On Tuesday 21 July 2015 14:30:51 Al S wrote:

I was wondering how can I replace From header username to perform the following authentication check with the new value:

route[AUTH]......if (!auth_check("$fd", "subscriber", "1")) { auth_challenge("$fd", "1"); exit;}...

http://www.kamailio.org/wiki/cookbooks/4.2.x/pseudovariables#fu_-_from_uri_u...

If changing the value doesn't work you need to use http://kamailio.org/docs/modules/stable/modules/textopsx.html#textopsx.f.msg...

But even that will not fix your problem, since it is not the From that is used for identification/authentication but the Authorization header set by the endpoint. And since the hash is calculated with this username by the endpoint, changing the username will break the process.