Page 5-62
System Features
INTER-TEL
®
AXXESS
®
MANUAL VERSION 11.0 – May 2008
Terminology
Terminology
10.29 Some common terms associated with Primary Rate and ISDN include the following:
• 2B+D: A 2B+D circuit is divided into two 64 kbps B-channels that can carry voice,
video, or data. It also has a 16 kbps D-channel for low-speed data and signaling. There
are two types of 2B+D interfaces that use different wiring: the “U” interface uses a sin-
gle twisted pair and the “S/T” interface uses two twisted pairs. This is also referred to as
“Basic Rate Interface (BRI).”
• 23B+D: A 23B+D circuit is divided into 23 B-channels (64 kbps each) that can carry
voice, data, and video simultaneously. It also has a 64 kbps D-channel for out-of-band
signaling, call control, and packet data. (NOTE: The Inter-Tel system does not support
the use of the D-channel for packet data.). This interface uses two twisted-pairs of wire.
This is also referred to as “Primary Rate Interface (PRI).”
• 30B+D: This is the standard European ISDN interface. A 30B+D circuit is divided into
30 B-channels (64 kbps) that can carry voice, data, and video simultaneously. It also has
a 64 kbps D-channel for out-of-band signaling and call control, and one framing chan-
nel. This interface uses two twisted-pairs of wire.
• Automatic Call Number Identification (ANI): Automatic Numbering Identification
(ANI) information identifies the caller’s telephone number. The system receives a spec-
ified number of digits. *ANI* is another type of ANI that does not require a specified
number of digits. The system receives a star (*) before the ANI digits to signal the
beginning of the caller’s telephone number. Then there is another star after the digits to
signal the end of the ANI information.
• B-Channel: The B-channel, or “bearer” channel, is the basic component of ISDN inter-
faces. A B-channel can transmit or receive voice or data at up to 64,000 bits per second
(64 kbps).
• B-Channel Negotiation: (Currently not supported) This allows the phone system to
request the channel that is used for each call. When the phone system requests a spe-
cific B-channel for an outgoing call, the network decides which channel is used. How-
ever, if the channel selected by the network is not the requested-channel, the phone
system releases that channel (if seized) and attempts to re-initiate the call using the
channel specified by the network. (For an incoming call, the phone system does need to
request a channel.)
• Bandwidth: The bandwidth of a device determines the frequency range it can handle.
Different types of communications use different bandwidths. For example, telephone
communication requires a relatively narrow bandwidth, while video requires a wide
bandwidth.
• Basic Rate Interface (BRI): Also called 2B+D, BRI provides two 64 kbps B-channels
that can carry voice or data and a 16 kbps D-channel for low-speed data and signaling.
This can be used for homes and Centrex sites that do not require PRI.
• Calling Party Number Service: This service provides the calling party’s line number
(not billing number) to the called party. This is not supported in the current system soft-
ware.
• D-Channel: The data channel, or D-channel, carries the signaling information at
64 kbps for the B-channels in a Primary Rate Interface or at 16 kbps in a Basic Rate
Interface.
To Next Page
Loading...
