Snom ONE IP Technical Manual page 209

snom ONE • Administrator Guide, Release 5
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E1 (or E-1)
Similar to the North American T-1, E1 is the European format for digital trans-
mission. E1 carries signals at 2 Mbps (32 channels at 64 kbps, with 2 channels
reserved for signaling and controlling), and the T1 carries signals at 1.544 Mbps
(24 channels at 64 kbps). E1 and T1 lines may be interconnected for interna-
tional use.
E.164 [RFC 2916]
An international numbering plan that provides unique phone numbers world-
wide. Each assigned number contains a country code (CC), a national destina-
tion code (NDC), and a subscriber number (SN). An E.164 number can be
up to 15 digits. E.164 may be replaced with ENUM, which is currently being
worked on by the ITU and the IETF. ENUM will encompass both traditional
analog phones and digital devices, including computers and other devices on the
Internet. See also "ENUM."
E911 (Enhanced 911)
A location technology advanced by the FCC that allows mobile phones to iden-
tify to emergency dispatchers the location from which a wireless call is being
made. A 911 call made from a traditional phone with ground wires is routed to
the nearest public safety answering point (PSAP). The PSAP receives the caller's
phone number and the exact location of the phone from which the call was made
and distributes the emergency call to the proper services. In contrast, 911 callers
using a mobile phone had to access their service providers in order to get verifica-
tion of subscription service before the call was routed to a PSAP. A 1996 FCC
ruling changed this. Now a 911 call must now go directly to the PSAP without
receiving verification of service from a specific cellular service provider. The call
must be handled by any available service carrier even if it is not the cellular phone
customer's specific carrier. The FCC rules also require that all mobile phones
manufactured for sale in the United States after February 13, 2000, that are
capable of operating in an analog mode, must include Enhanced 911 support.
Since May 19, 2005, E911 support is required for certain VoIP service.
ENUM (Electronic NUMbering) [RFC 3761]
A protocol from the IETF that uses the domain name system (DNS) to convert
a telephone number to an IP address and vice versa, enabling it to be resolved