Private Branch Exchange (PBX)

Private Branch Exchange (PBX)
Whether your company is new or expanding, an up-to-date and dependable PBX voice communication system can be an absolute must! It's like having your own miniature telephone company - at your business! A PBX located on your business premises can accomplish many of the voice communications functions associated with a telephone company. And it's private. It's an excellent solution for businesses with a large number of users. It functions as an autonomous communications network with all the whistles and bangles that you'll ever need. Look below to learn more about what it can do for your business.

What is a PBX?
A PBX is a private, digital telephone switching system usually owned and operated by a business. It is physically located on the business premises. It is used to direct calls among internal lines (intra-office) and between internal lines and outside lines (outside parties) by connecting to the PSTN. It allows a small number of outside lines to be shared among all of the people of the business.

Most PBX phone switches provide auto-attendant, voice-mail, and automatic call distribution (ACD) services for the business. A PBX system uses a computer to manage the call switching and telephone trunk lines that tie together multiple users. It also has a switchboard or console for an operator.

PBXs can be automatic, such as a private automatic branch exchange (PABX). They can also be manual, such as a private manual branch exchange (PMBX). A PABX routes calls based on the number dialed and does not require an on-site operator or attendant to switch the call. A PMBX requires manual assistance from an attendant.

Types of PBXs

Traditional PBXs - Traditional voice PBX systems use proprietary architectures, with call control and other computer telephony features offered as proprietary packages.

LAN PBXs - LAN PBXs come in a variety of architectures that integrate with LANs. Some LAN PBXs use unique Internet Protocol (IP) /Ethernet phones connected to LAN cable, and others use standard instruments and wiring for parts of the systems.

Ethernet PBXs - Ethernet PBX digitized voice and call control run over the same Ethernet LAN as your company's data. You can get excellent call control. You'll need IP or Ethernet compatible telephones. You'll still need traditional phone lines for fax machines.

Separate Voice and Data PBX Systems - Systems are available that use the LAN for call control and use standard telephone cabling for voice calls. A central PBX houses line cards and voice mail and may also hold a router, an e-mail server, a file transfer protocol (FTP) server, a file server, and other network devices. Though this solution keeps voice traffic off the LAN and works well with standard fax machines and phones, it requires a separate cabling system.

Hybrid PBX Systems - Hybrid PBX systems are available that use a separate 100Base-T LAN segment to carry digitized voice, but use standard telephone cabling to carry voice between the phones and the PBX. Call control runs over your existing LAN. A Windows NT server provides voice mail and links to computer telephony applications. This is a great solution for businesses with branch offices.

Wireless PBX - A wireless PBX system can be integrated into a PBX to provide mobile capability to a conventional wired telephone system. When integrated into a PBX, wireless service allows employees to use a portable telephone as a wireless extension to their desktop telephone.

Wireless PBX systems also allow the integration of mobile cellular service and local facility/campus communications. This gives users the ability to carry just one telephone with just one number.

What a PBX Does
PBX systems have capabilities for call handling, accounting, and priority management. LAN PBX systems extend call control features to LAN-connected PCs and provide a way to link applications to telephone systems. The PBX is centrally located at the business, typically in a wiring or phone closet. The PBX provides the physical connection between the outside line used by the caller, and the employee's phone on the desk. It is private because it is owned by the business. It is a branch exchange because it makes connections inside of the business in the same way that a normal telephone exchange connects all the phone numbers served by the phone company.

A PBX is used to cross-connect any outside line with any desired internal cabling or any outside line. It provides a dial tone, connects callers on one port to another, provides multi-party conferencing, and many other features. All of these operations are done automatically, either by dedicated PBX circuitry, or by computers controlling the PBX.

A PBX is the central source to which all telephone devices and outside phone lines are connected. PBXs offer many phone features including call queuing, user programmable features such as call forwarding, voice mail, 3-way conference calling and more. It routes all the calls as follows:

• Between users located at the business.
• From each user to people outside the business.
• From outside callers to users on-site at the business.

Why Use a PBX?
The main purpose of a PBX is to save the cost of requiring a line for each user to the telephone company's central office. It centralizes all functions at one module. Most medium sized and larger companies use a PBX because it's less expensive than connecting an external telephone line to every telephone on the premises. It's also easy to call someone since the number you need to dial is typically just three or four digits.

How It Works
The local telephone company brings outside phone lines into your business and trunks are wired to the premises. These outside lines and trunks are wired to jacks that connect to your PBX. The PBX connects together all of your internal users and the PSTN.

A PBX is an on-site system that functions as a switch. A switch is a computer that opens or closes a circuit at the beginning or end of a phone call. It chooses the destination on the network for a voice call, locates an open circuit, and then sends the call internally or externally.

Since the PBX system works autonomously, individual phones lines do not need to be tied directly to the phone company's central office (CO). In other words, a PBX eliminates the need for each user to be connected to the telephone company's network. All the users share the trunks so that each telephone path between the PBX and the CO can be shared by as many as eight to ten users. A trunk is a communication line connecting two switching systems, in this case - your PBX and the CO.

Installation
Installation and configuration of a PBX system can be done by the manufacturer or you may be able to install it yourself. Check with the vendor to determine if you can install it yourself.

Initial training on the system may also be offered. Many vendors encourage new customers to attend a training session or have a representative carefully instruct them on all the details about the new system.

Applications
PBXs are used mostly by medium and large sized businesses. PBXs handle big workloads with the number of users often in the hundreds. The system is essentially a smaller version of the switching equipment used by your local phone company to route calls. Most businesses use a PBX because it's much less expensive than connecting an external telephone line to every telephone in the organization.

PBXs provide reliable telephone service, telephony features and call control. They can handle a large number of users. Systems are available that offer a complete phone and data network solution including call control and management, e-mail, firewall, FTP, remote access, and a 10Base-T hub. If you have several hundred users in a single facility, or if you have multiple facilities and need a telephone system, we recommend that you consider a PBX.

Large PBX vendors are currently working on technologies that will enable these systems to support voice over IP, computer telephone integration and other new telecom technologies.

Benefits
Installing a PBX has many benefits as follows:

• Central on-site operation, control and management.
• Ease of deployment.
• Many features for expediting and facilitating communication.
• Management of the system is immediate, on-site, and on an as-needed basis.
• Private system with total control.
• Increased productivity.
• One initial payment with no built-in contract or monthly charges.

Technical Support
When selecting any business telephone system, technical support is an important consideration to keep in mind. Ask your salesperson what level of technical support is available for your particular type of PBX. Most manufacturers strongly support the system hardware and software. Most systems have comprehensive ongoing maintenance and support as well as a warranty. Check with your vendor for details.

Cost and Value
A PBX system comes at a premium. The benefits of having a system that can process and manage calls with superb efficiency is highly desirable for businesses. With a PBX,voice quality is always excellent and the phones are simple to use. Increased productivity will ensure that initial costs are covered.