Duplicate Header Names

If more than one header exists for a configured header-name, the E-SBC stores each value in an array whose index starts at 0. To reference those values, use the syntax $<header-name>[<index>].

Add a trailing [<index>] value after the header-name parameter to represent the specific instance of the header on which to operate. Additional stored header values are indexed in the order in which they appear within the SIP message, and there is no limit to the index. The E-SBC takes no action if the header does not exist.

In addition to numerical values, possible index values are:

• ~ The E-SBC references the first matching header.
• * The E-SBC references all headers.
• ^ The E-SBC references the last stored header in the header rule.

Note that the header instance functionality has no impact on HMR’s add action, and you cannot use this feature to insert headers into a specific location. Headers are added to the end of the list, except that Via headers are added to the top.