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How Services Work

How Voicemail Systems Work

Voicemail is a technology that extends the power of the phone system.  Voicemail systems connect to and usually integrate with your office telephone system.  This tight integration usually results in more sophisticated features and capabilities.

Voicemail Basics

Most premise-based auto-attendant/voicemail systems are engineered to connect to a business telephone system (PBX or key system) as a telephone would.  This connection permits back-and-forth signaling (integration), letting the voicemail recognize a ringing line and answer it; access caller-id, dialed number, and other "call envelope" information; perform call transfers from its own ports to user extensions or "off-net" numbers; recognize do-not-disturb mode on a target extension; perceive ring-no-answer; retrieve a transferred call from an unanswered phone; light message-waiting lights on desk telephones, and perform other functions.

Methods for connection and integration vary.  Many third-party voicemail system integrate to PBX or KSU analog station ports (or higher-density T1 equivalents), and use DTMF/MF-type "inband" signaling - in effect, voicemail ports emulate black telephones.  In the past, such "analog integrations" had a reputation for being difficult to make, since the underlying signaling was noisy, slow, and inherently unstable.  But improved circuitry, better DSP and application code, better PBX documentation, and years of experience have improved matters.  Today, making an analog integration is often as easy as selecting the brand and model of PBX from a drop-down menu, or plugging in the voicemail and letting it auto-discover the tone-commands it needs to drive the switch.

Voicemail Ports

A voice mail system acts as a corporate receptionist, either tasked with answering and transferring calls, or delegated to  recording messages from people both inside and outside a company.  Meanwhile, each user is assigned an individual mailbox but all users share the ports available on the system.  

The number of ports is the single most important resource in determining how a voicemail system will perform.  Systems are sized according to the number of ports, or connections, that are established between the phone system and the voice mail system. Without an available port for the PBX to communicate with, it doesn't matter that your voicemail is loaded with features because callers will never reach it.  Most small offices have two to four ports, which allows a maximum of two or four simultaneous calls.  Therefore, having more ports means that more people can simultaneously leave or retrieve messages.  When configured as an automated attendant, the number of ports will dictate how many calls can be answered at any given time.

Ports also dictate the cost of a given system.  Prices, like features and capabilities, will vary.  Typically, you can expect to spend around $1000.00 per port.

How Callers Reach Voicemail

Your callers are directed to your voicemail system through one of the following:

a) your callers are connected with the automated attendant upon calling your office.
b) your telephone system is configured to forward calls to voicemail when the receptionist is busy, or when the telephones are not answered.
c) your telephone system is configured to forward calls to voicemail when transferred to a given extension that is busy or goes unanswered.
d) you transfer callers into voicemail.

After reaching your voicemail system, callers will be handled differently depending on your configuration.  Twenty-four (24) hours a day, callers can listen to pre-recorded information, receive fax documents, be transferred to you, leave you a message, have you paged, or interact with your voicemail system in some other way.


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