INTERCOMM / PABX
PABXs make connections among the internal telephones of a private organization — usually a business — and also connects them to the public switched telephone network (PSTN) via trunk lines. Because they incorporate telephones, fax machines, modems, and more, the general term "extension" is used to refer to any end point on the branch.
PABXs are differentiated from "key systems" in that users of key systems manually select their own outgoing lines, while PBXs select the outgoing line automatically. Hybrid systems combine features of both.
A PABX (Private Automatic Branch Exchange) is essentially an automatic (exchange) switchboard for telephone systems. The essential features are to provide switching and connection between any two (or more) telephone users and make sure the connection remains in place until it is ended, at which point the system properly terminates the connection.
Any system that does this automatically for telephone calls within an organization is a PABX. The reason businesses move to PABXes is to avoid requiring every employee to have a direct line to the public telephone system, each of which incurs a connection and a line charge. Instead, a smaller number of lines get shared by all the users and managed by the PABX. This saves money and is more efficient.
All PABX systems are basically exchange and extension managers for calls based on Internet protocol – also known as VoIP and Internet telephony. The essential advantage they offer to small- to medium-sized businesses is the ability to add features that have only been affordable or available to large businesses up to now. VoIP and Internet telephony are usually also more cost-effective when looking at long-term operating costs, due to lower monthly fees and much lower costs to connect and complete calls.
There are three basic kinds of premise-based phone systems. The first kind is called keyless systems or KSU-less systems. They are very lightweight phone systems designed for organizations with fewer than 10 employees that also have very basic phone requirements. The advantage of these systems is that they are very inexpensive and very easy to set up and run. They are portable and can be moved easily if you relocate. However, in a typical keyless sytem, you get very little support and maintenance from your service provider. Also, additional features – such as those that prevent users from picking up a line in the middle of another call – are often impossible to implement.
These systems are so simple that they are not considered PABXes and are in fact being phased
The benefits of an IP PABX to any enterprise are similar to and different from the benefits of a VoIP system in general. Obviously, the cost savings and reduction in basic wiring infrastructure from needing only one network for communication instead of two are clear. And the savings from the lower basic cost of completing external calls are also clear. But IP PABX brings far greater benefits because of manageability, upgradeability and enhanced feature sets.
GENERAL BENEFITS
The specific benefits of an IP PABX over traditional phone systems or PABXes include the following :
A cleaner and simpler infrastructure
Lower operating costs.
Simplified equipment and maintenance
Unified communications
Improved scalability and growth
Improved features for business operations
Improved technological features and capabilities
SPECIFIC BENEFITS
Conference Calls – Can easily conference large numbers
Mobility -Easily add remote users of any kind.
Phones - Can be programmed to provide internal and external apps of all kinds.
Efficiency - More efficient use of network.
Basic Features
Residential and very low-end VoIP providers often claim to offer business-class PBX services, but except for very small organizations, that just isn’t the case. Even the most basic businesses now require a set of capabilities that would not have been possible even for the largest corporations 20 years ago.
In addition to the default PBX features like call switching, call completion, call connection, call termination and accounting, the following should also be found in any premise-based IP PBX system:
Call Routing Features
Automated Attendant
An automatic system to answer phones with the ability to build phone menu systems, add call menus, transfer to voice mail and create flexible and programmable rules to handle all of these features.
Call Menus
Flexible call management menus with user selectable options – a more advanced version of the traditional phone tree/menu systems. A better-quality system will let you have multiple sets of menus and even change them based on time or on information gleaned from caller ID.
Managing Extensions
Features to help the phone system administrator, such as the ability to add new extensions, remove unneeded extensions, change extension locations and much more from a Web-based control panel.
Call Forwarding
Automatic, programmed or manual call forwarding to any number.
Call Transfer
The ability to transfer calls between extensions without going back to a central switchboard.
Call Parking
Essentially a group hold – put the caller on hold in a waiting area so that any other phone system user can pick the call up.
