If you are a service provider or a corporate data center into which a remote location dials in during an emergency, you can configure the Services Router to accept incoming ISDN calls originating from the remote location.
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Incoming voice calls are currently not supported. |
When it receives an incoming ISDN call, the Services Router matches the incoming call's caller ID against the caller IDs configured on its dialer interfaces. If an exact match is not found and the incoming call's caller ID has more digits than the configured caller IDs, the Services Router performs a right-to-left match of the incoming call's caller ID with the configured caller IDs and accepts the incoming call if a match is found. For example, if the incoming call's caller ID is 4085321091 and the caller ID configured on a dialer interface is 5321091, the incoming call is accepted. Each dialer interface accepts calls from only callers whose caller IDs are configured on it.
The dialer interface of the Services Router and the dialer interface of the remote router must have the same encapsulation—PPP or Cisco HDLC. If the encapsulation is different, the call is dropped. Table 61Table 77 describes how the Services Router performs encapsulation monitoring.
Table 77: Encapsulation Monitoring by Services Router
This section contains the following topics: