Currently, there are various types of emergency response systems used throughout the world, which includes the basic 911, enhanced 911, wireless 911, VoIP 911, and next-generation 911.

Difference between various types of emergency response systems

Basic 911

As the name suggests, it refers to the traditional emergency systems, which was started in 1968. As it is based on verbal communication, so the caller needs to provide the respective location verbally to the operator. There is no additional information for display regarding the caller, such as phone number and name. The caller is routed to the respective operator through NPA (Number Planning Area) or area code. Some of the drawbacks of the system include no response in case of a large number of calls at a time, no actual tracing option, more fake calls, and no response after a disaster.

Enhanced 911 (E911)

E911 is a more advanced form of the basic 911, as it has the ability to display the phone number and address of the caller to the 911 operator. The call is routed through ALI (automatic location identification) database, as ALI database contains the 911 addresses of every associated phone numbers. When the call is made for 911, ALI provides the nearest responder according to the address associated with that number. The E911 was mandated with the Wireless Communications and Public Safety Act, in 1999.

Wireless Enhanced 911 (Wireless E911)

The excessive use of mobile phone also increases the complexity of emergency responding, as most callers can now call from their mobile phones which can be from anywhere. To get the appropriate location of mobile emergency caller, the handset location is used which provide more accurate location as compared to ALI database. The calls for wireless E911 are routed to the appropriate emergency responder through the cell tower or antenna used by the caller for the emergency call.

VoIP 911

VoIP (voice over IP) is the transfer of voice data over IP of internet. It was mandated in 2005 by the FCC for interconnected VoIP providers. In VoIP case, the name of the caller and the associated address is also shown to the 911 operator. For displaying the address and name of the caller, multi-service access gateway (MSAG) database is used. In VoIP to find the location of the caller VoIP Position Centre analyses is used, which provide the appropriate location of the caller. Then according to the location call is routed to correct emergency dispatch.

Next Generation 911 (NG9-1-1)

The NG9-1-1 is quite advanced from, as it has the ability to send photos, video and text messaging to the 911 operator, which helps in quickly identifying the required emergency dispatch. It uses the PIDF-LO (Presence Information Data Format-Location Object) for identifying the location of the caller. PIDF-LO is a standard which is used to represent the address in XML format.