Voice mail

Voicemail is an electronic system for registering, saving and redirecting telephone voice messages (sometimes for tracing and notifying users).

Currently, voice mail is understood as two types of services provided by operators and mail servers :

An opportunity for a telephone network subscriber to leave a voice message to an addressee , which he can listen to later.

The ability to listen on the phone stored on the e-mail server messages read by the robot.

Content

Voicemail as an Operator Service

The voice mail service is provided to subscribers by almost all mobile operators and some traditional telephony operators . This service allows you to record voice messages of subscribers, access to which can then be obtained from your phone or via the Internet. To use the service you need a telephone that can operate in the frequency (tone) dialing mode.

Voice Mail as a PBX Service

In corporate telephony, voicemail (voice mail system) refers to a device that connects to an office (office) PBX to subscriber telephone lines and allows each PBX subscriber to receive voice messages in a personal mailbox.

A subscriber listens to messages from a telephone when calling a specific telephone number.

Some system telephones have an indicator (light) informing about the appearance of new messages in the mailbox.

Voicemail constructively can be:

PBX extension board (such boards are issued by manufacturers of PBXs)
stand-alone device for desktop installation (produced by a mass of third-party manufacturers, used by small and medium-sized businesses)
functionally complete unit for installation in a 19 "rack (also produced by third-party manufacturers, used in large and medium enterprises)

Modern voice mail is equipped with an auto attendant , which provides the ability to dial a number, as well as the ability to send voice messages to e-mail subscribers (when connected to a LAN ).

Phone Call Processing Scheme

Voicemail - Phone Call Processing Scheme

The figure shows the operation of voice mail when processing telephone calls. Voice mail is connected to the subscriber line of the PBX. Voicemail has a built-in auto attendant.

Call flow chart:

“Subscriber 1”, connected to the public telephone network , dialed the office telephone and was automatically transferred to voicemail
“Subscriber 1” dialed the number of the internal “Subscriber 2” (thanks to the auto attendant function), where the call was transferred
“Subscriber 2” did not answer for some time and the call of “Subscriber 1” was automatically returned to voicemail, where “Subscriber 1” was asked to leave a voice message to “Subscriber 2”.

Voice Mail System Features

Typical features of voice mail systems include:

number of telephone lines: 2 - 8 (so many messages can be recorded simultaneously)
number of mailboxes: 20 - 500
number of messages in the mailbox: 50 - 100
maximum message duration: up to 10 min.
total message length: 5 hours - 100 hours