ZyXEL Communications X2002, User Manual

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Chapter 22 Call Services
X2002 User’s Guide
324
22.1.2 What You Need to Know
The following terms and concepts may help you as you read through the chapter.
About Emergency Calls and VoIP
In the past, many commercial VoIP phone services have lacked the ability to deal
correctly with emergency calls. Such VoIP services have been unable either to
connect emergency calls to an emergency dispatcher (at a Public Safety
Answering Point, or PSAP), or to adequately provide information on the caller’s
whereabouts to the dispatcher.
For this reason, the FCC (the Federal Communications Commission of the United
States) has imposed “Enhanced 911” (E911) obligations on providers of
“interconnected VoIP” services. Interconnected VoIP services are those that, in
addition to making calls over the Internet, also connect to the regular public
telephone network. E911 systems not only route emergency calls made from VoIP
accounts to emergency dispatchers, but also provide information on the call’s
originating number and, usually, location information.
However, this system still has disadvantages over traditional emergency call
service. For example, the physical location provided to the PSAP is usually the
account-holder’s address as registered with the VoIP provider; this is not
necessarily the location from which the VoIP account is being used. Furthermore,
VoIP emergency calls are subject to the limitations of the Internet connection over
which they are made, which may be unreliable. Also, VoIP services that do not
directly connect to the public telephone network are not required to adhere to the
FCC’s E911 regulations. Lastly, the E911 service is available only in North America.
Similar systems exist elsewhere in the world, but regulation and implementation
may vary.
For these reasons, the X2002 routes all calls made to the emergency numbers you
configure via its FXO interface whenever possible. The X2002 drops an ongoing
FXO call if necessary.
22.1.3 Before You Begin
Emergency Calls
Before you configure emergency calling, ensure that you are aware of all local
emergency call numbers used in the location where the X2002 is to operate. Bear
in mind that emergency calls may be made to phone numbers other than the
standard public emergency services number (to a private security company or
medical facility, for example).