Utilizing one of the most traditional and available technologies available, a company can create a fairly reliable back up plan for voice. This technology is copper lines. By installing a block of copper lines, a company can at least make and in some cases (based on the carrier) receive incoming calls if a phone system or T1 is to fail. In this scenario I suggest identifying a few key employees or departments. Once this is identified, each user should get the following:
1) A single voice jack at their desk or office, use a red or orange jack so it is easily identified by the user
2) An analog phone, either kept at the desk or in a common area.
If the phone system or T1 is to fail, each user can plug-in the analog phone to the identified jack and use the existing copper lines to keep call flow for incoming and outgoing calls moving. Although this is not ideal, and there may be some cost for extra voice locations and phones, it is one way to avoid customers not getting through to a business by utilizing existing technologies.
