Under SRST, you can still benefit of the voicemail system integration at the central site but this time instead to have an internal call to Unity, you need to make an outside calls to Unity when SRST is enbale.
So under the call-manager-fallback command, enable the voicemail <<VM_number_to_dial>> and your end-users will still have the opportunity to press the message button in SRST
A dialing domain is a group of Unity servers that share the same directory and do not require subscribers to use any type of prefix when performing transfers and sending messages between the servers (Extension must be unique within the dialing domain).
Unity can also integrate with other differents types of voice mail systems and is referred to as Unity networking.There are two overall categories of Unity networking:
- Networking with other Unity systems : This can be implemented using digital networking, SMTP networking or Voice Profile for Internet Mail (VPIMv2) networking depending on Unity version and specifications.
- Networking with traditional/Non-Unity Systems : This can be implemented using a bridge networking, an Audio Messaging Interchange Specifications (AMIS) networking or a VPIM networking.
The specific methods of networking Unity can be described as follows:
- Digital networking : This type of networking can be used to integrate Unity systems that share the same directory.
- SMTP networking : This can be used to integrate Unity systems that do not share a directory, but that are connected via IP.
- VPIM networking : This allows integrations of Unity with either other Unity systems or Non-Unity systems over an IP network such as the Internet. In this case of Unity-Unity Systems integration , it is obvious that the whole set can not share the same directory (AD forest).
- Bridge networking : This can be used to integrate Unity with an Octel voice mail system and requires the use of a Bridge server.
- AMIS networking : This allows Unity to integrate with Non-Unity systems over analog lines.
Take in mind that VPIM is a standard which is used by messaging systems to communicate messages over the Internet or other IP networks.
VPIM is based on the SMTP and Multipurpose Internet Mail Extension (MIMI) protocols. Because SMTP transport is used with VPIM, it is essential that the Exchange server used by a local Unity server, must be able to exchange email with the email system that the remote voice mail system is using.
When voice messages are sent using VPIM, they are typically converted into G726 (for Non-Unity systems) .For fax messages , they are encoded using a TIFF-F format.
Before messages can be sent between VPIM systems, they must be encoded as MIME messages, and with Unity this task is handled by the component called the Cisco Unity Voice Connector for Exchange (referred as Internet Voice Connector (IVC)). The IVC is also responsible for handling incoming VPIM messages in conjunction with the component called the VPIM Transport Event Sink.
Don’t forget also before to configure VPIM networking on Unity that you must complete several preliminary tasks as:
- Extending the AD schema
- Installing the IVC
Extending the AD schema is also a mandatory step to perform for Bridge networking.