Interworking ANM or CON with History-Info Headers
This interworking applies to SIP-I to SIP calls. If the 200OK message from the SIP side contains one or more history-info headers and you have set the redirection mode on the egress side to history-info, the SBC populates these parameters into the ANM/CON message.
When configured for native IWF and in receipt of History-Info information, the SBC interworks the following parameter groups:
- Redirection Number
- Redirection Number Restriction
Redirection Number
The SBC only adds this parameter for ANM messages. Redirection Number subfield interworking includes:
-
Nature of address indicator—The SBC inserts the following values, based on the conditions described:
- National, if there is no + in the number (encoded to 0000011).
- International, if there is a + in the number (encoded to 0000100).
- Internal Network Number Indicator—The SBC always inserts the value routing to internal network number not allowed (1).
- Numbering Plan Indicator—The SBC always inserts the value ISDN (001).
- Address Signal—The SBC inserts URI of the last History-info header with a cause parameter.
Redirection Number Restriction
The APRI is the only parameter interworked for this category:
- If the SIP Privacy or the priv-value component in the History-info entry containing a cause URI parameter is set to History, Session, or Header map the APRI to presentation restricted (01).
- If both the Privacy header or priv-value component in the last History-info header containing a "cause" URI parameter are absent or have any other value, map to presentation allowed (00).
Per the standard, the priv-value component in the history-info header can only have a value of either "history" or "none".