Planning for VoIP is easier if you develop a VoIP requirements list. Some of the more obvious needs your VoIP requirements list should take into consideration includes the end-user features and services that are needed. Additionally, your requirements list will be a better planning tool if you include the network requirements necessary to support VoIP. Finally, your VoIP requirements list should address all of the administrative overhead necessary to deploy, operate, and replace VoIP systems.
VoIP systems are known for the rich set of user features they provide. A VoIP requirements list will provide you with the opportunity to verify that the capabilities needed by your users are included in the system you choose. This is not an area to take for granted because some of the better known services don't include capabilities that you may require. For example, while most systems provide the Caller ID number many don't provide the equally useful Caller ID name. Will your calls still be forwarded if the power fails? Will the system automatically block telemarketer tone? Are 800 numbers supported and is auto redial available? A VoIP requirements list helps to insure that you validate your requirements before making a selection.
Voice makes different demands of networks than data. Computers don't mind if data arrives out of sequence but humans expect their voice conversations to be linear. To satisfy voice network requirements for jitter, latency, packet loss, and quality of service may require not only bandwidth upgrades to IP networks but also a minimum of router reconfigurations. Your VoIP requirements lists should also include security planning. Will your voice calls need encryption?
To administer your VoIP systems and networks management software will be required. Remember you will need to constantly monitor the aforementioned network performance parameters to insure that the network continuously supports the level of quality you need. In order to have the administrative and technical management systems in place prior to deploying VoIP you will want to include this important area of consideration in your planning and VoIP requirements list preparation phase.