Nortel Networks NN10029-111 User Manual
Overview
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Copyright © 2003, Nortel Networks
MCP SIP Application Module Basics
Nortel Networks Confidential
details). If this step also fails, the SIP Application Module attempts a
general DNS A-record lookup to route the request.
general DNS A-record lookup to route the request.
Note: The DNS A-record is the traditional response given by a DNS.
It translates a domain name into an IP address.
It translates a domain name into an IP address.
If any of these steps succeed, the SIP Application Module routes the
request. If all these methods fail, the SIP Application Module rejects the
request.
request. If all these methods fail, the SIP Application Module rejects the
request.
Call Transfer service
The SIP Application Module handles the transfer on behalf of clients
that do not support the call transfer service.
The SIP Application Module handles the transfer on behalf of clients
that do not support the call transfer service.
The SIP Application Module supports unattended Call Transfer through
the Refer mechanism. Unattended Transfer (or Blind Transfer) refers to
cases where the transferor redirects the transferee to the transfer target
without first conferring with the transfer target. The transferor receives
a Notify message, however, indicating whether the transfer was
successful. If it was, the transferor releases the original call. If it was
not, the transferor is reconnected to the transferee.
the Refer mechanism. Unattended Transfer (or Blind Transfer) refers to
cases where the transferor redirects the transferee to the transfer target
without first conferring with the transfer target. The transferor receives
a Notify message, however, indicating whether the transfer was
successful. If it was, the transferor releases the original call. If it was
not, the transferor is reconnected to the transferee.
Local termination
The SIP Application Module first determines whether the incoming SIP
request terminates to a client in a domain managed by the
SIP Application Module. The SIP Application Module performs local
routing lookup through the Location Server, which is part of its internal
software.
The SIP Application Module first determines whether the incoming SIP
request terminates to a client in a domain managed by the
SIP Application Module. The SIP Application Module performs local
routing lookup through the Location Server, which is part of its internal
software.
Telephony routing
When the SIP Application Module receives an incoming call, it looks up
the callee in the database. If the callee is not in the database but the
domain is served and the user portion of the URL is a Telephony routing
number, the Telephony routing number is sent through the Telephony
routing software within the Location Server.
When the SIP Application Module receives an incoming call, it looks up
the callee in the database. If the callee is not in the database but the
domain is served and the user portion of the URL is a Telephony routing
number, the Telephony routing number is sent through the Telephony
routing software within the Location Server.
The Telephony routing software must perform digit translation to find a
gateway to terminate a call to. These tables are located in the Database
Module. You can provision them through the Provisioning Client. For
more information, refer to the SIP Provisioning Client User Guide and
the MCP Database Module Basics document.
gateway to terminate a call to. These tables are located in the Database
Module. You can provision them through the Provisioning Client. For
more information, refer to the SIP Provisioning Client User Guide and
the MCP Database Module Basics document.
The Telephony routing service allows the SIP Application Module to
•
provide unique dial plans for each subdomain
•
provide routes to gateways or to other domains