Newb question about MM, how does it route VM to IP handset?

[surferdude949]

In a VoIP environment, how does MM knows where to send the voicemails when a user wants to retrieve a message from the IP handset.

Is it by IP address?

 

[9mmgeek]

The handset, any type not just IP, dials an extension on the phone system that connects to the voicemail system. It is usually a pre-configured button on the phone. The user logs in the plays their messages like a telephone conversation with a machine.

 

[9mmgeek]

To clarify. MM doesn't send messages to phones. Phones call MM to get the messages. Anything else MM needs to know is based on the extension.

 

[surferdude949]

Ok so the extension on MM is a digital port?

 

[pabxdude]

The voice path between MM and the PABX can occur in two ways - a station (either analog or digital) i.e. an NEC would use analog extensions, a Nortel would use 2616 digital sets. Or you can use trunks, E1/T1 QSIG, IP H.323 or SIP.

This is the bearer for voice. Along with this there is signalling that tells the MM how to handle to call. For example, E1/T1 and H.323 use QSIG to send messages about the call, as well as MWI on/off requests. SIP uses RFC compliant messages and the station method is different again, either an RS 232 link, or via reading displays of the digital sets once a call is answered.

Regradless of the method used, as stated before, stations (VoIP or TDM) dial an access number that send calls to the trunks/hunt groups. When MWI requests are sent, these go to the PABX for processing, so wether its an IP or TDM device, the PABX knows where it is registered and manages the requests(s)