Asterisk Phone System Baltimore MD

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A division in telecom has always existed between the engineers that transfer data and the engineers that work on voice service. In general, these are different types of people, and they don’t hang around with each other. Asterisk brings them both together for the first time. It allows you to handle voice calls with the same mind-set of routing data.

This article introduces you to the depth and breadth of what you can do with Asterisk. We cover the general types of calls and features as well as the varieties of telephony platforms you can use to interact with Asterisk.

Finding Out What You Can Do with Asterisk

Asterisk bridges the methodical, planned open-source architecture previously the sole domain of data transmissions and takes it into the voice world dominated by rigid proprietary phone systems. The intelligence and flexibility of telecom hardware available to the person on the street has grown at a very fast pace over the past 20 years.

In the future, Asterisk has the power of bringing together people from around the world for free. VoIP connections handled entirely across the public IP network don’t incur per-minute charges like a normal phone call. Only when the proprietary networks of the long-distance and local phone companies handle a call do per-minute charges apply. Otherwise, the transmission travels across your office or across the world for free, just like an e-mail.

In the beginning, Asterisk was rumored to have been designed as a voice-mail system. That is by no means the limit of its potential; voice mail is simply the beginning of its capabilities. The software now functions as a platform for receiving and transferring calls with all the standard features you want from a phone system, such as

Voice mail, which allows callers to record a voice message when you are on your phone line or away from the office

Conference calling, which provides the ability for multiple people to call into your Asterisk and talk together just as if they were all physically sitting in the same conference room

Dial-by-name directory, which allows callers to reach an extension by spelling out the first or last name of the person of the person they are calling on the keypad of their phone

Call parking, which sends a call someplace to wait on hold

Music on hold, which gives callers something to listen to while you have them on hold

These same features are available with any phone system. You need to purchase hardware to allow you to use either dedicated digital (T-1) lines or regular, analog, plain old telephone service (POTS) lines.

You can use Asterisk as your phone system without ordering any standard analog or digital phone lines from your local carrier. As long as you have a dedicated Internet connection to your home or office, you can purchase incoming and outgoing phone service from your Internet Service Provider (ISP) and never have to worry about standard phone lines.

The main benefit of Asterisk is its flexibility. You aren’t locked in to any preset parameters of the phone system. Some of the great features you have complete control over with Asterisk are as follows:

How you receive calls

Whether a call is sent directly to voice mail

Whether a call is sent directly to a conferencing room, where several people can speak on the same conversation

How calls are routed within your phone system and your company

How to forward calls (such as first to your landline, then to your cellphone, and then to voice mail)

How much time you allot before you rescind the call and transfer it to the next destination (such as a cellphone or voice mail)

The extensions and features available to every phone and piece of hardware

One of the best aspects of Asterisk is the ease with which you can integrate the ability to send and receive calls over your dedicated Internet connection. Voice over Internet Protocol, more commonly referred to as VoIP, is the greatest revolution to hit telephony since the dial tone. All the benefits of VoIP have yet to be realized, but Asterisk comes standard with the ability to convert your voice call into VoIP packets.

One of the fastest growing applications of Asterisk is its use with VoIP. Many companies have sprung up for the sole purpose of providing advanced features to their customers via VoIP. The “find-me-follow-me” type of service that allows one call to attempt to reach you on your office line and then your cellphone, before the call is rescinded and sent to your voice mail, is just one of the great features of VoIP. You can even e-mail your voice mail as a WAV file to your BlackBerry or Palm device. Talk about never missing a call again. If you are breathing and available by any means of technology, Asterisk can find you.

The future of telecom is in the transmission of voice, fax, and video over Internet lines. The ability to packetize all these transmissions into the IP realm is a huge step forward in telecom. It allows for growth at an accelerated pace as the transmissions are handled together, maximizing the bandwidth of every connection. By breaking the mindset of traditional telephony where every voice call is locked into a 64Kbps channel, we lose the hardware requirements preventing us from using the Internet over our regular residential phone lines.

VoIP is great, but not every piece of hardware you may need to use is VoIPbased. You may use VoIP service within your office but have a better rate for out-of-state calls on a carrier that doesn’t have a VoIP interface. In this case, you have to send the call with the standard, non-VoIP method using traditional time-division multiplexing (TDM) connections.

Not every long-distance carrier has the VoIP service you want. Some carriers only provide inbound VoIP service to avoid providing directory assistance, 411, and 911 services. Other carriers may avoid these requirements entirely by boycotting VoIP connections.

Your local or long-distance carrier may charge you differently for VoIP than for TDM service. The per-minute rate you are charged may be different, the area of coverage provided may be restricted, or additional monthly recurring charges or installation fees may apply.

Just because your carrier may not accept VoIP calls doesn’t mean that you can’t use VoIP somewhere in your system. You simply need to convert your calls from VoIP to TDM, or TDM to VoIP, when you enter or leave your carrier’s network. The ability of Asterisk to act as a gateway (converting calls from VoIP to TDM or vice versa) gives you the freedom to use every telephony option at your disposal.

You aren’t confined to traditional landlines with Asterisk, so don’t get trapped by that old private branch exchange (PBX) mind-set. In the land of wireless technology, Asterisk is a good friend. It can easily interface with any of the following devices:

Regular cordless phones

Cordless VoIP phones

Wireless headsets connected directly to your computer via Bluetooth

You can use most Bluetooth wireless headsets that you use with your cellphone. You use your computer as the audio device and pair it with any VoIP software phone (softphone) for your PC. This configuration allows you to make calls from your softphone via your PC with VoIP. Asterisk implements its own Bluetooth channel driver, allowing Asterisk to function as your softphone on your PC.

Using Asterisk for your internal company calls is only the starting point of its potential. Many companies, especially VoIP-based resellers, may run their entire business on Asterisk servers. If you run a telephony business, you’ll find the following useful features in Asterisk:

Flexibility in programming

Reporting features

Call Detail Record (CDR) logs

The ability to use TDM, VoIP, and wireless connections

But the fun doesn’t stop there. Asterisk is easily partitioned for multiple companies to use all the available features, but still confine their calls to within their company. You don’t have to worry about pressing 0 to speak to an operator at Company A and getting the receptionist for Company B. This requires a bit more effort because you must partition all the calls by company in your CDR.

Multilocation corporations that have offices in different states or even countries can use Asterisk to virtually eliminate long-distance calls between offices. Installing an Asterisk at each location allows you to send and receive VoIP calls, taking your standard long-distance calls from your existing carrier. Just as e-mail eliminates the need for sending letters through the post office, VoIP now allows you to bypass your local phone carrier.

If you are using the Asterisk internally, a basic configuration should cover most of the scenarios you might encounter. If your company is a telecom reseller that provides phone service to customers, possibly as a VoIP value-added reseller, your configuration needs to be a bit different. In spite of the fact that you might have a few phones in your office attached to the Asterisk server, Asterisk primarily processes your end users’ calls.

Asterisk is the best platform for VoIP resellers because you can expand and build on it as your business grows and becomes more complex. You can realize a configuration as grand as your company can become. Your setup can range from a single server that provides central call processing for multiple offices using VoIP phones to multiple servers that process calls from multiple offices that use (a) VoIP phones directly and (b) VoIP PBXs such as Asterisk to fulfill all their office needs.

A PBX is a common phone system that you would find in an office environment. It generally provides voice mail, call transfer, call hold, and the general routing of calls handled by an office phone system.

Getting Acquainted with AsteriskNOW

AsteriskNOW is a complete software package, which allows you to load Asterisk software and a distribution of Linux operating software on a server. After you complete the installation, you can configure it using an Internet GUI. All the regular features provided in Asterisk, such as voicemail, conference call setup, call queuing and dialplans, are also available through the AsteriskNOW release.

AsteriskNOW makes Asterisk available to a much broader range of companies and individuals. The idea of working in a Linux operating environment and building the routing rules with manual programming might be too much for some. For those who want to the power of Asterisk, but don’t have the time to build out the programming, AsteriskNOW is your ticket.

AsteriskNOW is just like the standard version of Asterisk in its hardware requirements. It’s a real-time program requiring the full and undivided attention of your server. Whether you are using the software as a phone system for your business or as a basis for the value-added telecom service you are providing, you must have it on the best hardware possible. Regardless of the size of your company or server, the Asterisk program must be given top priority in all tasks to reduce the chance of network delays degrading the quality of your calls. A modest amount of delay caused by other network activity can result in static or sections of calls being dropped. At the other end of the spectrum, large delays could result in static or the failure to connect both inbound and outbound calls.

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For Dummies is a registered trademark of Wiley Publishing, Inc. in the United States and other countries. Used here by license.

A T & T

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Baltimore, MD
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