You need to ask your network administrator regarding any special setting that is required to function through the firewall. Emergency 911 calls are one of the most difficult technical problems of VoIP. The main problem is that it is hard to determine your physical location when you are making a VoIP phone call, so 911 calls may not be routed to the correct call center, and even if they are, the operators cannot determine your location if you are unable to speak.
Various VoIP reseller white label have come up with a number of solutions including registering your address with the provider, having a notification system that calls friends and relatives, as well as hardware solutions built into the VoIP equipment. When choosing a VoIP Service provider you must check what type of 911 service they provide, and how it is set up.
You may want to keep your existing phone number when signing up for a VoIP service. If the service provider offers local phone numbers in your area, there’s a chance that you can keep your old phone number, but there is no guarantee and it may not be possible to keep your old telephone number when you switch to a VoIP service. At this, you check with EMERGENCY SERVICES – 911/E911.
Emergency 911 service is yet to be available with many Voice over IP services in most area. Some providers in fact will only let you make OUTBOUND calls from your home because of this (they want you to keep a land line for now).
For those where it does work it depends on the correct data being entered in their master database somewhere and for the routing algorithms to work correctly for your call to get to the correct 911 emergency call center.
Traditional landlines have a variety of legal protections, but not VoIP phone service.
In the United States, the FCC (Federal Communications Commission) is demanding that VoIP service providers come up with a solution that allows emergency VoIP calls to be accurately situated, and VoIP service providers are actively searching for a way to provide this service.