Должно возвращаться в таком формате (хоть и типа кошкин, но много кто использует)
Надеюсь переводить не надо
h323-ivr-in=Routing:[[cld]@]hostname[:port][;credit-time=seconds][;expires=seconds][;auth=username:password][;cli=cli][;ash=ash][;np_expires=seconds]
Options in square brackets are optional parameters. The underlined words denote variables to be filled in by the RADIUS server. If more than a single routing entry is present, routing entries will be tried one by one until either there are no more routes left or the call is successfully connected. The following parameters are available:
cld - CLD to be used for the outgoing call
hostname - IP address or DNS name of the SIP peer to which the call must be sent
port - UDP port at which the SIP peer to which the call must be sent accepts SIP signaling messages
credit-time - maximum session time to be allowed before the call is forcefully disconnected by the B2BUA
expires - maximum time to wait until the call sent to a particular route is connected. If this time has been exceeded, the B2BUA proceeds to processing the next route if one or more routes is available, or reports a failure condition to the caller if not available.
auth - username/password pair for SIP authentication with a remote SIP peer at hostname
cli - CLI to be used for the outgoing call
ash - insert arbitrary SIP header field into INVITE of the originate call leg. The parameter value should be a valid SIP header field in the format Name:Value, transformed using URL quoting rules set forth in RFC 1738.
np_expires - maximum time to wait until non-100 provisional response on the call sent to a particular route is received or the call is connected (whichever happens first). If this time has been exceeded, the B2BUA proceeds to processing the next route if one or more routes is available, or reports a failure condition to the caller if not available.
The following is an example of a routing string in the RADIUS attribute:
h323-ivr-in = 'Routing:200110508667@b2bua.org;cli=16046288900;rid=-1;expires=30;np_expires=5;ash=Name%3AValue'
взято отсюда:
http://b2bua.org/wiki/B2BUADocumentation