Citrix ByteMobile T1010, Установка, настройка и администрирование

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T-Series Traffic Director Installation, Configuration and Administration Guide Glossary-3
Glossary
DNIS Dialed Number Identification Service. A feature of 800 and 900 lines that provides the number that
the caller dialed to reach the call center. This called number information is used to route the call to
the appropriate service. This feature also allows one trunk group to service multiple applications.
DNS Domain Name System. DNS is a distributed database that is used by TCP/IP applications to map
IP addresses to alphanumeric host names. The DNS server maintains a database of domain names
(host names) and their corresponding IP addresses.
DTMF Dual Tone Multi-Frequency tones, or touch-tones. Commonly known as touch-tone or push-button
dialing, as opposed to older-style pulse or rotary dialing. Touch-tones are combinations of two
tones, one high frequency and one low frequency.
GSM supports full-originating DTMF.
EDGE Enhanced Data rates for Global (or GSM) Evolution. EDGE is an enhancement to the GSM and
TDMA wireless communications systems that increases data throughput to 384 Kbps.
EMS Element Management System. A T-Series application that allows administrators to manage
multiple T-Series devices.
encryption A method of altering the appearance of the data to make it incomprehensible to those who are not
authorized to see the information.
event A message that alerts a process that a task has finished or that an external event has occurred.
failover The transfer of function from a failed component to an alternate one while preserving the
operational state of the overall system. See also
switchover .
fault tolerant The ability to continue non-stop when a hardware failure occurs. A fault-tolerant system is
designed for reliability by building multiples of all critical components, such as CPUs, memory,
disks, and power supplies into the same system. In the event one component fails, another takes
over without stoppage in the system.
firewall A router or access server that has been designated as a buffer between a public network and a
private network. A firewall router uses access lists and other methods to ensure the security of the
private network.
gateway A network server that connects two otherwise incompatible networks, network nodes,
subnetworks, or devices. For example, a
VoIP gateway bridges the PSTN and an IP network for
voice calls. Gateways perform protocol-conversion operations across a broad spectrum of
communications functions or layers.
GGSN Gateway GPRS Support Node. The GGSN is a wireless gateway that allows mobile cell phone
users to access the public data network or specified private IP networks.
GPRS General Packet Radio Service, a standard for wireless communications. Runs up to 115
kilobits/sec. Suited for sending/receiving small bursts of data, such as e-mail, Web, and large
volumes of data.
GRE Generic Routing Encapsulation. GRE is a layer 3 protocol that is used primarily to encrypt traffic.
It can also provide data encapsulation to allow tunneling. It supports both IP and non-IP protocols.