Voice over IP

How does an IP PBX handle your calls when you are not there?

There are certain differences in which an IP PBX handles your calls when you are not there, when compared to say, an Analog PBX. There are additional functionalities with voice mail, call forwarding, double forwarding, ringing all sources, secret code, blocking certain numbers etc. These features of IP PBX which handle your calls when you are not there, are discussed in this article.

Voice Mail:

A voice mail, as you are aware, is a recorded message that your users leave when you are not there in your desk. In an analog PBX, the message can be retrieved from the phone by pressing a certain code. Also there are restrictions in the number of hours that a voice mailbox can record (These voice mailboxes are generally custom – either from the same manufacturer or from a different one). But in an IP PBX, the voice mail recording is only limited to the space available in your server, which can be expanded any time. Even IP phones come with their own voice mail alert system with blinking light, etc. But in an IP PBX, you can also get an email when a voice mail is recorded in your extension. Some vendors also provide a link (weblink) to the recorded voice mail, so that it can be listened to, when a user clicks on the link from his email (This feature needs to be enabled by your admin, though).

If the voice mail is full or if the user wants to reach another extension, he can do so with the help of prompts and by pressing certain keys. You could specify the number of seconds the IP PBX needs to wait before terminating the call (If the caller does not speak anything) and you could also specify the number of seconds the maximum recording time for a single voice mail could be. And more importantly, these things could be set by the user himself, using a web based interface, instead of relying on the administrator. Some service providers (SIP/VOIP) provide external mail boxes in their servers which could also be used for storing and retrieving voice mails.

Call forwarding/ Double Forwarding:

Call forwarding is an option that is also available with analog PBX. But here, the settings can be done by the user himself in a web based interface. Also, the calls could be forwarded to a land line/ call queue, another extension or a cell phone based on the time of the day in which the caller calls in. You can set rules like if it is the day, forward it to voice mail or a colleague or a cell no, if it is the night, then forward it to the cell no, if it is really late then forward it only to voice mail. These things are possible.

Double forwarding is a feature supported by certain IP PBX vendors where when the call is forwarded once to the cell phone, and even the cell phone doesn’t pick up, then it gets forwarded to a internal land line (a colleague, perhaps). Of course, the service provider needs to support this.

Ringing ALL sources:

Sometimes, you might not know yourself if you would be in the desk or away from the desk. In these times, this feature could be used. The IP PBX rings both the land line and your cell phone, and which ever is picked up first, the call is routed to that source. This can also be extended to two land lines and one cell phone ringing simultaneously. There may be additional call charges for receiving the calls in the cell phone.

Secret code:

Well, you want to forward the calls to your cell phone, but only certain numbers. You could do that with some IP PBX. You could set a pass key and if the caller is able to dial the pass key, then the call forwards to your cell phone. But you need to give the key to the caller before hand!

Block numbers:

You don’t want to listen to certain people on a particular day, then you could block such numbers and send them to voice mail straight! You can also do this based on the time of the day. But why you want to use such a feature is something we would not like to get into!!


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