Section 38: Glossary
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T E C H N O L O G Y
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Section 38.
Glossary
Basic Rate Interface (BRI) The Basic Rate Interface (BRI) of ISDN consists of 2
bearer (B) channels at 64 Kbps each and 1 delta (D)
channel at 16 Kbps, i.e. (2B +D). The total raw data rate
is 144Kbps on a single twisted pair. This can be provided
over a 2 wire facility and the two B channels can be
bonded together to form a single 128Kbps channel.
Central Office (CO)
One of a local telephone company’s offices. Circuits are
run from here to support the surrounding area and ISDN
circuits can extend up to 3.42 miles (5.5 km) from the
CO.
Codec
A codec (coder/decoder) is an integrated circuit device
that encodes an analog signal into a digital bit stream
and then decodes this bit stream into an analog signal.
CSD
Circuit Switched Data (CSD) is provided as part of the
GSM system. The basic data rate is 9,600bps. (see also
WAP and HSCSD)
Customer Equipment (CE) Telecommunications equipment used by an organization
and connected to an ISDN line.
B (Bearer) Channel
A 64Kbps ISDN channel that can be used for carrying
voice, video or data. The channels are known as B1 and
B2.
BOOTP
Bootstrap protocol is used by a network node when
determining the IP address of its Ethernet interfaces.
D (Delta) Channel
The channel carrying all signaling between the network
and the customer’s equipment when using ISDN
channels.
DHCP
This is a method of dynamically allocating IP addresses
so that the addresses are able to be reused when hosts no
longer require them.
Directory Number
A Directory Number is the ISDN number assigned to
each B channel of an ISDN connection.
EDGE
Further enhancements in data capability over the core
GSM network will be provided with the introduction of
Enhanced Data rates for GSM Evolution - known as
EDGE*. This will achieve the delivery of advanced
mobile services such as the downloading of video and
music clips, full multimedia messaging, high-speed color
Internet access and e-mail on the move. (Information
courtesy of GSMworld.com)
