Write a description of the solution you envisage. Assume that you have chosen Asterisk as the solution. You should include:

1. A description of the architecture - include VoIP, IP telephony, network, and firewall elements
2. A thorough explanation of how your solution will work - the exact process of how calls are made, received, interfaced with the PSTN
3. An explanation of how your solution meets the business requirements
4. A description of each component
5. The rational for the design decisions you made

You need to address these as well Use SIP compatible handsets <- What type of switch is needed to connect VoIP handsets? Provide call parking, call queuing, voice mail, ring groups, and an IVR service