Learn how VoIP 911 is different than normal 911 and which 911 services are available to you with a VoIP phone system.
VoIP works differently than PSTN (public switched telephone network) 911. A VoIP phone system is not bound to a specific location like traditional phone service. Because a VoIP line is virtual, it makes tracing calls impossible for emergency services.
Location is crucial to emergency services in North America, where Public Safety Answering Point(s), respond in relation to a caller's geographic location.
Since the inception of VoIP as a viable residential phone service, there has been concern over its effectiveness with emergency services. In 2005, the FCC required all interconnected VoIP providers (hooked up to the PSTN) to be E911 compliant. E911 means Enhanced 911, and it transmits a caller's location to a PSAP.
When choosing which VoIP provider to go with, one of the major criteria should be the availability of 911 service. 911 service is an essential component to your VoIP telephone service, for obvious reasons.
Note that some providers, like Skype, are mobile and/or portable and do not provide 911 services because it is impossible to know the user's current location. VoIP 911 can be problematic in this way, as some VoIP services can be stationary or mobile. For example, Vonage supplies E911 to its users "other than WiFi and Softphone customers."
Historically in the US, there have been two levels of 911 service that VoIP service providers can offer: E911 service and the "10-digit routing technique" 911 service.
As mentioned above, E911 service stands for Enhanced 911 service and is what traditional telephone companies currently provide in most of the US. E911 service gives your local dispatch center or PSAP (Public Safety Answering Point) your name and address automatically when you dial 911. This service can be vital if the caller is unable to speak due to the nature of the emergency.
When signing up for a new VoIP service that offers E911 service, the customer must provide their permanent address to the service provider. This information is then automatically forwarded to the PSAP when the customer calls 911. Although you can transport your VoIP equipment for use in other locations, E911 service is only available from the address on file with the VoIP provider. Thus, a customer who transports their VoIP equipment to another location must update their address information with their VoIP provider before they can use 911 service.
In the past, the "10-digit routing technique" for 911 service was what the majority of VoIP companies provided. This method used routing tables to convert a customer's 911 call into the 10-digit phone number that, in theory, was for the closest emergency dispatch center, and no location information would be automatically provided.
You can read more about routing, VoIP, and emergency services at Avaya's blog.
The FCC discusses different types of 911 and VoIP 911 services below:
12. Basic 911.
Basic 911 service is a forwarding arrangement in which calls dialed to 911 are transmitted from the service provider’s switch to a single geographically appropriate PSAP or public safety agency, usually over dedicated emergency trunks. Basic 911 networks are not capable of processing the caller’s location, but simply forward all 911 calls to the appropriate PSAP or public safety agency. Nor does basic 911 provide PSAP call takers with the caller’s location information or, in some cases, a call back number. Although some emergency systems provide only basic 911 service, most systems have implemented E911 service.13. E911.
E911 systems route 911 calls through the use of a Selective Router to a geographically appropriate PSAP based on the caller’s location. E911 also provides the call taker with the caller’s call back number, referred to as Automatic Numbering Information (ANI), and, in many cases, location information – a capability referred to as Automatic Location Identification (ALI). Both wireline and wireless carriers provide E911 services in many localities.
Anyone thinking of replacing their traditional phone line with a VoIP line should consider only VoIP providers with E911 service for safety reasons. If you are getting a VoIP line as a second line, 911 service may not be as crucial.
However, VoIP 911 service requires two things to function: a broadband Internet connection and electricity. With a VoIP telephone line, your phone service is only as reliable as your Internet connection and the power to your home. In the event that your broadband connection goes down, perhaps due to maintenance or upgrades at your ISP (Internet Service Provider), you will have no telephone service, and thus no 911 service. You will also have no VoIP 911 service in the event of a power outage.
These factors may be unacceptable to some individuals considering replacing their traditional phone line but may be acceptable if they are considering VoIP for a second line. Some VoIP service providers offer equipment that can place calls on the traditional phone network (PSTN) in the event of a power or broadband outage. This is the most reliable solution for an individual wanting to replace their traditional phone line with a VoIP line.