# SIP information elements

The following table lists the SIP IEs that NCC uses:

Information element (IE) | Type | Description
To Header IEs
SIP_IE_TO_ADDRESS | String | User address portion of the To header. To place a call, you can populate the address by setting the individual components or use SIP_IE_TO_FULL_ADDRESS.
SIP_IE_TO_HOST | String | IP address in the To header.
SIP_IE_TO_DISPLAY_NAME | String | Display name in the To header.
SIP_IE_TO_PORT | DWORD | Port number in the To header.
SIP_IE_TO_FULL_ADDRESS | String | Full SIP URI for the To header field. Use this IE to place a call.
SIP_IE_TO_URI_SCHEME | String | Scheme portion of the URI. For example, the scheme is tel in the example tel:+1234567.
SIP_IE_TO_URI_IDENTIFIER | String | Identifier portion of the URI. For example, the identifier is +1234567 in the example tel:+1234567.
From Header IEs
SIP_IE_FROM_ADDRESS | String | User address portion of the From header.
SIP_IE_FROM_HOST | String | IP address in the From header.
SIP_IE_FROM_DISPLAY_NAME | String | Display name in the From header.
SIP_IE_FROM_PORT | DWORD | Port number in the From header.
SIP_IE_FROM_FULL_ADDRESS | String | Full SIP URI for the From header field. Use this IE to place a call.
SIP_IE_FROM_URI_SCHEME | String | Scheme portion of the URI. For example, the scheme is tel in the example tel:+1234567.
SIP_IE_FROM_URI_IDENTIFIER | String | Identifier portion of the URI. For example, the identifier is +1234567 in the example tel:+1234567.
Registration IEs
SIP_IE_CONTACT_ADDRESS | String | Address at which the user can be contacted.
SIP_IE_REGISTRAR_ADDRESS | String | Address of the registrar.
SIP_IE_EXPIRES_HEADER | DWORD | Length of registration time in seconds.
SIP_IE_REGISTER_RENEW | DWORD | If this is a non-zero value, the SIP stack starts a timer and automatically renews the registration on the registrar before it expires.
Information for SIP message body using Transparent IEs
SIP_IE_CONTENT_TYPE | String | Content-type header in the SIP message.
SIP_IE_BODY | Data | Message body.
SDP information for SIP message body using SIP IEs
SIP_IE_SDP_PROTOCOL_VERSION | String | SDP protocol version.
SIP_IE_SDP_ORIGIN_USERNAME | String | User name in the origin field.
SIP_IE_SDP_ORIGIN_SESSION_ID | String | Session ID in the origin field.
SIP_IE_SDP_ORIGIN_VERSION | String | Version number in the origin field.
SIP_IE_SDP_ORIGIN_NETWORK_TYPE | String | IN
SIP_IE_SDP_ORIGIN_ADDRESS_TYPE | String | IP4
SIP_IE_SDP_ORIGIN_ADDRESS | String | Address in the origin field.
SIP_IE_SDP_SESSION_NAME | String | Session name.
SIP_IE_SDP_MEDIA_TYPE | DWORD | Media type. For valid values, refer to SIP_IE_SDP_MEDIA_TYPE.
SIP_IE_SDP_MEDIA_PORT | DWORD | Media port. For valid values, refer to SIP_IE_SDP_MEDIA_PORT.
SIP_IE_SDP_MEDIA_PROTOCOL | DWORD | Media protocol. For valid values, refer to SIP_IE_SDP_MEDIA_PROTOCOL.
SIP_IE_SDP_ENCODING | DWORD | Encoding. Use multiple entries if required. For valid values, refer to SIP_IE_SDP_ENCODING.
SIP_IE_SDP_CONNECTION_NET_TYPE | String | Network type: typically IN for Internet.
SIP_IE_SDP_CONNECTION_ADDR_TYPE | String | Address type: IP4
SIP_IE_SDP_CONNECTION_ADDRESS | String | Connection address: xxx.xxx.xxx.xxx
SIP_IE_SDP_ATTRIBUTE | String | Attribute.
Authentication IEs
SIP_IE_AUTH_USER | String | User name.
SIP_IE_AUTH_PASSWORD | String | Password.
Other SIP IEs
SIP_IE_SDP_ERROR | String | Error IE returned if incoming SDP contains an error.
SIP_IE_METHOD | String | IE that contains the SIP request or response message. For requests, SIP_IE_METHOD always contains a request name, such as INVITE or BYE. For responses, the contents of SIP_IE_METHOD differs depending on how the SIP server is configured. If the SIP server is configured to deliver extra information in the buffer attached to the generated event, SIP_IE_METHOD contains a three digit response code such as 100. If the SIP server is configured to deliver extra information in the buffer of NCC_PROTOCOL_EVENT, SIP_IE_METHOD contains the name of the request with which the response is associated. For information about configuring the SIP server, see Configuring the SIP server.
SIP_IE_OTHER_HEADER | String | IE that passes any user specified SIP headers to the SIP stack for inclusion in the SIP message.
SIP_IE_REQUEST_URI | String | URI from an incoming INVITE message.
SIP_IE_RESPONSE_CODE | Integer | IE that contains the response code associated with response messages: For SIP requests, SIP_IE_RESPONSE_CODE contains a value of 0. For response messages, SIP_IE_RESPONSE_CODE contains a three digit response code, such as 100. For more information, see Responses.
SIP_IE_CALL_ID | String | Call-ID header value.
SIP_IE_CSEQ | String | Command sequence header value.
SIP_IE_CONTENT_LENGTH | Integer | Length of SIP body.
SIP_IE_OPTIONS_HANDLE | DWORD | Options handle used to send the OPTIONS response (nccSendCapabilityResponse) or receive OPTIONS events.
SIP_IE_TRANSFER_TIMEOUT | Integer | User-supplied timeout in milliseconds for nccAutomaticTransfer.