I am often asked what is required connect multiple sites for 3 or 4 digit dialing or shared call handling. Viable options vary depending on location, size, and needs at each site, but these are the basics.
Any worthwhile solution is going to be VoIP (voice over IP) based. You will be running voice calls over either a private data network, the Internet, or some combination of the two. Solutions may be designed around either premised based IP or hybrid telephone systems such as those manufactured by NEC, Avaya, Mitel, Cisco, Shoretel or some type of cloud "hosted" solution. A premise based system will require some combination of on site processor/server with cards and/or licenses. Most premise solutions offer their highest level of functionality with proprietary telephones or softphones The hosted solution may utilize proprietary telephones or open SIP IP telephones, softphones. Typically a processor/server is not installed on site, but depending on needs and configuration additional router or data [can phone] switch gear may be required.In general, large enterprises with complex needs, private data networks and the resources to support in-house equipment will want to take a hard look at premised based IP PBX while small and medium size organizations may find that going with a hosted solution is by far the most sensible solution. Hosted solutions can offer a way to connect all sites, have instant access to high level features like unified messaging, and take control of your own phone numbers for a fraction of the cost of premise solutions. Also, hosted solutions are typically highly scalable allowing new telephone lines, phones, and features to be quickly deployed as a business grows with out the need to buy additional cards, cabinets, licenses, and phone company lines to grow.
So going with a cloud based system sounds like the way to go for most businesses, but with hosted telephone systems there are some caveats. The IP phones are devices on your network and your calls travel over your Internet connection. You need to have a reliable network and an adequate, stable Internet connection at each site. Also, it is often possible to actually reduce monthly telecom expenses by moving to a hosted solution, but existing businesses may find that they are locked into carrier contracts making it difficult to maximize the benefits of a hosted service until their contract expires. As always, it is crucial look at the complete picture before making any decisions on telephone systems, telephone lines, or Internet/data circuits. They go hand in hand in designing your optimal solution. Also don't let your carrier contracts auto renew with out reviewing your needs. Almost all telecom carriers now have provisions in their agreements that require at least 60 days notice before a contract expires or you will auto renew, often for another full term! Finally, many national hosted PBX providers only offer support via phone or online leaving the customer to work through much of the process on their own. For many businesses, a provider with local staff and technicians that can roll a truck to your locations may be the best choice.
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