  ; RFC 8599
pn-prid /  ; RFC 8599
pn-provider /  ; RFC 8599
pn-purr /  ; RFC 8599
orig /  ; 3GPP TS 24.229
sos-param /  ; 3GPP TS 24.229
other-param
other-param =
pname  [ "="  pvalue ]
pname =
1*paramchar
pvalue =
1*paramchar
paramchar =
param-unreserved /  unreserved /  escaped
param-unreserved =
"[" /  "]" /  "/" /  ":" /  "&" /  "+" /  "$"
transport-param =
"transport="  (
"udp" /  "tcp" /  "sctp" /  "tls" / 
"ws"     ; WebSocket:   see  RFC 7118
other-transport )

; example:
;   sip:alice:secretword@atlanta.com;transport=tcp

other-transport =
token
Up
user-param =
"user="  (
"phone" /  "ip" / 
"dialstring" /  ; see  RFC 4967
other-user )

; example:
;   sip:1-212-555-1212:1234@gateway.com;user=phone

other-user =
token
dialstring =
dialstring-digits  context
dialstring-digits =
*dialstring‑element  dialstring‑digit   *dialstring‑element
dialstring-digit =
HEXDIG /  "*" /  "#"
dialstring-element =
dialstring-digit /  "P" /  "X" /  visual‑separator

; example:
;   sip:123;phone-context=atlanta.example.com@example.com;user=dialstring

Up
method-param =
"method="   Method

; example:
;   sip:atlanta.com;method=REGISTER?to=alice%40atlanta.com

Up
ttl-param =
"ttl="   ttl

; example:
;   sip:alice@atlanta.com;maddr=239.255.255.1;ttl=15

maddr-param =
"maddr="   host

; example:
;   sip:alice@atlanta.com;maddr=239.255.255.1;ttl=15

lr-param =
"lr"

; example:
;   Route: <sip:ss2.biloxi.example.com;lr>

compression-param =
"comp="   ( "sigcomp" /  other‑compression )

; example:
;   sip:alice@atlanta.com;comp=sigcomp

other-compression =
token
ANNC-URL =
sip‑ind  annc‑ind  "@"  hostport  annc‑parameters  uri‑parameters

; example:
;   sip:annc@ms.example.net; \
;       play=file://fs.example.net//clips/my-intro.dvi; \
;       content-type=video/mpeg%3bencode%d3314M-25/625-50

sip-ind =
"sip:" /  "sips:"
annc-ind =
"annc"
annc-parameters =
";"  play‑param
[ ";"  delay‑param ]
[ ";"  duration‑param ]
[ ";"  repeat‑param ]
[ ";"  locale‑param ]
[ ";"  variable‑params ]
[ ";"  extension‑params ]
play-param =
"play="  prompt‑url
prompt-url =
"/provisioned/"  announcement‑id
announcement-id =
1*( ALPHA /  DIGIT )
content-param =
"content‑type="  MIME‑type
delay-param =
"delay="  delay‑value
delay-value =
1*DIGIT
duration-param =
"duration="  duration‑value
duration-value =
1*DIGIT
repeat-param =
"repeat="  repeat‑value
repeat-value =
1*DIGIT /  "forever"
locale-param =
"locale="  token
variable-params =
param‑name  "="  variable‑value
param-name =
"param"  DIGIT
variable-value =
1*( ALPHA /  DIGIT )
extension-params =
extension-param  [ ";"  extension‑params ]
extension-param =
token  "="  token
Up
DIALOG-URL =
sip-ind  dialog-ind  "@"  hostport  dialog‑parameters
dialog-ind =
"dialog"
dialog-parameters =
";"  dialog‑param  [ vxml‑parameters ]  [ uri‑parameters ]
dialog-param =
"voicexml="  vxml‑url
vxml-parameters =
vxml‑param  [ vxml‑parameters ]
vxml-param =
";"  vxml‑keyword  "="  vxml‑value
vxml-keyword =
token
vxml-value =
token
target-param =
"target"   EQUAL   pvalue

; example:
;   sip:voicemail@example.com;target=bob%40example.com;cause=486

cause-param =
"cause"   EQUAL   Status-Code

; 404     Unknown/Not available
; 486     User busy
; 408     No reply
; 302     Unconditional
; 487     Deflection during alerting
; 480     Deflection immediate response
; 503     Mobile subscriber not reachable
; 380     Service number translation   RFC 8119 – Section 2
; example:
;   sip:voicemail@example.com;target=bob%40example.com;cause=486

uri-sip-sigcomp-id =
"sigcomp-id"   "="  1*paramchar
dialog-param =
"voicexml="  vxml-url     ;  vxml-url follows the URI syntax defined in RFC 3986
maxage-param =
"maxage="  1*DIGIT
maxstale-param =
"maxstale="  1*DIGIT
method-param =
"method="  ( "get" /  "post" )
postbody-param =
"postbody="  token
ccxml-param =
"ccxml="  json‑value
aai-param =
"aai="  json‑value
json-value =
false /  null /  true /  object /  array /  number /  string
;  defined in   RFC 7159

; example:
;   sip:dialog@mediaserver.example.com; \
;       voicexml=http://appserver.example.com/promptcollect.vxml; \
;       maxage=3600;maxstale=0

ob-param =
"ob"

; example:
;   NOTIFY sip:192.0.2.2;transport=tcp;ob SIP/2.0

gr-param =
"gr"   [ "="  pvalue ]

; examples:
;   sip:alice@example.com;gr=kjh29x97us97d
;   sip:asd887f9dfkk76690@example.com;gr

bnc-param =
"bnc"

; example:
;   Contact: <sip:198.51.100.3:5060;bnc>

sg-param =
"sg"

; example:
;   INVITE sip:+12145550102@198.51.100.3;sg=00:05:03:5e:70:a6 SIP/2.0

m-param =
"m="  ( "BS" /  "NR" /  "NL" )

; example:
;   SUBSCRIBE sip:456@b.com;m=NR

iotl-param =
iotl‑tag  "="  iotl‑value  [ "."  iotl‑value ]
iotl-tag =
"iotl"
iotl-value =
"homea‑homeb" /  "homeb‑visitedb" /  "visiteda‑homea" /  "visiteda‑homea" /  "homea‑visiteda" /  "visiteda‑homeb" /  other‑iotl
other-iotl =
1*iotl‑char
iotl-char =
alphanum /  "-"
pn-provider =
"pn-provider"   [ EQUAL   pvalue ]
pn-param =
"pn-param"   EQUAL   pvalue
pn-prid =
"pn-prid"   EQUAL   pvalue

pn-purr =
"pn-purr"   EQUAL   pvalue
orig =
"orig"
sos-param =
"sos"
headers =
"?"  header  *( "&"  header )

; examples:
;   sip:atlanta.com;method=REGISTER?to=alice%40atlanta.com
;   sips:alice@atlanta.com?subject=project%20x&priority=urgent

header =
hname  "="  hvalue
hname =
1*( hnv-unreserved /  unreserved /  escaped )
hvalue =
*( hnv-unreserved /  unreserved /  escaped )
hnv-unreserved =
"[" /  "]" /  "/" /  "?" /  ":" /  "+" /  "$"
absoluteURI =
scheme  ":"  ( hier‑part /  opaque‑part )
scheme =
ALPHA  *( ALPHA /  DIGIT /  "+" /  "-" /  "." )
hier-part =
( net‑path /  abs‑path )  [ "?"  query ]
net-path =
"//"  authority  [ abs‑path ]
abs-path =
"/"  path‑segments
query =
*uric
authority =
srvr /  reg‑name
srvr =
[  [ userinfo]  hostport ]
reg-name =
1*( unreserved /  escaped /  "$" /  "," /  ";" /  ":" /  "@" /  "&" /  "=" /  "+" )
path-segments =
segment  *( "/"  segment )
segment =
*pchar  *( ";"  param )
param =
*pchar
pchar =
unreserved /  escaped /  ":" /  "@" /  "&" /  "=" /  "+" /  "$" /  ","
opaque-part =
uric-no-slash  *uric
uric =
reserved /  unreserved /  escaped
uric-no-slash =
unreserved /  escaped /  ";" /  "?" /  ":" /  "@" /  "&" /  "=" /  "+" /  "$" /  ","
telephone-uri =
"tel:"  telephone‑subscriber

; examples:
;   tel:+1-201-555-0123
;   tel:7042;phone-context=example.com
;   tel:863-1234;phone-context=+1-914-555

telephone-subscriber =
global‑number /  local‑number
global-number =
global‑number‑digits  *par
global-number-digits =
"+"  *phonedigit  DIGIT  *phonedigit
phonedigit =
DIGIT /  [ visual‑separator ]
local-number =
local-number-digits  *par  context  *par
local-number-digits =
*phonedigit-hex  ( HEXDIG /  "*" /  "#" )  *phonedigit‑hex
phonedigit-hex =
HEXDIG /  "*" /  "#" /  [ visual‑separator ]
context =
";phone-context="  descriptor
descriptor =
domainname  /  global‑number‑digits
domainname =
*( domainlabel  "." )  toplabel  [ "." ]
domainlabel =
alphanum /  alphanum  *( alphanum /  "-" )  alphanum
toplabel =
ALPHA /  ALPHA  *( alphanum /  "-" )  alphanum
par =
parameter /  extension /  isdn‑subaddress /  ; see   RFC 3966
rn /  cic /  npdi /  ; see  RFC 4694 – Section 4
isub‑encoding /  ; see  RFC 4715 – Section 5
enum‑dip‑indicator /  ; see  RFC 4759 – Section 3
trunk‑group /  trunk‑context /  ; see  RFC 4904 – Section 5
premrate /  ; see  3GPP TS 24.229 – Section 7.2A.17
verstat  ; see  3GPP TS 24.229 – Section 7.2A.20
parameter =
";"  pname  [ "="  pvalue ]
pname =
1*( alphanum /  "-" )
pvalue =
1*paramchar
paramchar =
param-unreserved /  unreserved /  pct‑encoded
param-unreserved =
"[" /  "]" /  "/" /  ":" /  "&" /  "+" /  "$"
extension =
";ext="  1*phonedigit
isdn-subaddress =
";isub="  1*uric
uric =
reserved /  unreserved /  pct‑encoded
rn =
";rn="  ( global‑rn /  local‑rn )
cic =
";cic="  ( global-cic /  local‑cic )
npdi =
";npdi"
global-rn =
global-hex-digits
local-rn =
1*hex-phonedigit   rn‑context
rn-context =
";rn-context="  rn‑descriptor
rn-descriptor =
domainname /  global-hex-digits
global-hex-digits =
"+"  1*3( DIGIT )  *hex‑phonedigit
hex-phonedigit =
HEXDIG /  visual‑separator
global-cic =
global‑hex‑digits
local-cic =
1*hex-phonedigit  cic‑context
cic-context =
";cic-context="  rn‑descriptor
isub-encoding =
isub-encoding-tag  "="  isub‑encoding‑value
isub-encoding-tag =
"isub-encoding"
isub-encoding-value =
"nsap-ia5" /  "nsap-bcd" /  "nsap" /  token
enum-dip-indicator =
";enumdi"
trunk-group =
";tgrp="  trunk‑group‑label
trunk-context =
";trunk-context="  descriptor
trunk-group-label =
1*( unreserved /  escaped /  trunk‑group‑unreserved )
trunk-group-unreserved =
"/" /  "&" /  "+" /  "$"
pct-encoded =
"%"  HEXDIG  HEXDIG
premrate =
premrate‑tag  "="  premrate‑value
premrate-tag =
"premium-rate"
premrate-value =
"information" /  "entertainment"
verstat =
verstat‑tag  "="  verstat‑value
verstat-tag =
"verstat"
verstat-value =
"TN‑Validation‑Passed" /  "TN‑Validation‑Failed" /  "No‑TN‑Validation" /  other‑value
other-value =
token
visual-separator =
"-" /  "." /  "(" /  ")"
Top
option-tag =
token
; see   IANA
; 100rel  → RFC 3262 – Section 8.1
; 199  → RFC 6228 – Section 11.2
; answermode  → RFC 5373 – Section 8.3
; early-session  → RFC 3959 – Section 9
; eventlist  → RFC 4662 – Section 8.1
; explicitsub  → RFC 7614 – Section 9.1
; from-change  → RFC 4916 – Section 6
; geolocation-http  → RFC 6442 – Section 8.3
; geolocation-sip  → RFC 6442 – Section 8.3
; gin  → RFC 6140 – Section 9.1
; gruu  → RFC 5627 – Section 11.3
; histinfo  → RFC 7044 – Section 14.1
; ice  → RFC 5768 – Section 7.1
; join  → RFC 3911 – Section 10.2
; multiple-refer  → RFC 5368 – Section 11
; norefersub  → RFC 4488 – Section 7
; nosub  → RFC 7614 – Section 9.2
; outbound  → RFC 5626 – Section 11.4
; path  → RFC 3327 – Section 7
; policy  → RFC 6794 – Section 6.4
; precondition  → RFC 3312 – Section 11
; pref  → RFC 3840 – Section 12.3
; privacy  → RFC 3323 – Section 7
; recipient-list-invite  → RFC 5366 – Section 8
; recipient-list-message  → RFC 5365 – Section 11
; recipient-list-subscribe  → RFC 5367 – Section 9.2
; record-aware  → RFC 7866 – Section 11.1.2
; replaces  → RFC 3891 – Section 9.2
; resource-priority  → RFC 4412 – Section 12.3
; sdp-anat  → RFC 4092 – Section 7
; sec-agree  → RFC 3329 – Section 6.5
; siprec  → RFC 7866 – Section 11.1.1
; tdialog  → RFC 4538 – Section 11.3
; timer  → RFC 4028 – Section 12.3
; uui  → RFC 7433 – Section 6.6
accept-param =
( "q"  EQUAL  qvalue ) /  generic‑param
qvalue =
( "0"  [ "."  0*3DIGIT ] ) /  ( "1"  [ "."  0*3( "0" ) ] )
generic-param =
token  [ EQUAL   gen‑value ]
gen-value =
token /  host /  quoted‑string
name-addr =
[ display‑name ]  LAQUOT  addr‑spec  RAQUOT
;  example:  Bob <sip:bob@biloxi.example.com>
display-name =
*( token  LWS ) /  quoted‑string
addr-spec =
SIP‑URI /  SIPS‑URI /  absoluteURI
callid =
word  [ "@"  word ]
delta-seconds =
1*DIGIT
Top
alphanum =
ALPHA /  DIGIT
LHEX =
DIGIT /  %x61‑66
; lowercase a‑f
LWS =
[ CRLF ]  1*WSP
; linear whitespace
SWS =
[ LWS ]
; sep whitespace
HCOLON =
*( SP /  HTAB )   ":"   SWS
separators =
"(" /  ")" /  "<" /  ">" /  "@" /  "," /  ";" /  ":" /  "\" /  DQUOTE /  "/" /  "[" /  "]" /  "?" /  "=" /  "{" /  "}" /  SP /  HTAB
STAR =
SWS  "*"  SWS
; asterisk
SLASH =
SWS  "/"  SWS
; slash
EQUAL =
SWS  "="  SWS
; equal
LPAREN =
SWS  "("  SWS
; left parenthesis
RPAREN =
SWS  ")"  SWS
; right parenthesis
LAQUOT =
SWS  "<"
; left angle quote
RAQUOT =
">"  SWS
; right angle quote
COMMA =
SWS  ","  SWS
; comma
SEMI =
SWS  ";"  SWS
; semicolon
COLON =
SWS  ":"  SWS
; colon
LDQUOT =
SWS  DQUOTE
; open double quotation mark
RDQUOT =
DQUOTE  SWS
; close double quotation mark
token =
1*( alphanum /  "-" /  "." /  "!" /  "%" /  "*" /  "_" /  "+" /  "`" /  "'" /  "~" )
quoted-string =
SWS   DQUOTE   *( qdtext /  quoted‑pair )   DQUOTE
qdtext =
LWS /  %x21 /  %x23‑5B /  %x5D‑7E /  UTF8‑NONASCII
quoted-pair =
"\"  ( %x00‑09 /  %x0B‑0C /  %x0E‑7F )
comment =
LPAREN   *( ctext /  quoted‑pair /  comment )   RPAREN
ctext =
%x21‑27 /  %x2A‑5B /  %x5D‑7E /  UTF8‑NONASCII /  LWS
word =
1*( alphanum /  "-" /  "." /  "!" /  "%" /  "*" /  "_" /  "+" /  "`" /  "'" /  "~" /  "(" /  ")" /  "<" /  ">" /  ":" /  "\" /  DQUOTE /  "/" /  "[" /  "]" /  "?" /  "{" /  "}" )
TEXT-UTF8-TRIM =
1*TEXT‑UTF8char   *( *LWS   TEXT‑UTF8char )
TEXT-UTF8char =
%x21‑7E /  UTF8‑NONASCII
UTF8-NONASCII =
%xC0-DF   1UTF8‑CONT /
%xE0-EF   2UTF8‑CONT /
%xF0-F7   3UTF8‑CONT /
%xF8-FB   4UTF8‑CONT /
%xFC-FD   5UTF8‑CONT
UTF8-CONT =
%x80-BF
escaped =
"%"   HEXDIG   HEXDIG
mark =
"-" /  "_" /  "." /  "!" /  "~" /  "*" /  "'" /  "(" /  ")"
reserved =
";" /  "/" /  "?" /  ":" /  "@" /  "&" /  "=" /  "+" /  "$" /  ","
unreserved =
alphanum /  mark
Top
OCTET =
%x00-FF
; 8 bits of data
CHAR =
%x01-7F
; any 7-bit US-ASCII character,
; excluding NUL
VCHAR =
%x21-7E
; visible (printing) characters
ALPHA =
%x41‑5A /  %x61‑7A
; A‑Z  /  a‑z
DIGIT =
%x30‑39
; 0-9
CTL =
%x00‑1F /  %x7F
; any US-ASCII control character:
; (octets 0 - 31) and DEL (127)
HTAB =
%x09
; horizontal tab
LF =
%x0A
; linefeed
CR =
%x0D
; carriage return
SP =
%x20
; space
DQUOTE =
%x22
; " (Double Quote)
BIT =
"0" /  "1"
HEXDIG =
DIGIT /  "A" /  "B" /  "C" /  "D" /  "E" /  "F"
; Note: according to the 'char-val' rule,
; letters (A-F) are case insensitive
CRLF =
CR  LF
; Internet standard newline
WSP =
SP /  HTAB
; white space
LWSP =
*( WSP /  CRLF  WSP )
; linear white space (past newline)

Top