Specifications

Circuit packs, channel service units, and power supplies
222 Hardware Description and Reference for Avaya Communication Manager
TN464HP DS1 interface, T1 (24 channels) or E1 (32
channels)
The TN464HP circuit pack provides:
● Circuit-pack-level, administrable A- or Mu-Law companding
● CRC-4 generation and checking (E1 only)
● Stratum-3 clock capability
● ISDN-PRI T1 or E1 connectivity
● Line-out (LO) and line-in (LI) signal leads for unpolarized, balanced pairs
● Support for CO, TIE, DID, and off-premises station (OPS) port types that use any of the
following protocols:
- robbed-bit signaling protocol,
- proprietary bit-oriented signaling (BOS) 24th-channel signaling protocol, or
- DMI-BOS 24th-channel signaling protocol
● Support for Russian incoming ANI
● Support for universal, digital, signal level-1equipment in wideband ISDN-PRI applications
● Test-jack access to the DS1 or E1 line, and support of the 120A integrated channel-service
unit (ICSU) module
● Support for the enhanced maintenance capabilities of the ICSU. These circuit packs can
communicate with Avaya Interactive Response System.
● Downloadable firmware
● Support for echo cancellation.
The echo cancellation capability of the TN464HP is selectable on a per-channel basis. The
TN464HP DS1 interface automatically turns off echo cancellation when the interface
detects a 2100-Hz phase-reversed tone generated by high-speed modems (56-kbps). But
the interface does not turn off echo cancellation when the interface detects a 2100-Hz
straight tone generated by low-speed modems (9.6-kbps). Echo cancellation improves a
low-speed data call.
The TN464HP DS1 interface is intended for customers who are likely to encounter echo.
This echo can be over circuits that are connected to the public network. The occurrence of
echo is higher if the switch is configured for ATM, IP, or other complex services and
interfaces to certain local service providers. These local service providers do not routinely
install echo cancellation equipment in all their circuits. A common source of echo is "hybrid"
circuits, where conversions between 2-wire analog circuits and 4-wire digital circuits take
place. The TN464HP DS1 interface cancels echo with delays of up to 96 milliseconds.