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Cisco BTS 10200 Softswitch SIP Feature and Provisioning Guide, Release 5.0
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Chapter2 SIP Subscribers
Cisco BTS 10200 Softswitch-Based Features
Step 8 If your VM server does not support FQDN hostnames, you must provision a serving-domain-name
record in the BTS 10200 using the IP addresses resolved from the sia-xxxCAnnn.domain address.
Otherwise, the VMWI status from SIP voice-mail platforms fails authentication with the BTS 10200.
The details for this step are provided in Step 6 of the “SIP Trunk to Voice-Mail Server” section on
page 3-46,
Provisioning Voice Mail Across Multiple Centrex Groups
A VM application server can provide VM service for Centrex subscribers from multiple Centrex groups
on the BTS 10200. For the VM server to identify the subscriber and provide service configured for a
Centrex group, the BTS 10200 must indicate the Centrex group with which the subscriber is associated,
When the BTS 10200 forwards a call from a Centrex extension to VM, the VM server identifies the
Centrex group of the extension to deposit the message in the correct mailbox. Further, when the VM
server sends a SIP Notify message to indicate that messages are waiting for a Centrex subscriber on the
BTS 10200, it must identify the Centrex group in the request URI of the NOTIFY message sent to the
BTS 10200.
For any INVITE sent out a SIP trunk by the BTS10200 to the VM server, a BTS 10200 proprietary SIP
URL parameter bgid is added to the From, To, Diversion, and Request URIs, if the user part of those
URLs contains a Centrex extension number format in the user information field. The bgid value is
provisioned as the trunk-subgroup-type on the SIP trunk, and identifies the Centrex group.
An example of this parameter syntax follows:
INVITE sip:50001@vm.cisco.com:5060;user=phone;bgid=grpA SIP/2.0
From: <sip:50603@bts.cisco.com;user=phone;bgid=grpA>;tag=1_1146_f40077_3jwv
To: <sip:50586@bts.cisco.com;user=phone;bgid=grpA>
Diversion: <sip:50586@bts.cisco.com;bgid=grpA>;reason=unconditional;counter=1
When the VM server notifies the BTS 10200 of a MWI for a Centrex subscriber, the VM server sends a
Notify SIP request to the BTS 10200 with a Centrex number format in the Request URL, and an
associated bgid parameter identifying the Centrex group associated with the subscriber. When the VM
server initiates a call to a BTS 10200 Centrex subscriber for VM callback functionality, bgid is added to
the request URL of the initial INVITE originating from the VM server. This identifies the Centrex group
associated with the subscriber.
The BGID parameter in the ReqUri of an INVITE originated from the VM server identifies the called
subscriber in the targeted Centrex group. For example, the BGID parameter in the ReqUri of a NOTIFY
message from the VM server to the BTS 10200 identifies the subscriber in the targeted Centrex group
whose MWI lamp is turned on or off.
The BTS 10200 does not support extension-dialed calls from one Centrex group to another. Therefore,
the bgid parameter has an identical value if it is present in any of the URLs in the From, To, Diversion,
and Request URL headers for a given INVITE message. The trunk group configuration includes a trunk
subgroup field for specifying the bgid parameter value. One trunk group is provisioned for each Centrex
group; the bgid parameter in the trunk group table is unique to the specific Centrex group. Routing tables
are configured so that each trunk handles SIP calls to and from the VM server for a specific Centrex
group. To qualify a specific trunk for bgid and VM, provision as follows:
•In the Trunk Group (trunk-grp) table, provision the bgid value in the trunk-sub-grp field.
•In the Softswitch Trunk Group Profile (softsw-tg-profile) table:
–
Provision the trunk-sub-grp-type field as BGID.
–
Provision the voice-mail-trunk-grp field as Y.