Specifications

Circuit packs, channel service units, and power supplies
250 Hardware Description and Reference for Avaya Communication Manager
channels support the LAPD protocol. However, the TN2185B does not terminate on LAPD
protocol. The S-interface does not support switching of both B channels together as a 128-kbps
wideband channel.
The TN2185B has a maximum range up to 18,000 feet (5486 meters) from the system to the
NT1 device. In an environment with multiple telephones, the B channels are shared only on a
per-call basis. For example, if Channel B2 is for data, then the use of this channel by one
telephone excludes the others from having access to Channel B2. When a device
communicates over the D-channel to access B1 or B2, that channel is owned until the call is
taken down. The D-channel is always shared among the terminals. The TN2185B circuit pack
can be used as an alternative to the TN464 circuit pack or the TN2464 circuit pack.
The TN2185B supports the ability to outpulse in-band DTMF signals or end-to-end signaling.
QSIG Call Completion is supported, but QSIG Supplementary Services are not. ISDN-BRI
trunks can be used as inter-PBX tie lines that use the QSIG peer protocol.
TN2198 ISDN-BRI U interface (2-wire, 12 ports)
The TN2198 circuit pack allows connection to the ANSI standard 2-wire U-Interface. The 2-wire
interface from the TN2198 connects to an NT1 network interface. The 4-wire interface on the
other side of the NT1 can connect to one or two telephones. Unlike the TN2185 circuit pack, the
TN2198 does not provide a trunk-side interface.
The TN2198 contains 12 ports that interface at the ISDN U reference point. For each port,
information communicates over two 64-kbps bearer channels called B1 and B2. Information
also communicates over a 16-kbps channel called the demand channel, or D-channel. The
D-channel is used for signaling. Channels B1 and B2 can be circuit-switched simultaneously.
The D-channel is always packet-switched. The TN2198 requires a packet control circuit pack.
Each port supports one telephone, such as the 500 rotary dial analog telephone and 2500
DTMF dial telephones.
The D-channel supports the LAPD protocol and is consistent with the CCITT Q.920
recommendations for D-channel signaling.
In an environment with multiple telephones, the B channels are shared only on a per-call basis.
For example, if the B2 channel is used for data, then the use of B2 by one telephone excludes
the other telephones from having access to the B2 channel. When a device communicates over
the D-channel to access B1 or B2, that channel is owned until the call is taken. The D channel is
always shared among the telephones. The TN2198 interfaces with the TDM bus and the packet
bus in the switch backplane and terminates with 12 ISDN basic access ports.
The TN2198 has a maximum range of 18,000 feet (5486 meters) from the system to the NT1
device and uses standard protocol ANSI T1.601. The TN2198 has a 160-kbps line rate, that
consists of:
● Two bearer channels at 64 kbps each
● A D-channel at 16 kbps