
Session Initiation Protocol (SIP) Parameters 

(last updated 2006-09-12)

Registries included below:
- Header Fields
- Option Tags
- Warning Codes (warn-codes)
- Methods and Response Codes
- Reason Protocols
- Security Mechanism Names
- Compression Schemes
- SIP/SIPS URI Parameters
- Header Field Parameters and Parameter Values
- URI purposes
- Identity-Info Parameters
- Identity-Info Algorithm Parameter Values

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-Contact       a        [RFC3841]
  Accept-Encoding               [RFC3261]
  Accept-Language               [RFC3261]
  Accept-Resource Priority      [RFC-ietf-sip-resource-priority-10.txt]
  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)
  History-Info                  [RFC4244]
  Identity             y        [RFC4474] 
  Identity-Info        n        [RFC4474]
  In-Reply-To                   [RFC3261]
  Join                          [RFC3911]
  Max-Forwards                  [RFC3261]
  MIME-Version                  [RFC3261]
  Min-Expires                   [RFC3261]
  Min-SE                        [RFC4028] 
  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-DCS-Trace-Party-ID          [RFC3603]
  P-DCS-OSPS                    [RFC3603]
  P-DCS-Billing-Info            [RFC3603]
  P-DCS-LAES                    [RFC3603]
  P-DCS-Redirect                [RFC3603]
  P-Media-Authorization         [RFC3313]
  P-Preferred-Identity          [RFC3325]
  P-User-Database               [RFC-camarillo-sipping-user-database-02.txt]
  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]
  Refer-Sub                     [RFC-ietf-sip-refer-with-norefersub-04.txt]
  Refer-To               r      [RFC3515]
  Referred-By            b      [RFC3892]
  Reject-Contact         j      [RFC3841]
  Replaces                      [RFC3891]
  Reply-To                      [RFC3261]
  Request-Disposition    d      [RFC3841]
  Require                       [RFC3261]
  Resource-Priority             [RFC-ietf-sip-resource-priority-10.txt]
  Response-Key (Deprecated)     [RFC3261]
  Retry-After                   [RFC3261]
  Route                         [RFC3261]
  RSeq                          [RFC3262]
  Security-Client               [RFC3329]
  Security-Server               [RFC3329]
  Security-Verify               [RFC3329]
  Server                        [RFC3261]
  Service-Route                 [RFC3608]
  Session-Expires      x        [RFC4028]
  SIP-ETag                      [RFC3903]
  SIP-If-Match                  [RFC3903]
  Subject              s        [RFC3261]
  Subscription-State            [RFC3265]
  Supported            k        [RFC3261]
  Target-Dialog                 [RFC4538]
  Timestamp                     [RFC3261]
  To                   t        [RFC3261]
  Unsupported                   [RFC3261]
  User-Agent                    [RFC3261]
  Via                  v        [RFC3261]
  Warning                       [RFC3261]
  WWW-Authenticate              [RFC3261]


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

  Protocol value  Protocol Cause                    Reference
  --------------  ------------------------------    ---------
  SIP             Status code                       [RFC3261]  
  Q.850           Cause value in decimal        [ITU-T Q.850]
                  representation            
  Preemption      Cause value in decimal*           [RFC4411]

* see the separate "Preemption" Registry for default reason-text strings
http://www.iana.org/assignments/preemption-namespace

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.

early-session   A UA adding the early-session option tag     [RFC3959]
                to a message indicates that it understands
                the early-session content disposition.

eventlist       Extension to allow subscriptions to lists    [RFC4662]
                of resources

histinfo        When used with the Supported header,         [RFC-ietf-sip-history-info-06.txt]
                this option tag indicates support 
                for the History Information to be  
                captured for requests and returned in 
                subsequent responses. This tag is not 
                used in a Proxy-Require or Require  
                header field since support of  
                History-Info is optional.

join            Support for the SIP Join Header              [RFC3911]

norefersub      This option tag specifies a User Agent       [RFC-ietf-sip-refer-with-norefersub-04.txt]
                ability of accepting a REFER request without 
                establishing an implicit subscription 
                (compared to the default case defined in 
                RFC3515).
 
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. 

pref            This option tag is used to ensure that a    [RFC3840]
                server understands the callee capabilities 
                parameters used in the request.

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.     

replaces        This option tag indicates support for the    [RFC3891]
                SIP Replaces header.

resource-priority  Indicates or requests support for the     [RFC-ietf-sip-resource-priority-10.txt]
                   resource priority mechanism.

sdp-anat        The option-tag sdp-anat is defined for use   [RFC4092] 
                in the Require and Supported SIP [RFC3261] 
                header fields. SIP user agents that place this
                option-tag in a Supported header field understand 
                the ANAT semantics as defined in [RFC4091].


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.

tdialog         This option tag is used to identify the target  [RFC4538]
                dialog header field extension.  When used in a Require 
                header field, it implies that the recipient needs to 
                support the Target-Dialog header field.  When used in 
                a Supported header field, it implies that the sender 
                of the message supports it.

timer           This option tag is for support of the        [RFC4028]
                session timer extension.  Inclusion in a Supported 
                header field in a request or response indicates that 
                the UA is capable of performing refreshes according 
                to that specification.  Inclusion in a Require header 
                in a request means that the UAS must understand the 
                session timer extension to process the request.  
                Inclusion in a Require header field in a response 
                indicates that the UAC must look for the 
                Session-Expires header field in the response, and 
                process accordingly.

 

 
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]
  MESSAGE                  [RFC3428]
  NOTIFY                   [RFC3265]
  OPTIONS                  [RFC3261]
  PRACK                    [RFC3262]
  PUBLISH                  [RFC3903]
  REFER                    [RFC3515]
  REGISTER                 [RFC3261]
  SUBSCRIBE                [RFC3265]
  UPDATE                   [RFC3311]

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
    412 Conditional Request Failed            [RFC3903]
    413 Request Entity Too Large
    414 Request-URI Too Long
    415 Unsupported Media Type
    416 Unsupported URI Scheme
    417 Unknown Resource-Priority             [RFC-ietf-sip-resource-priority-10.txt]
    420 Bad Extension
    421 Extension Required
    422 Session Interval Too Small            [RFC4028]
    423 Interval Too Brief
    428 Use Identity Header                   [RFC4474]
    429 Provide Referrer Identity             [RFC3892]
    436 Bad Identity-Info                     [RFC4474]
    437 Unsupported Certificate               [RFC4474]
    438 Invalid Identity Header               [RFC4474]
    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]

SIP/SIPS URI Parameters - per [RFC3969]
(New registrations are via Specification Required)

Parameter Name     Predefined Values     Reference
--------------     -----------------     ---------
cause              Yes                   [RFC-jennings-sip-voicemail-uri-06.txt]
comp               Yes                   [RFC3486]
content-type       No                    [RFC4240] 
delay              No                    [RFC4240] 
duration           No                    [RFC4240] 
locale             No                    [RFC4240]                 
lr                 No                    [RFC3261]
maddr              No                    [RFC3261]
method             Yes                   [RFC3261]
param[n]           No                    [RFC4240] 
play               No                    [RFC4240] 
repeat             No                    [RFC4240] 
target             No                    [RFC-jennings-sip-voicemail-uri-06.txt]
transport          Yes                   [RFC3261]
ttl                No                    [RFC3261]
user               Yes                   [RFC3261]
voicexml           No                    [RFC4240] 


Header Field Parameters and Parameter Values - per [RFC3968]
(New registrations must be defined in a RFC.  
A standards-track RFC is NOT required)

                                               Predefined
Header Field                  Parameter Name     Values     Reference
----------------------------  ---------------   ---------   ---------                                     
Accept                        q                    No       [RFC3261]
Accept-Encoding               q                    No       [RFC3261]
Accept-Language               q                    No       [RFC3261]
Authorization                 algorithm           Yes       [RFC3261] [[RFC3310]]
Authorization                 auts                 No       [RFC3310]
Authorization                 cnonce               No       [RFC3261]
Authorization                 nc                   No       [RFC3261]
Authorization                 nonce                No       [RFC3261]
Authorization                 opaque               No       [RFC3261]
Authorization                 qop                 Yes       [RFC3261]
Authorization                 realm                No       [RFC3261]
Authorization                 response             No       [RFC3261]
Authorization                 uri                  No       [RFC3261]
Authorization                 username             No       [RFC3261]
Authentication-Info           cnonce               No       [RFC3261]
Authentication-Info           nc                   No       [RFC3261]
Authentication-Info           nextnonce            No       [RFC3261]
Authentication-Info           qop                 Yes       [RFC3261]
Authentication-Info           rspauth              No       [RFC3261]
Call-Info                     purpose             Yes       [RFC3261]
Contact                       expires              No       [RFC3261]
Contact                       q                    No       [RFC3261]
Content-Disposition           handling            Yes       [RFC3261]
Event                         id                   No       [RFC3265]
From                          tag                  No       [RFC3261]
P-Access-Network-Info         cgi-3gpp             No       [RFC3455]
P-Access-Network-Info         utran-cell-id-3gpp   No       [RFC3455]
P-Charging-Function-Addresses ccf                  No       [RFC3455]
P-Charging-Function-Addresses ecf                  No       [RFC3455]
P-Charging-Vector             icid-value           No       [RFC3455]
P-Charging-Vector             icid-generated-at    No       [RFC3455]
P-Charging-Vector             orig-ioi             No       [RFC3455]
P-Charging-Vector             term-ioi             No       [RFC3455]
P-DCS-Billing-Info            called               No       [RFC3603]
P-DCS-Billing-Info            calling              No       [RFC3603]
P-DCS-Billing-Info            charge               No       [RFC3603]
P-DCS-Billing-Info            locroute             No       [RFC3603]
P-DCS-Billing-Info            rksgroup             No       [RFC3603]
P-DCS-Billing-Info            routing              No       [RFC3603]
P-DCS-LAES                    content              No       [RFC3603]
P-DCS-LAES                    key                  No       [RFC3603]
P-DCS-Redirect                count                No       [RFC3603]
P-DCS-Redirect                redirector-uri       No       [RFC3603]
Proxy-Authenticate            algorithm           Yes       [RFC3261] [[RFC 3310]]
Proxy-Authenticate            domain               No       [RFC3261]
Proxy-Authenticate            nonce                No       [RFC3261]
Proxy-Authenticate            opaque               No       [RFC3261]
Proxy-Authenticate            qop                 Yes       [RFC3261]
Proxy-Authenticate            realm                No       [RFC3261]
Proxy-Authenticate            stale               Yes       [RFC3261]
Proxy-Authorization           algorithm           Yes       [RFC3261] [[RFC 3310]]
Proxy-Authorization           auts                 No       [RFC3310]
Proxy-Authorization           cnonce               No       [RFC3261]
Proxy-Authorization           nc                   No       [RFC3261]
Proxy-Authorization           nonce                No       [RFC3261]
Proxy-Authorization           opaque               No       [RFC3261]
Proxy-Authorization           qop                 Yes       [RFC3261]
Proxy-Authorization           realm                No       [RFC3261]
Proxy-Authorization           response             No       [RFC3261]
Proxy-Authorization           uri                  No       [RFC3261]
Proxy-Authorization           username             No       [RFC3261]
Reason                        cause               Yes       [RFC3326]
Reason                        text                 No       [RFC3326]
Retry-After                   duration             No       [RFC3261]
Security-Client               alg                 Yes       [RFC3329]
Security-Client               ealg                Yes       [RFC3329]
Security-Client               d-alg               Yes       [RFC3329]
Security-Client               d-qop               Yes       [RFC3329]
Security-Client               d-ver                No       [RFC3329]
Security-Client               mod                 Yes       [RFC3329]
Security-Client               port1                No       [RFC3329]
Security-Client               port2                No       [RFC3329]
Security-Client               prot                Yes       [RFC3329]
Security-Client               q                    No       [RFC3329]
Security-Client               spi                  No       [RFC3329]
Security-Server               alg                 Yes       [RFC3329]
Security-Server               ealg                Yes       [RFC3329]
Security-Server               d-alg               Yes       [RFC3329]
Security-Server               d-qop               Yes       [RFC3329]
Security-Server               d-ver                No       [RFC3329]
Security-Server               mod                 Yes       [RFC3329]
Security-Server               port1                No       [RFC3329]
Security-Server               port2                No       [RFC3329]
Security-Server               prot                Yes       [RFC3329]
Security-Server               q                    No       [RFC3329]
Security-Server               spi                  No       [RFC3329]
Security-Verify               alg                 Yes       [RFC3329]
Security-Verify               ealg                Yes       [RFC3329]
Security-Verify               d-alg               Yes       [RFC3329]
Security-Verify               d-qop               Yes       [RFC3329]
Security-Verify               d-ver                No       [RFC3329]
Security-Verify               mod                 Yes       [RFC3329]
Security-Verify               port1                No       [RFC3329]
Security-Verify               port2                No       [RFC3329]
Security-Verify               prot                Yes       [RFC3329]
Security-Verify               q                    No       [RFC3329]
Security-Verify               spi                  No       [RFC3329]
Subscription-State            expires              No       [RFC3265]
Subscription-State            reason              Yes       [RFC3265]
Subscription-State            retry-after          No       [RFC3265]
Target-Dialog                 local-tag            No       [RFC4538] 
Target-Dialog                 remote-tag           No       [RFC4538]
To                            tag                  No       [RFC3261]
Via                           branch               No       [RFC3261]
Via                           comp                Yes       [RFC3486]
Via                           maddr                No       [RFC3261]
Via                           received             No       [RFC3261]
Via                           rport                No       [RFC3581]
Via                           ttl                  No       [RFC3261]
WWW-Authenticate              algorithm           Yes       [RFC3261] [[RFC 3310]]
WWW-Authenticate              domain              Yes       [RFC3261]
WWW-Authenticate              nonce                No       [RFC3261]
WWW-Authenticate              opaque               No       [RFC3261]
WWW-Authenticate              qop                 Yes       [RFC3261]
WWW-Authenticate              realm                No       [RFC3261]
WWW-Authenticate              stale               Yes       [RFC3261]


URI Purposes - per [RFC4575]
Registration Rules: Specification Required 
 
Value            Description                                 Reference
---------------  ------------------------------------------  ----------
participation    The URI can be used to join the conference  [RFC4575]
streaming        The URI can be used to access the streamed  [RFC4575]
                 conference data
event            The URI can be used to subscribe to the     [RFC4575]
                 conference event package
recording        The URI can be used to access the recorded  [RFC4575]
                 conference data
web-page         The URI can be used to access a  web page   [RFC4575]
                 that contains additional information of 
                 the conference

Resource-Priority Namespaces - per [RFC-ietf-sip-resource-priority-10.txt]
Registration Procedures: RFC publication
                      Intended       New warn-    New resp.
Namespace  Levels     Algorithm      code         code      Reference
---------  ------  ----------------  ---------    --------- ---------
   dsn       5        preemption        no           no     [RFC-ietf-sip-resource-priority-10.txt]
   drsn      6        preemption        no           no     [RFC-ietf-sip-resource-priority-10.txt]
   q735      5        preemption        no           no     [RFC-ietf-sip-resource-priority-10.txt]
   ets       5        queue             no           no     [RFC-ietf-sip-resource-priority-10.txt]
   wps       5        queue             no           no     [RFC-ietf-sip-resource-priority-10.txt]

Legend
------
Namespace      = the unique string identifying the namespace
Levels         = the number of priority-values within the namespace
Algorithm      = Intended operational behavior of SIP elements
                 implementing this namespace
New Warn code  = New Warning Codes (warn-codes) introduced by this namespace
New Resp. code = New SIP response codes introduced by this namespace
Reference      = IETF document reference for this namespace


Resource-Priority Priority-values - per [RFC-ietf-sip-resource-priority-10.txt]
Registration Procedures: RFC publication

Namespace: drsn
Reference: [RFC-ietf-sip-resource-priority-10.txt]
Priority-Values (least to greatest): "routine", "priority",
   "immediate", "flash", "flash-override", "flash-override-override"

Namespace: dsn
Reference: [RFC-ietf-sip-resource-priority-10.txt]
Priority-Values (least to greatest): "routine", "priority",
   "immediate", "flash", "flash-override"

Namespace: q735
Reference: [RFC-ietf-sip-resource-priority-10.txt]
Priority values (least to greatest): "4", "3", "2", "1", "0"

Namespace: ets
Reference: [RFC-ietf-sip-resource-priority-10.txt]
Priority values (least to greatest): "4", "3", "2", "1", "0"

Namespace: wps
Reference: [RFC-ietf-sip-resource-priority-10.txt]
Priority values (least to greatest): "4", "3", "2", "1", "0"


Identity-Info Parameters - per [RFC4474]
Registration Procedures: Standards Track RFC

Parameter Name          Reference
----------------------  ---------
alg                     [RFC4474]


Identity-Info Algorithm Parameter Values - per [RFC4474]
Registration Procedures: Standards Track RFC

'alg' Parameter Name    Reference
----------------------  ---------
rsa-sha1                [RFC4474]


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.

[RFC3310]  A. Niemi, J. Arkko, and V. Torvinen, "Hypertext Transfer Protocol 
           (HTTP) Digest Authentication Using Authentication and Key 
           Agreement (AKA), RFC 3310, September 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.

[RFC3581]  J. Rosenberg and H. Schulzrinne, "An Extension to the Session 
           Initiation Protocol (SIP) for Symmetric Response Routing",
           RFC 3581, August 2003.

[RFC3603]  W. Marshall, Ed. and F. Andreasen, Ed., "Private Session 
           Initiation Protocol (SIP) Proxy-to-Proxy Extensions for 
           Supporting the PacketCable Distributed Call Signaling 
           Architecture", RFC 3603, October 2003.

[RFC3608]  D. Willis and B. Hoeneisen, "Session Initiation Protocol 
           Extension Header Field for Service Route Discovery During 
           Registration", RFC 3608, October 2003.

[RFC3840]  J. Rosenberg, H. Schulzrinne, and P. Kyzivat, "Indicating User 
           Agent Capabilities in the Session Initiation Protocol", 
           RFC 3840, August 2004.

[RFC3841]  J. Rosenberg, H. Schulzrinne, and P. Kyzivat, "Caller Preferences 
           for the Session Initiation Protocol (SIP)", RFC 3841, August 2004.

[RFC3891]  R. Mahy, B. Biggs, and R. Dean, "The Session Inititation Protocol 
           (SIP) "Replaces" Header", RFC 3891, September 2004.

[RFC3892]  R. Sparks, "The SIP Referred-By Mechanism", RFC 3892, September 2004.

[RFC3903]  A. Niemi, Ed., "An Event State Publication Extension to the Session 
           Initiation", RFC 3903, October 2004.

[RFC3911]  R. Mahy and D. Petrie, "The Session Inititation Protocol (SIP) 
           'Join' Header", RFC 3911, October 2004.

[RFC3959]  G. Camarillo, "The Early Session Disposition Type for the 
           Session Initiation Protocol (SIP)", RFC 3959, December 2004.

[RFC3968]  G. Camarillo, "The Internet Assigned Number Authority (IANA) 
           Header Field Parameter Registry for the Session Initiation 
           Protocol (SIP)", RFC 3968, December 2004.

[RFC3969]  G. Camarillo, "The Internet Assigned Number Authority (IANA) 
           Universal Resource Identifier (URI) Parameter Registry for the 
           Session", RFC 3969, December 2004.

[RFC4028]  S. Donovan and J. Rosenberg, "Session Timers in the Session 
           Initiation Protocol (SIP)", RFC 4028, April 2005.

[RFC4091]  G. Camarillo and J. Rosenberg, "The Alternative Network Address 
           Types Semantics (ANAT) for the Session Description Protocol (SDP) 
           Grouping Framework", RFC 4091, June 2005.

[RFC4092]  G. Camarillo and J. Rosenberg, "Usage of the Session Description 
           Protocol (SDP) Alternative Network Address Types (ANAT) Semantics 
           in the Session Initiation Protocol", RFC 4092, June 2005.            

[RFC4240]  E. Burger, Ed., J. Van Dyke, and A. Spitzer, "Basic Network Media 
           Services with SIP", RFC 4240, December 2005.

[RFC4244]  M. Barnes, Ed., "An Extension to the Session Initiation Protocol 
           for Request History Information", RFC 4244, November 2005.

[RFC4575]  J. Rosenberg, H. Schulzrinne and O. Levin, "A Session Initiation 
           Protocol (SIP) Event Package for Conference State", RFC 4575,
           August 2006.

[RFC-ietf-sip-resource-priority-10.txt]
           H. Schulzrinne and J. Polk, "Communications Resource Priority for 
           the Session Initiation Protocol (SIP)", RFC XXXX, Month Year.

[RFC4411]   J. M. Polk, "Extending the Session Initiation Protocol Reason Header 
            for Preemption Events", RFC 4411, February 2006.

[RFC4474]   J. Peterson and  C. Jennings, "Enhancements for Authenticated Identity 
            Management in the Session Initiation Protocol (SIP)", RFC 4474, August 2006.

[RFC-jennings-sip-voicemail-uri-06.txt]
            C. Jennings, F. Audet and J. Elwell, "Session Initiation Protocol (SIP) 
            URIs for Applications such as Voicemail and Interactive Voice Response (IVR)",
            RFC XXXX, Month Year.

[RFC-camarillo-sipping-user-database-02.txt]
            G. Camarillo and G. Blanco, "The Session Initiation Protocol (SIP) 
            P-User-Database Private-Header (P-Header)", RFC XXXX, Month Year.

[RFC4538]   J. Rosenberg, "Request Authorization through Dialog Identification in the 
            Session Initiation Protocol (SIP)", RFC 4538, June 2006.

[RFC4662]  J. Rosenberg and A. B. Roach, "A Session Initiation Protocol (SIP) Event 
           Notification Extension for Resource Lists", RFC 4662, August 2006.
		   
[RFC-ietf-sip-refer-with-norefersub-04.txt]
            O. Levin, "Suppression of Session Initiation Protocol REFER Method Implicit",
            RFC XXXX, Month Year.

(registry created 2002)

[]
