Alvarion BreezeMAX PRO-S CPE, Руководство по эксплуатации продукта

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Glossary
BreezeMAX CPEs Product Manual 137
RT Real Time. Real Time service is designed to meet the needs of Real
Time Variable Bit Rate (RT-VBR) like services characterized by
requirements for guaranteed rate and delay such as streaming video or
audio. These services are dynamic in nature, but offer periodic
dedicated requests opportunities to meet real-time requirements.
Because the subscriber equipment issues explicit requests, the
protocol overhead and latency is increased, but capacity is granted
only according to the real needs of the connection. Service parameters
include CIR and CT.
Rx Receive
SAU SU Alignment Unit
SDARS Satellite Digital Audio Radio Service. A satellite-based direct-broadcast
radio service in which digitally encoded audio entertainment material
is broadcast to earth-based receivers from an orbiting satellite, either
directly or via a repeater station.
SIP Session Initiation Protocol. An application-layer control IETF protocol
that can establish, modify, and terminate multimedia sessions such as
Internet telephony calls (VoIP). SIP can also invite participants to
already existing sessions, such as multicast conferences. Media can be
added to (and removed from) an existing session. SIP transparently
supports name mapping and redirection services, which supports
personal mobility - users can maintain a single externally visible
identifier regardless of their network location.
SNMP Simple Network Management Protocol. A network management
protocol that provides a means to monitor and control network
devices, and to manage configurations, statistics collection,
performance, and security. SNMP works by sending messages, called
protocol data units (PDUs), to different parts of a network.
SNMP-compliant devices, called agents, store data about themselves in
Management Information Bases (MIBs) and return this data to the
SNMP requesters.
SNR Signal to Noise Ratio. The ratio of the amplitude of a desired analog or
digital data signal to the amplitude of noise in a transmission channel
at a specific point in time. SNR is typically expressed logarithmically in
decibels (dB). SNR measures the quality of a transmission channel or a
signal over a network channel. The greater the ratio, the easier it is to
identify and subsequently isolate and eliminate the effects of noise.
SNR also is abbreviated as S/N.
SU Subscriber Unit