
Session Initiation Protocol (SIP) Parameters 
-Header Fields
-Option Tags
-Warning Codes (warn-codes)
-Methods and Response Codes
-Reason Protocols
-Security Mechanism Names
-Compression Schemes

(last updated 2003-04-28)

For registration procedures, please see [RFC3427]

Header Fields - per [RFC3261] Section 27.3
-------------
The table below lists the header fields currently defined for the
Session Initiation Protocol (SIP) [RFC3261]. Some headers have
single-letter compact forms (Section 7.3 of RFC 3261). Header field
names are case-insensitive.

  Header Name        compact    Reference
  -----------------  -------    ---------
  Accept                        [RFC3261]
  Accept-Encoding               [RFC3261]
  Accept-Language               [RFC3261]
  Alert-Info                    [RFC3261]
  Allow                         [RFC3261]
  Allow-Events         u        [RFC3265]
  Authentication-Info           [RFC3261]
  Authorization                 [RFC3261]
  Call-ID              i        [RFC3261]
  Call-Info                     [RFC3261]
  Contact              m        [RFC3261]
  Content-Disposition           [RFC3261]
  Content-Encoding     e        [RFC3261]
  Content-Language              [RFC3261]
  Content-Length       l        [RFC3261]
  Content-Type         c        [RFC3261]
  CSeq                          [RFC3261]
  Date                          [RFC3261]
  Encryption (Deprecated)       [RFC3261]
  Error-Info                    [RFC3261]
  Event                o        [RFC3265]
  Expires                       [RFC3261]
  From                 f        [RFC3261]
  Hide                          [RFC3261] (deprecated)
  In-Reply-To                   [RFC3261]
  Max-Forwards                  [RFC3261]
  MIME-Version                  [RFC3261]
  Min-Expires                   [RFC3261]
  Organization                  [RFC3261]
  P-Access-Network-Info         [RFC3455]
  P-Asserted-Identity           [RFC3325]
  P-Associated-URI              [RFC3455]
  P-Called-Party-ID             [RFC3455]
  P-Charging-Function-Addresses [RFC3455]
  P-Charging-Vector             [RFC3455]
  P-Media-Authorization         [RFC3313]
  P-Preferred-Identity          [RFC3325]
  P-Visited-Network-ID          [RFC3455]
  Path                          [RFC3327]
  Priority                      [RFC3261]
  Privacy                       [RFC3323]
  Proxy-Authenticate            [RFC3261]
  Proxy-Authorization           [RFC3261]
  Proxy-Require                 [RFC3261]
  RAck                          [RFC3262]
  Reason                        [RFC3326]
  Record-Route                  [RFC3261]
  Reply-To                      [RFC3261]
  Require                       [RFC3261]
  Response-Key (Deprecated)     [RFC3261]
  Retry-After                   [RFC3261]
  Route                         [RFC3261]
  RSeq                          [RFC3262]
  Security-Client               [RFC3329]
  Security-Server               [RFC3329]
  Security-Verify               [RFC3329]
  Server                        [RFC3261]
  Subject              s        [RFC3261]
  Subscription-State            [RFC3265]
  Supported            k        [RFC3261]
  Timestamp                     [RFC3261]
  To                   t        [RFC3261]
  Unsupported                   [RFC3261]
  User-Agent                    [RFC3261]
  Via                  v        [RFC3261]
  Warning                       [RFC3261]
  WWW-Authenticate              [RFC3261]
  Refer-To             r        [RFC3515]

Reason Protocols - per [RFC3326] 
----------------

  Protocol value  Protocol Cause                    Reference
  --------------  ------------------------------    ---------
  SIP             Status code                       [RFC3261]  
  Q.850           Cause value in decimal        [ITU-T Q.850]
                  representation            


Option Tags - per [RFC3261] Section 27.1
-----------
Option tags are used in header fields such as Require, Supported,
Proxy-Require, and Unsupported in support of SIP compatibility
mechanisms for extensions. The option tag itself is a string that 
is associated with a particular SIP option (that is, an extension). 
It identifies the option to SIP endpoints.

  Name          Description                                 Reference
  -----------   ------------------------------------------  ---------
  100rel        This option tag is for reliability of       [RFC3262]
                provisional responses. When present in a 
                Supported header, it indicates that the UA 
                can send or receive reliable provisional
                responses. When present in a Require header 
                in a request it indicates that the UAS MUST 
                send all provisional responses reliably. 
                When present in a Require header in a
                reliable provisional response, it indicates 
                that the response is to be sent reliably.
 
  path          A SIP UA that supports the Path extension    [RFC3327]
                header field includes this option tag as a 
                header field value in a Supported header 
                field in all requests generated by that UA. 
                Intermediate proxies may use the presence 
                of this option tag in a REGISTER request to
                determine whether to offer Path service for 
                for that request. If an intermediate proxy 
                requires that the registrar support Path for 
                a request, then it includes this option tag 
                as a header field value in a Requires 
                header field in that request.

  precondition  An offerer MUST include this tag in  the     [RFC3312] 
                Require header field if the offer contains 
                one or more "mandatory" strength-tags.  If 
                all the strength-tags in the description are
                "optional" or "none" the offerer MUST include 
                this tag either in a Supported header field or 
                in a Require header field. 

  privacy       This option tag indicates support for the    [RFC3323]
                Privacy mechanism. When used in the 
                Proxy-Require header, it indicates that proxy 
                servers do not forward the request unless they 
                can provide the requested privacy service. 
                This tag is not used in the Require or 
                Supported headers. Proxies remove this option
                tag before forwarding the request if the desired 
                privacy function has been performed.     

  sec-agree     This option tag indicates support for the    [RFC3329]
                Security Agreement mechanism. When used in the 
                Require, or Proxy-Require headers, it indicates that 
                proxy servers are required to use the Security 
                Agreement mechanism.  When used in the Supported 
                header, it indicates that the User Agent Client 
                supports the Security Agreement mechanism. When used 
                in the Require header in the 494 (Security Agreement 
                Required) or 421 (Extension Required) responses, it 
                indicates that the User Agent Client must use the 
                Security Agreement Mechanism.


Warning Codes (warn-codes) - per [RFC3261] Section 27.2
--------------------------
Warning codes provide information supplemental to the status code in
SIP response messages when the failure of the transaction results
from a Session Description Protocol (SDP) (RFC 2327 [1]) problem.

  Code  Description                                          Reference
  ----  ---------------------------------------------------  ---------
  300   Incompatible network protocol: One or more network   [RFC3261]
        protocols contained in the session description are 
        not available.

  301   Incompatible network address formats: One or more    [RFC3261] 
        network address formats contained in the session 
        description are not available.

  302   Incompatible transport protocol: One or more         [RFC3261]
        transport protocols described in the session 
        description are not available.

  303   Incompatible bandwidth units: One or more bandwidth  [RFC3261]
        measurement units contained in the session 
        description were not understood.

  304   Media type not available: One or more media types    [RFC3261]
        contained in the session description are not 
        available.

  305   Incompatible media format: One or more media formats [RFC3261]
        contained in the session description are not 
        available.

  306   Attribute not understood: One or more of the media   [RFC3261]
        attributes in the session description are not 
        supported.

  307   Session description parameter not understood: A      [RFC3261]
        parameter other than those listed above was not 
        understood.

  330   Multicast not available: The site where the user is  [RFC3261]
        located does not support multicast.

  331   Unicast not available: The site where the user is    [RFC3261]
        located does not support unicast communication 
        (usually due to the presence of a firewall).

  370   Insufficient bandwidth: The bandwidth specified in   [RFC3261]
        the session description or defined by the media 
        exceeds that known to be available.

  399   Miscellaneous warning: The warning text can include  [RFC3261]
        arbitrary information to be presented to a human user 
        or logged. A system receiving this warning MUST NOT 
        take any automated action.  


Methods and Response Codes - per [RFC3261] Section 27.4
--------------------------

  Methods                  Reference
  -------                  ---------
  ACK                      [RFC3261]
  BYE                      [RFC3261]
  CANCEL                   [RFC3261]
  INFO                     [RFC2976]
  INVITE                   [RFC3261]
  NOTIFY                   [RFC3265]
  OPTIONS                  [RFC3261]
  PRACK                    [RFC3262]
  REGISTER                 [RFC3261]
  SUBSCRIBE                [RFC3265]
  UPDATE                   [RFC3311]
  MESSAGE                  [RFC3428]
  REFER                    [RFC3515]

Response Codes
--------------
All response codes below are defined by [RFC3261] unless
otherwise noted.

  Response Code                               Reference
  -------------                               ---------
  Provisional 1xx
    100 Trying
    180 Ringing
    181 Call Is Being Forwarded
    182 Queued
    183 Session Progress

  Successful 2xx
    200 OK
    202 Accepted                              [RFC3265]

  Redirection 3xx
    300 Multiple Choices
    301 Moved Permanently
    302 Moved Temporarily
    305 Use Proxy
    380 Alternative Service

  Request Failure 4xx
    400 Bad Request
    401 Unauthorized
    402 Payment Required
    403 Forbidden
    404 Not Found
    405 Method Not Allowed
    406 Not Acceptable
    407 Proxy Authentication Required 
    408 Request Timeout
    410 Gone
    413 Request Entity Too Large
    414 Request-URI Too Long
    415 Unsupported Media Type
    416 Unsupported URI Scheme
    420 Bad Extension
    421 Extension Required
    423 Interval Too Brief
    480 Temporarily Unavailable
    481 Call/Transaction Does Not Exist
    482 Loop Detected
    483 Too Many Hops
    484 Address Incomplete
    485 Ambiguous
    486 Busy Here
    487 Request Terminated
    488 Not Acceptable Here
    489 Bad Event                             [RFC3265]
    491 Request Pending 
    493 Undecipherable
    494 Security Agreement Required           [RFC3329]
    
  Server Failure 5xx
    500 Server Internal Error
    501 Not Implemented
    502 Bad Gateway
    503 Service Unavailable
    504 Server Time-out
    505 Version Not Supported
    513 Message Too Large
    580 Precondition Failure                  [RFC3312] 
  
  Global Failures 6xx
    600 Busy Everywhere
    603 Decline
    604 Does Not Exist Anywhere
    606 Not Acceptable

Security Mechanism Names - per [RFC3329] Section 6
---------------

  Mechanism Name                         Reference
  --------------                         ---------
  digest                                 [RFC3329]
  tls                                    [RFC3329]
  ipsec-ike                              [RFC3329]
  ipsec-man                              [RFC3329]
  ipsec-3gpp                             [RFC3329]

Compression Schemes - per [RFC3486] Section 11

   Compression Scheme       Token        Reference
   ---------------------    ---------    ---------
   Signaling Compression    sigcomp      [RFC3486]


References
----------
[RFC2976]  S. Donovan, "The SIP INFO Method", RFC 2976, October 2000.

[RFC3261]  J. Rosenberg, H. Schulzrinne, G. Camarillo, A. Johnston, 
           J. Peterson, R. Sparks, M. Handley, and E. Schooler,
           "SIP: Session Initiation Protocol", RFC 3261, June 2002.

[RFC3262]  J. Rosenberg and H. Schulzrinne, "Reliability of Provisional 
           Responses in SIP", RFC 3262, June 2002.

[RFC3265]  A. Roach, "SIP-Specific Event Notification", RFC 3265,
           June 2002.

[RFC3311]  J. Rosenberg, "The Session Initiation Protocol UPDATE Method", 
           RFC 3311, September 2002.

[RFC3312]  G. Camarillo, W. Marshall, and J. Rosenberg, "Integration of 
           Resource Management and SIP", RFC 3312, September 2002.

[RFC3313]  W. Marshall, F. Andreasen, D. Evans, and B. Beser, "SIP Extensions 
           for Media Authorization", RFC 3313, September 2002.	

[RFC3323]  J. Peterson, "A Privacy Mechanism for the Session Initiation 
           Protocol (SIP), RFC 3323, November 2002.	   

[RFC3325]  C. Jennings, J. Peterson, M. Watson, "Private Extensions to the 
           Session Initiation Protocol (SIP) for Asserted Identity within 
           Trusted Networks", RFC 3325, November 2002.

[RFC3326]  H. Schulzrinne, D. Oran, and G. Camarillo, "The Reason Header 
           Field for the Session Initiation Protocol", RFC 3326, November 2002.

[RFC3327]  D. Willis, B. Hoeneisen, "Session Initiation Protocol Extension 
           Header Field for Registering Non-Adjacent Contacts", RFC 3327,
           November 2002.

[RFC3329]  J. Arkko, V. Torvinen, G. Camarillo, A. Niemi, and T. Haukka,
           "Security Mechanism Agreement for the Session Initiation 
           Protocol (SIP)", RFC 3329, January 2003.

[RFC3427]  A. Mankin, S. Bradner, R. Mahy, D. Willis, J. Ott, and B. Rosen,
           "Change Process for the Session Initiation Protocol (SIP)", 
           RFC 3427, November 2002.		   

[RFC3428]  B. Campbell, J. Rosenberg, H. Schulzrinne, C. Huitema, and 
           D. Gurle, "Session Initiation Protocol Extension for Instant 
           Messaging", RFC 3428, November 2002.

[RFC3455]  M. Garcia-Martin, E. Henrikson, and D. Mills, "Private Header 
           (P-Header) Extensions to the Session Initiation Protocol (SIP) 
           for the 3rd-Generation Partnership Project (3GPP)", RFC 3455,
           January 2003.

[RFC3486]  G. Camarillo, "Compressing the Session Initiation Protocol",
           RFC 3486, February 2003.

[RFC3515]  R. Sparks, "The SIP Refer Method", RFC 3515, April 2003.

(created 2002)

[]
