DIGITAL PHONE SYSTEMS : IP-PBX

VIVOSO

TRADITIONAL (OLD) PBX vs DIGITAL IP-PBX

IP-PBX(DIGITAL) triumphs over OLD Non-Digital PBX systems
The IP PBX has reached a new stage of maturity with shipments of IP lines expected to exceed those of traditional PBXs this year according to In-Stat. While the total PBX market is forecast to grow by a compound annual growth rate of 6.6% through 2009, the traditional PBX is in rapid decline, and the IP PBX will continue to gain momentum throughout the forecast period, the high-tech market research firm says.

"The IP PBX is revealing itself as more than a simple one-for-one replacement vehicle for digital systems," says Norm Bogen, In-Stat analyst. "With closer ties to data, this new vehicle is influencing corporate power structures and will ultimately have even more far-reaching effects on how business is done around the globe."

A recent report by In-Stat discovered that:

- Increased mobility both within and beyond the workplace will be a significant factor in the next stage of IP PBX development.
- Currently, tying voice with presence and instant messaging is gaining a strong foothold. But, the real changes will stem from adding more data and ultimately video to the mix of collaboration tools.
- Between now and 2009, server-based IP PBX shipments will grow from 9.5 million lines to 28.1 million, at which point such systems will represent over 91% of total PBX shipments.

The report, "IP PBXs: Emerging Into Dominance", covers the worldwide PBX market. It identifies market trends that are driving the growth of the IP PBX. It also features forecasts of PBX shipments and revenues by category through 2009. BY 2010 it will be over for LEGACY non IP-PBX systems. Companies like VIVOSO have led the way, having spun-off from VIVOPHONE a VOIP company, providing VOICE service and PBX is a perfect symbiosis.

Because of their overwhelming advantages, IP PBXs (PBXs that work over IP networks) are constantly replacing traditional PBXs and phone systems. If you have a company, however big or small it might be, a PBX is always beneficial, if economically feasible. Which PBX to choose? It will mainly be based on your business type and needs.

Other MAJOR considerations are integration with an existing PBX, reliability, support, features, operating system, training, and the state of your network.

More and more companies are making the transition to IP-based PBX systems because they offer flexibility and cost savings. In fact, some projections indicate that this year the number of IP PBX systems that are deployed will surpass the number of traditional PBX systems. Even so, it can be complicated to choose a PBX system that is right for your company. There are a lot of PBX systems on the market, and making a bad choice can have disastrous consequences. In this article, I will talk about some of the most important things to consider when purchasing an IP PBX.

An IP PBX is a private branch exchange, or telephone switching system, that routes calls over an IP network for internal users and provides access to outside lines. Typically, an IP PBX also switches calls between VoIP users and callers on traditional telephone systems. These products are usually software packages running on a server or dedicated appliances. IP PBXes eliminate the need for a separate voice network, instead converging voice and data traffic on the same network. The products offer a variety of call-management features, such as voice-menu systems, call conferencing, click-to-call, call logging and tracking, voice mail and call forwarding. With their IP PBXes, companies can chose to use softphones --software-only implementations of IP phones that run on users' desktops -- or traditional desktop phone sets designed to work over IP networks

Integration with existing legacy PBX
The first thing that you should consider when purchasing an IP PBX is whether or not the IP PBX that you are considering purchasing will integrate with a traditional (old-school)PBX. This is an important consideration even if you are planning on replacing your traditional PBX.

Think about it for a moment. If you disconnect your existing PBX, and then start setting up your IP PBX, the company will be without phone service until the new PBX is brought online and configured. You can prevent an interruption of service by adding the new IP PBX to the existing PBX system, and then gradually moving things over to the new system.

Reliability
In my opinion, the most important consideration when purchasing a PBX is reliability. After all, the phones are something that everyone expects to always work. If e-mail goes down, the first thing that people often do is to reach for the phone instead. As such, it is important to make sure that the IP PBX that you choose can deliver the reliability that people have come to expect. Besides, nobody wants to have to explain to the CEO why he can't get a dial tone, or why his call was cut off.

There are two main things that you can do to gauge the reliability of an IP PBX system. One thing that you can do is to look for reviews online. Computer geeks are notorious for blogging about hardware and software, and the odds are really good that you can find someone who has already deployed the IP PBX that you are considering purchasing. A blog entry will often tell you how the product is performing, but it may also offer some hints about getting past some of the more tricky configuration issues.

Another important way to gauge an IP PBX system's reliability is to look for features that make it reliable. For example, does the unit that you are considering provide automatic failover for voice clients? Is there another mechanism for establishing connectivity to the PSTN if your primary WAN connection fails?

Support
Once your IP PBX is up and running, you probably won't need a lot of support, but a PBX system is such a critical component of a company's infrastructure that you need to make sure that top-notch support is available whenever you need it. Therefore, it makes sense to verify that the company's support line is available 24 hours a day.

You should also make sure that the people working the support line are efficient and understandable. If I am calling a technical support line, it means that I have a problem that I need to resolve quickly. If the person working the tech support line is confusing to me, then it will take much longer to get the problem fixed.

While I am on the subject of support, be sure to check into the cost of the support. Some providers charge a fee for each support incident, while others offer annual support contracts.

Features
It is important to make sure that the IP PBX that you choose offers the features that you need, but don't get too hung up on choosing the product with the most features. It has been my experience that as a company's competitors offer more features, then a company will soon offer those same features to their customers through a firmware update.

Operating system
Another important criteria for choosing an IP PBX is the operating system that the unit uses. If you need to be able to customize the PBX software, then you will probably want to check into a Linux-based PBX that uses open source software. On the other hand, if your network is 100% Windows based, then you may be reluctant to bring in a Linux PBX, and might be happier investing in a Windows-based PBX.

Training
Another consideration when picking out an IP PBX is whether or not the manufacturer offers any kind of training. Don't expect your IT staff to just automatically know how to implement an IP PBX. Adding VoIP to a network requires a specialized set of skills, and the proper training is essential. You should consider the cost of training when determining the total purchase price.

Is your network ready?
Regardless of which PBX system you ultimately decide to purchase, you need to take a good, long, hard look at your network. Working in the field, I have seen a whole lot of poorly designed networks. In most cases, an inefficient design won't keep a network from working (although this isn't true in extreme cases). I have seen some really badly designed networks that were still perfectly capable of facilitating file transfers, e-mail, etc.

The problem is that VoIP requires a lot more bandwidth than data does. Adding an IP-based PBX to a poorly designed network has the potential to be disastrous. VoIP calls may become completely unreliable because the network is unable to deliver sufficient bandwidth, and data transfers may slow to a crawl. As such, I highly recommend making sure that your network is up to the job before you even consider purchasing an IP PBX.

Functions of a PBX
A PBX (Private Branch Exchange) is a switch station for telephone systems. It consists mainly of several branches of telephone systems and it switches connections to and from them, thereby linking phone lines.

Companies use a PBX for connecting all their internal phones to an external line. This way, they can lease only one line and have many people using it, with each one having a phone at the desk with different number. The number is not in the same format as a phone number though, as it depends on the internal numbering. Inside a PBX, you only need to dial three-digit or four-digit numbers to make a call to another phone in the network. We often refer to this number as an extension. A person calling from the outside might ask for an extension to be directed to the person she is targeting.

This picture illustrates how a DIGITAL PBX works.

The main technical roles of a PBX are:

To switch between telephone users thereby creating connections
To make sure the connection remains in place properly by keeping its resources
To properly end the connection when a user hangs up
To record the quantities, statistics and metering related to the calls
Practically, the functions of a PBX are the following:

Provide one single number that external callers can use to access all persons in a company.
Distribute calls to employees in a answering team in an even way; using the Automatic Call Distribution (ACD) feature.
Automate call answering, but offering a menu of options from which a user can select to be directed to a specific extension or department.
Allow the use of customized business greetings while answering calls.
Provide system call management features.
Place external callers on hold while waiting for a requested person to answer, and playing music or customized commercial messages for the caller waiting.
Record voice messages for any extension from an external caller.
Transfer calls between internal extensions.
IP-PBX
PBXs are not only for VoIP but have been around for landline telephone systems as well. A PBX that is specifically made for VoIP is called an IP PBX, which stands for Internet Protocol Private Branch Exchange).

Up to now, PBXs have been a business luxury that only huge companies could afford. Now, with IP-PBXs, medium-sized and even some small companies can also benefit from the features and functionalities of a PBX while using VoIP. True they have to invest some money into hardware and software, but the return and benefits are considerable in the long term, both operationally and financially.

The main benefits that an IP-PBX brings around are scalability, manageability and enhanced features.

Adding, moving and removing users to an from a telephone system can be very costly, but with an IP-PBX it is as cost-effective as it is easy. Moreover, an IP phone (which represents terminals in a PBX phone network) may not necessary to attached to one specific user. Users can transparently log in the system through any phone in the network; without however losing their personal profiles and configurations.

IP-PBXs are more software based than their predecessors and so maintenance and upgrade costs are considerably reduced. The work is easier as well.

PBX Software

Definition:

A PBX (Private Branch Exchange) is a small telephone switch owned by a company or organization. These organizations purchase PBX's to reduce the total number of telephone lines they need to lease from the telephone company. Without a PBX, a company will need to lease one telephone line for every employee with a telephone.

With a PBX system, the company only needs to lease as many lines from the telephone company as the maximum number of employees that will be making outside calls at one time. This is usually around 10% of the number of extensions.

In a PBX system, every telephone is wired to the PBX. When an employee takes the receiver off hook (i.e. picks up the telephone) and dials the outside access code (usually 9), the PBX connects the employee to an outside line (often, though somewhat incorrectly, referred to as a trunk).

PBX?

Overview
PBXs make connections among the internal telephones of a private organization - usually a business - and also connect 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.
PBXs are differentiated from "key systems" in that users of key systems manually select their own outgoing lines, while PABXs select the outgoing line automatically. Hybrid systems combine features of both.
Initially, the primary advantage of PBXs was cost savings on internal phone calls: handling the circuit switching locally reduced charges for local phone service. As PBXs gained popularity, they started offering services that were not available in the operator network, such as hunt groups, call forwarding, and extension dialing. In the 1960s a simulated PBX known as Centrex provided similar features from the central telephone exchange.
Two significant developments during the 1990s led to new types of PBX systems. One was the massive growth of data networks and increased public understanding of packet switching. Companies needed packet switched networks for data, so using them for telephone calls was tempting, and the availability of the Internet as a global delivery system made packet switched communications even more attractive. These factors led to the development of the VoIP PBX. (Technically, nothing was being "exchanged" any more, but the abbreviation PBX was so widely understood that it remained in use.)
The other trend was the idea of focusing on core competence. PBX services had always been hard to arrange for smaller companies, and many companies realized that handling their own telephony was not their core competence. These considerations gave rise to the concept of hosted PBX. In a hosted setup, the PBX is located at and managed by the telephone service provider, and features and calls are delivered via the Internet. The customer just signs up for a service, rather than buying and maintaining expensive hardware. This essentially removes the branch from the private premises, moving it to a central location.
History
The term PBX was first applied when switchboard operators ran company switchboards by hand. As automated electromechanical and then electronic switching systems gradually began to replace the manual systems, the terms PABX (private automatic branch exchange) and PMBX (private manual branch exchange) were used to differentiate them. Solid state digital systems were sometimes referred to as EPABXs (electronic private automatic branch exchange). Now, the term PBX is by far the most widely recognized. The acronym is now applied to all types of complex, in-house telephony switching systems, even if they are not private, branches, or exchanging anything.
PBXs are distinguished from smaller "key systems" by the fact that external lines are not normally indicated or selectable at an individual extension. From a user's point of view, calls on a key system are made by selecting a specific outgoing line and dialing the external number. A PBX, in contrast, has a dial plan. Users dial an escape code (usually a single digit; often the same as the first digit of the local emergency telephone number) that connects them to an outside line (DDCO or Direct Dial Central Office in Bell System jargon), followed by the external number. Some modern number analysis systems allow users to dial internal and external numbers without escape codes.

System components

A PBX will often include:
-The PBX's internal switching network.
- Microcontroller or microcomputer for arbitrary data processing, control and logic.
-Logic cards, switching and control cards, power cards and related devices that facilitate PBX operation.
-Stations or telephone sets, sometimes called lines.
-Outside Telco trunks that deliver signals to (and carry them from) the PBX.
-Console or switchboard allows the operator to control incoming calls.
-Uninterruptible Power Supply (UPS) consisting of sensors, power switches and batteries.
-Interconnecting wiring.
-Cabinets, closets, vaults and other housings.

Current trends

One of the latest trends in PBX development is the VoIP PBX, also known as an IP-PBX or IPBX, which uses the Internet Protocol to carry calls. Most modern PBXs support VoIP. ISDN PBX systems also replaced some traditional PBXs in the 1990s, as ISDN offers features such as conference calling, call forwarding, and programmable caller ID. However, recent open source projects combined with cheap modern hardware are sharply reducing the cost of PBX ownership.
For some users, the private branch exchange has gone full circle as a term. Originally having started as an organization's manual switchboard or attendant console operated by a telephone operator or just simply the operator, they have evolved into VoIP centres that are hosted by the operators or even hardware manufacturers. These modern IP Centrex systems offer essentially the same service, but they have moved so far from the original concept of the PBX that the term hardly applies at all.
Even though VoIP gets a great deal of press, the old circuit switched network is alive and well, and the already bought PBX's are very competitive in services with modern IP Centrexes. Currently, there are four distinct scenarios in use:
-PBX (Private and Circuit Switched)
-Hosted/Virtual PBX (Hosted and Circuit Switched) or traditional Centrex
-IP PBX (Private and Packet Switched)
-IP Centrex or Hosted/Virtual IP (Hosted and Packet Switched)
Since in reality people want to call from the IP side to the circuit switched PSTN (SS7/ISUP), the hosted solutions usually have to maneuver in both realms in one way or another. The distinctions are seldom visible to the end user.
Home and small business usage
Historically, the expense of full-fledged PBX systems has put them out of reach of small businesses and individuals. However, since the 1990s there has been a large set of small, consumer-grade and consumer-size PBXs available. These systems are not comparable in size, robustness or flexibility to commercial-grade PBXs, but still provide a surprising set of features.
The first consumer PBX systems were for the analog telephone systems, typically supporting four private analog and one public analog line. They are the size of a small cigar box or smaller and are inexpensive (e.g. US$50).
Particularly in Europe these systems for analog phones were followed by consumer-grade PBXs for ISDN. Using small PBXs for ISDN is a logical step, since already the basic rate interface of ISDN (which is the phone interface individuals and small businesses typically get) provides two logical phone lines (two B channels) which can be used in parallel. Small, entry-level systems are also extremely cheap (e.g. US$100).
With the pickup of VoIP by consumers, of course consumer VoIP PBXs have seen the light, and PBX functions have become simple additional features of consumer-grade routers and switches.

Open source projects have been available since the beginning of the 90s. These projects provide flexibility and features (often not needed or understood by average users), plus the means to actually inspect and change the inner working of a PBX. They have also opened business opportunities for newcomers to the market of mid-size PBXs, since they have lowered the entry barrier for new manufacturers. This is the future. Companies like FONAX (www.fonax.com) are perfect examples of new generation PBXs.

PBX functions

Functionally, the PBX performs four main call processing duties:
-Establishing connections (circuits) between the telephone sets of two users (e.g. mapping a dialled number to a physical phone, ensuring the phone isn't already busy)
-Maintaining such connections as long as the users require them (i.e. channelling voice signals between the users)
- Disconnecting those connections as per the user's requirement
-Providing information for accounting purposes (e.g. metering calls)
In addition to these basic functions, PBXs offer many other calling features and capabilities, with different manufacturers providing different features in an effort to differentiate their products. Common capabilities include (manufacturers may have a different name for each capability):
-Auto attendant
-Auto dialing
-Automatic call distributor
-Automated directory services (where callers can be routed to a given employee by keying or speaking the letters of the employee's name)
- Automatic ring back
-Call accounting
-Call forwarding on busy or absence
-Call park
-Call pick-up
-Call transfer
-Call waiting
-Camp-on
-Conference call
-Custom greetings
-Customised Abbreviated dialing (Speed Dialing)
-Busy Override
-Direct Inward Dialing
-Direct Inward System Access (DISA) (the ability t-access internal features from an outside telephone line)
-Do-not disturb (DND)
- Follow-me
-Interactive voice response
-Music on hold
-Night service
-Shared message boxes (where a department can have a shared voicemail box)
-Voice mail
-Voice message broadcasting
-Voice paging (PA system)
-Welcome Message
Interface standards
Interfaces for connecting extensions to a PBX include:
-POTS (plain old telephone service) - the common two-wire interface used in most homes. This is cheap and effective, and allows almost any standard phone to be used as an extension.
-proprietary - the manufacturer has defined a protocol. One can only connect the manufacturer's sets to their PBX, but the benefit is more visible information displayed and/or specific function buttons.
-DECT - a standard for connecting cordless phones.
-Internet Protocol - For example, H.323 and SIP.
Interfaces for connecting PBXs to each other include:
-proprietary protocols - if equipment from several manufacturers is on site, the use of a standard protocol is required.
-QSIG - for connecting PBXs to each other, usually runs over T1 (T-carrier) or E1 (E-carrier) physical circuits.
-DPNSS - for connecting PBXs to trunk lines. Standardized by British Telecom, this usually runs over E1 (E-carrier) physical circuits.
- Internet Protocol - H.323, SIP and IAX protocols are IP based solutions which can handle voice and multimedia (e.g. video) calls.
Interfaces for connecting PBXs to trunk lines include:
- standard POTS (plain old telephone service) lines - the common two-wire interface used in most domestic homes. This is adequate only for smaller systems, and can suffer from not being able to detect incoming calls when trying to make an outbound call.
- ISDN - the most common digital standard for fixed telephony devices. This can be supplied in either Basic (2 circuit capacity) or Primary (24 or 30 circuit capacity) versions. Most medium to large companies would use Primary ISDN circuits carried on T1 or E1 physical connections.
- RBS - (Robbed bit signaling) - delivers 24 digital circuits over a four-wire (T1) interface.
- Internet Protocol - H.323, SIP, MGCP, and Inter-Asterisk eXchange protocols operate over IP and are supported by some network providers.
Interfaces for collecting data from the PBX:
- Serial interface - historically used to print every call record to a serial printer. Now an application connects via serial cable to this port.
- Network Port (Listen mode) - where an external application connects to the TCP or UDP port. The PBX then starts streaming information down to the application.
- Network Port (Server mode) - The PBX connects to another application or buffer.
- File - The PBX generates a file containing the call records from the PBX.
The call records from the PBX are called SMDR, CDR, or CIL. It is possible to use a Voice modem as FXO card.
Hosted PBX systems
A hosted PBX system delivers PBX functionality as a service, available over the Public Service Telephone Network (PSTN) and/or the internet. Hosted PBXs are typically provided by the telephone company, using equipment located in the premises of the telephone company's exchange. This means the customer organization doesn't need to buy or install PBX equipment (generally the service is provided by a lease agreement) and the telephone company can (in some configurations) use the same switching equipment to service multiple PBX hosting accounts.
Instead of buying PBX equipment, users contract for PBX services from a hosted PBX service provider, a particular type of application service provider (ASP). The first hosted PBX service was very feature-rich compared to most premise-based systems of the time. In fact, some PBX functions, such as follow-me calling, appeared in a hosted service before they became available in hardware PBX equipment. Since that introduction, updates and new offerings from several companies have moved feature sets in both directions. Today, it is possible to get hosted PBX service that includes far more features than were available from the first systems of this class, or to contract with companies that provide less functionality for more simple needs.
In addition to the features available from premises-based PBX systems, hosted-PBX:
- Allows a single number to be presented for the entire company, despite its being geographically distributed. A company could even choose to have no premises, with workers connected from home using their domestic telephones but receiving the same features as any PBX user.
- Allows multimodal access, where employees access the network via a variety of telecommunications systems, including POTS, ISDN, cellular phones, and VOIP. This allows one extension to ring in multiple locations (either concurrently or sequentially).
- Supports integration with custom toll plans (that allow intra company calls, even from private premises, to be dialed at a cheaper rate) and integrated billing and accounting (where calls made on a private line but on the company's behalf are billed centrally to the company).
- Eliminates the need for companies to manage or pay for on-site hardware maintenance.
Mobile PBX
A mobile PBX is a hosted PBX service that extends fixed-line PBX functionality to mobile devices such as cellular handsets, smartphones and PDA phones by provisioning them as extensions. Mobile PBX services also can include fixed-line phones. Mobile PBX systems are different from other hosted PBX systems that simply forward data or calls to mobile phones by allowing the mobile phone itself, through the use of buttons, keys and other input devices, to control PBX phone functions and to manage communications without having to call into the system first.

Good reference articles:

http://blog.tmcnet.com/blog/tom-keating/voip/ippbx-eclipses-traditional-pbx.asp

http://searchwarp.com/swa241403.htm

IP PBX Gains On Traditional PBX
http://blogs.zdnet.com/ip-telephony/?p=87

IP PBX Hybrids Are the Wave of the Future
http://www.ecommercetimes.com/rsstory/51207.html

http://en.wikipedia.org/wiki/IP_PBX

http://www.answers.com/topic/ipbx

http://www.computerweekly.com/Articles/2007/02/01/221596/unified-communications-to-fuel-pbx-demand.htm

BOOKS

http://books.google.com/books?id=mju7kMdNxwkC&pg=PA228&lpg=PA228&dq=traditional+pbx+vs+ip-pbx&source=bl&ots=S2S8sLbKLS&sig=dhfdl2eyCSZS9gAqwgQEsM5ap0A&hl=en&sa=X&oi=book_result&resnum=8&ct=result

VIDEOS

PBX SECURITY

PBX TIPS for SMB

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SETTING UP Your BUSINESS (Small Business Resources)

Which best describes your phone system project:
-Installing a new phone system
-Replacing an existing phone system
-Expanding an existing phone system

How many in the company:

-at least 4
-4-5
-6-9
-10-14
-15-19
-20-29
-30-49
-50-69
-70-99
-100-199
-200+

Do you need:

-Automated attendant
-Advanced call routing and tracking features
-Music or advertising on hold
-Computer telephone integration
-Voicemail

CONTACT a Digital Phone System Solution consultant to discuss, at no charge

A VIVOSO PBX offers:

-Advanced PBX functionality combined with local and long distance calling from one service provider.

-Reduced Total Cost of Ownership (TCO) due to minimal upfront investment and low monthly service fees.

-Smooth business telecommunications for companies operating from a single location or branch offices…including out-of-office and home based employees.

-Works with any high speed Internet connection to provide all users with access to the same PBX features regardless of their location anywhere.

-Dramatically lowers monthly phone bills with free in-network inter-office calls and unlimited local and long distance calling plans.

-Customizable, easy to use features managed online and by one touch controls using any desktop/laptop computer.

VIVOPHONE PBX SYSTEM:

System Features
Online PBX Controls (system management interface)
Multiple Auto-Attendants
Day and night modes - 'time-based routing'
Voicemail
Flexible routing
Terminate extensions to any 10 digit number
Transfer to any outside number (including cellular phones)
Conferencing
Music on hold/transfer
Custom music/message on hold/transfer
Directory on phone
Intercom
Dial by extension
Dial by name
Record greeting remotely
Record user names
Hardware- and software-based options
and more!
Phone Features
Caller ID
Call Waiting
Call Forwarding
Find Me/Follow Me
Call Transfer
Last Number Redial
Speed Dial
Three-Way Calling
Voicemail Features
Password protected
Unavailable/busy/temporary greetings
Voicemail to email (delivered as .wav file)
Remote access
On-phone "message waiting" indicator

Basically:

Auto Attendant
Customers can be automatically routed to the right extension.

Advanced Voicemail
Have your voice messages sent directly to your email account.

Custom Messages
Callers can hear customized messages while on hold.

Dial-in Conferencing
Virtual conference rooms where everyone can connect.

Call Forwarding
Easily transfer or forward calls, even your cell phone.

Portable Extensions
Phones work the same at the office, at home or on the road.

IP-PBX
An IP PBX handles voice signals under Internet protocol, bringing benefits for computer telephony integration (CTI). An IP-PBX can exist as physical hardware, or can carry out it functions virtually, performing the call-routing activities of the traditional PBX or key system as a software system. The virtual version is also called a "Soft PBX" .

An auto-attendant with a customized, professionally recorded greeting, multi-level menus, voicemail, faxing, conferencing and administrative tools for tracking usage and managing users.

A Vivophone PBX System can be tailored to any business because the system can be configured with any Web-based application. It's no exaggeration to say that Vivophone VOIP + PBX represents the future of unified communications. Who will seize the opportunity to bring Business VoIP to millions of medium, and small companies?
Tons of major corporations have been switching from expensive, outdated, analog telephone service to feature-rich, robust, cost-saving Voice Over Internet Protocol (VoIP) telephone systems. Most companies will soon realize the advantages to switching to VoIP. Vivophone is here.