Documentation on the E911 System
March 1988
$79,449, 6 pages
Bell South Standard Practice
660-225-104SV
Review by Emmanuel Goldstein

It otherwise would have been a quickly forgotten text published in a hacker
newsletter. But due to all of the commotion, the Bell South E911 document is
now very much in the public eye. Copies are extremely easy to come by, despite
Bell South's assertion that the whole thing is worth $79,449.

While we can't publish the actual document, we can report on its contents since
it's become a news story in itself. But don't get excited. There really isn't
all that much here.

Certain acronyms are introduced, among them Public Safety Answering Point
(PSAP), also known as Emergency Service Bureau (ESB). This is what you get (in
telco lingo) when you dial 911. The importance of close coordination between
these agencies is stressed. Selective routing allows the 911 call to be routed
to the proper PSAP. The 1A ESS is used as the tandem office for this routing.
Certain services made available with E911 include Forced Disconnect,
Alternative Routing, Selective Routing, Selective Transfer, Default Routing,
Night Service, Automatic Number Identification, and Automatic Location
Identification.

We learn of the existence of the E911 Implementation Team, the brave men and
women from Network Marketing who help with configuration in the difficult
cutover period. This team is in charge of forming an ongoing maintenance


We learn that the Switching Control Center (SCC) "is responsible for E911/1AESS
translations in tandem central offices". We're not exactly shocked by this
revelation.

We also find out what is considered a "priority one" trouble report. Any link
down to the PSAP fits this definition. We also learn that when ANI fails, the
screens will display all zeroes.

We could go on but we really don't want to bore you. None of this information
would allow a hacker to gain access to such a system. All it affords is a
chance to understand the administrative functions a little better. We'd like to
assume that any outside interference to a 911 system is impossible. Does Bell
South know otherwise? In light of their touchiness on the matter, we have to
wonder.

We'd be most interested in hearing from people with more technical knowledge on
the subject. What does this whole escapade tell us? Please write or call so the
facts can be brought forward.

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2600 Magazine, Volume 7, Number 1, Spring 1990