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LGR User Guide and Technical Manual
Term
Defi nition
SIM Card
A Subscriber Identity Module or SIM is an integrated circuit that stores the
International Mobile Subscriber Identity [IMSI] and key used to identify and
authenticate subscribers on mobile telephony devices. A SIM card contains:
•
its unique serial number [ICC ID]
•
International Mobile Subscriber Identity [IMSI]
•
security authentication and ciphering information
•
temporary information related to the local network
•
a list of the services the user has access to
•
two passwords: a personal identifi cation number [PIN] for ordinary
use and a personal unblocking code [PUK] for PIN unlocking
The primary advantage of cellular wireless data is that you have access to the
Internet from any location, indoors or outdoors, throughout your carrier’s data
coverage area. A disadvantage – as is prevalent with cellular telephones – is
that cellular coverage can be attenuated indoors, as well as in remote areas.
SNR
Signal-to-Noise Ratio
A measure of signal strength and quality that is defi ned as the ratio of the
amplitude of a signal compared to the amplitude of the background noise.
SNR is typically measured in decibels [dB].
SSID
The Service Set Identifi er [SSID] is a case-sensitive, alphanumeric, 32 -
character unique identifi er attached to the header of packets sent over a
wireless local-area network [WLAN] that acts as a password when a mobile
device attempts to connect with a Basic Service Set [BSS] which is a
component of the IEEE 802.11 WLAN architecture. An SSID is also referred
to as a Network Name because essentially it is a name that identifi es a
wireless network.
The SSID differentiates one WLAN from another, so all Access Points and all
devices attempting to connect to a specifi c WLAN must use the same SSID to
enable effective roaming. As part of this association process, a wireless client
must have the same SSID as that entered in the Access Point or it will not be
permitted to join the BSS.
