SIP Headers


Detailed Description

SIP headers and other SIP message elements.

For each SIP header recognized by the SIP module, there is a header structure containing the parsed value. The header structure name is generated from the header name by lowercasing the name, replacing the non-alphanumeric characters (usually just minus "-") with underscore "_" characters, and then adding prefix sip_ and suffix _t. For instance, the contents of header "MIME-Version" is stored in a structure called sip_mime_version_t.


Modules

 SIP Header X - Conventions
 For a SIP header X, there are types, functions, macros and global data declared in <sofia-sip/sip_protos.h> and <sofia-sip/sip_hclass.h> as follows:
 Request Line
 The request line is first line in a SIP request message.
 Status Line
 The status line is first line in a response message.
 Message Body
 The payload structure contains the optional message body.
 Separator Line
 An empty line separates message headers from the message body (payload).
 Unknown Headers
 The unknown headers are handled with sip_unknown_t structure.
 Erroneous Headers
 The erroneous headers are stored in sip_error_t structure.
 Call-ID Header
 The Call-ID header uniquely identifies a particular invitation or all registrations of a particular client.
 CSeq Header
 The CSeq header (command sequence) uniquely identifies transactions within a dialog.
 Contact Header
 The Contact header contain a list of URLs used to redirect future requests.
 Content-Length Header
 The Content-Length header indicates the size of the message-body in decimal number of octets.
 Date Header
 The Date header field reflects the time when the request or response was first sent.
 Expires Header
 The Expires header field gives the date and time after which the message content expires.
 From Header
 The From header indicates the initiator of the request.
 Max-Forwards Header
 The Max-Forwards header is used to limit the number of proxies or gateways that can forward the request.
 Min-Expires Header
 The Min-Expires header is used to limit the number of proxies or gateways that can forward the request.
 Retry-After Header
 The Retry-After response-header field RFC 3261 section 20.33 can be used to indicate how long the service is expected to be unavailable or when the called party anticipates being available again.
 Route Header
 The Route headers is used to store the route set of a transaction.
 Record-Route Header
 The Record-Route headers are used to establish a route for transactions belonging to a session.
 To Header
 The To header field specifies the "logical" recipient of the request.
 Via Header
 The Via header indicates the path taken by the request so far.
 Request-Disposition Header
 The Request-Disposition header syntax is defined in RFC 3841 section 10 as follows:.
 Accept-Contact Header
 The Accept-Contact syntax is defined in RFC 3841 section 10 as follows:.
 Reject-Contact Header
 The Reject-Contact syntax is defined in RFC 3841 section 10 as follows:.
 Event Header
 The Event header is used to indicate the which event or class of events the message contains or subscribes.
 Allow-Events Header
 The Allow-Events header is used to indicate which events or classes of events the notifier supports.
 Subscription-State Header
 The Subscription-State header is used to indicate in which state a subscription is.
 Call-Info Header
 The Call-Info header provides additional information about the caller or callee.
 Error-Info Header
 The Error-Info header provides a pointer to additional information about the error status response.
 In-Reply-To Header
 The In-Reply-To request header field enumerates the Call-IDs that this call references or returns.
 Organization Header
 The Organization header field conveys the name of the organization to which the entity issuing the request or response belongs.
 Priority Header
 The Priority request-header field indicates the urgency of the request as perceived by the client.
 Server Header
 The Server response-header field contains information about the software used by the user agent server to handle the request.
 Subject Header
 The Subject header provides a summary or indicates the nature of the request.
 Timestamp Header
 The Timestamp header describes when the client sent the request to the server, and it is used by the client to adjust its retransmission intervals.
 User-Agent Header
 The User-Agent header contains information about the client user agent originating the request.
 SIP-ETag Header
 The SIP-ETag header field identifies the published event state.
 SIP-If-Match Header
 The SIP-If-Match header field identifies the specific entity of event state that the request is refreshing, modifying or removing.
 Suppress-Body-If-Match Header
 The Suppress-Body-If-Match header field identifies a SIP event content already known by the watcher.
 Suppress-Notify-If-Match Header
 The Suppress-Notify-If-Match header is used to suppress superfluous NOTIFY transactions.
 Allow Header
 The Allow header lists the set of methods supported by the user agent generating the message.
 Proxy-Require Header
 The Proxy-Require header is used to indicate proxy-sensitive features that MUST be supported by the proxy.
 Require Header
 The Require header is used by clients to tell user agent servers about options that the client expects the server to support in order to properly process the request.
 Supported Header
 The Supported header enumerates all the capabilities of the client or server.
 Unsupported Header
 The Unsupported header lists the features not supported by the server.
 Path Header
 The Path header field is a SIP extension header field (RFC 3327) with syntax very similar to the Record-Route header field.
 Service-Route Header
 The "Service-Route" is a SIP extension header field (RFC 3608), which can contain a route vector that will direct requests through a specific sequence of proxies.
 Accept Header
 The Accept request-header field can be used to specify certain media types which are acceptable for the response.
 Accept-Encoding Header
 The Accept-Encoding header is similar to Accept, but restricts the content-codings that are acceptable in the response.
 Accept-Language Header
 The Accept-Language header can be used to allow the client to indicate to the server in which language it would prefer to receive reason phrases, session descriptions or status responses carried as message bodies.
 Content-Disposition Header
 The Content-Disposition header field describes how the message body or, in the case of multipart messages, a message body part is to be interpreted by the UAC or UAS.
 Content-Encoding Header
 The Content-Encoding header indicates what additional content codings have been applied to the entity-body.
 Content-Language Header
 The Content-Language header RFC 2616 section 14.12 describes the natural language(s) of the intended audience for the enclosed entity.
 Content-Type Header
 The Content-Type header indicates the media type of the message-body sent to the recipient.
 MIME-Version Header
 MIME-Version header indicates what version of the MIME protocol was used to construct the message.
 Warning Header
 The Warning response-header field is used to carry additional information about the status of a response.
 RAck Header
 The RAck header indicates the sequence number of the provisional response which is being acknowledged.
 RSeq Header
 The RSeq header identifies provisional responses within a transaction.
 Reason Header
 The Reason header is used to indicate why a SIP request was issued or why a provisional response was sent.
 Refer-To Header
 The Refer-To header provides a URI to reference.
 Referred-By Header
 The Referred-By header conveys the identity of the original referrer to the referred-to party.
 Replaces Header
 The Replaces header indicates that a single dialog identified by the header field is to be shut down and logically replaced by the incoming INVITE in which it is contained.
 Refer-Sub Header
 SIP header field Refer-Sub is meaningful and MAY be used with a REFER request and the corresponding 2XX response only.
 Authorization Header
 The Authorization header consists of credentials containing the authentication information of the user agent for the realm of the resource being requested.
 Proxy-Authenticate Header
 The Proxy-Authenticate header consists of a challenge that indicates the authentication scheme and parameters applicable to the proxy.
 Proxy-Authorization Header
 The Proxy-Authorization header consists of credentials containing the authentication information of the user agent for the proxy and/or realm of the resource being requested.
 WWW-Authenticate Header
 The WWW-Authenticate header consists of at least one challenge that indicates the authentication scheme(s) and parameters applicable to the Request-URI.
 Authentication-Info Header
 The Authentication-Info header contains either a next-nonce used by next request and/or authentication from server used in mutual authentication.
 Proxy-Authentication-Info Header
 The Proxy-Authentication-Info header contains either a next-nonce used by next request and/or authentication from proxy used in mutual authentication.
 Security-Client Header
 The Security-Client header is defined by RFC 3329, "Security Mechanism Agreement for the Session Initiation Protocol (SIP)".
 Security-Server Header
 The Security-Server header is defined by RFC 3329, "Security Mechanism Agreement for the Session Initiation Protocol (SIP)".
 Security-Verify Header
 The Security-Verify header is defined by RFC 3329, "Security Mechanism Agreement for the Session Initiation Protocol (SIP)".
 Privacy Header
 The Privacy header is used by User-Agent to request privacy services from the network.
 Session-Expires Header
 The Session-Expires header is used to convey the lifetime of the session.
 Min-SE Header
 The Min-SE header is used to indicate the minimum value for the session interval.


Sofia-SIP 1.12.6 - Copyright (C) 2006 Nokia Corporation. All rights reserved. Licensed under the terms of the GNU Lesser General Public License.