Emergency Phone Number Services - E911 - AudioCodes Mediant 800 MSBG User Manual

For example, assume that you want to manipulate an incoming IP call with destination
number +5492028888888 (area code 202 and phone number 8888888) to the number
0202158888888. To perform such a manipulation, the following configuration is required in
the Number Manipulation table:
1. The following notation is used in the 'Prefix to Add' field:
0[5,3]15
where,
•
0 is the number to add at the beginning of the original destination number.
•
[5,3] denotes a string that is located after (and including) the fifth character (i.e.,
the first '2' in the example) of the original destination number, and its length being
three digits (i.e., the area code 202, in the example).
•
15 is the number to add immediately after the string denoted by [5,3] - in other
words, 15 is added after (i.e. to the right of) the digits 202.
2. The first seven digits from the left are removed from the original number, by entering
"7" in the 'Stripped Digits From Left' field.
In this configuration, the following manipulation process occurs: 1) the prefix is calculated,
020215 in the example; 2) the first seven digits from the left are removed from the original
number, in the example, the number is changed to 8888888; 3) the prefix that was
previously calculated is then added.
8.3.3

Emergency Phone Number Services - E911

The device supports emergency phone number services. The device supports the North
American emergency telephone number system known as Enhanced 911 (E911),
according to the TR-TSY-000350 and Bellcore's GR-350-Jun2003 standards. The E911
emergency system automatically associates a physical address with the calling party's
telephone number, and routes the call to the most appropriate (closest) Public Safety
Answering Point (PSAP), allowing the PSAP to quickly dispatch emergency response (e.g.,
police) to the caller's location.
Typically, the dialed emergency number is routed to the appropriate PSAP by the
telephone company's switch, known as a 911 Selective Router (or E911 tandem switch). If
the PSAP receives calls from the telephone company on old-style digital trunks, they are
specially formatted Multi-Frequency (MF) trunks that pass only the calling party's number
(known as Automatic Number Identification - ANI). Once the PSAP receives the call, it
searches for the physical address that is associated with the calling party's telephone
number (in the Automatic Location Identification database - ALI).
SIP User's Manual
Figure 8-16: Prefix to Add Field with Notation
420
Mediant 800 MSBG
Document #: LTRT-12804