Mitel DISTRIBUTED HYPERCHANNEL MT90840 - Manual (Page 31)

Preliminary Information
MT90840
2-261
Applications
Distributed Isochronous Network
Low latency isochronous backbones provide for the
deployment of systems that require cost effective
implementation, high bandwidth, predictable data
transfer delays and direct synchronization with the
wide area network.
Some applications in Computer Telephony
Integration (CTI) require a large amount of
bandwidth to be transported between multiple
chassis within the same location, or between
separate locations. The MT90840 is ideal for
implementing physically distributed transport and
switching systems for multi-chassis or inter-shelf
communications.
The MT90840 bridges existing Mitel ST-BUS
components into a new networking environment
where mixed data, voice and video signals can be
time-interchanged or multiplexed from serial PCM
streams onto serial high-speed time-division-
multiplex (TDM) isochronous backbones operating at
SONET rates such as 51 (STS-1) or 155 Mbps
(STS-3).
Today, transmission links operating at SONET rates
utilize serial-to-parallel and parallel-to-serial
converters (or framers) which perform embedded
framing functions and give the user access to the
payload of the high speed frame. The MT90840
provides an 8-bit bidirectional parallel data port
which directly interfaces to a high-speed framer
parallel data interface, allowing designers to build
distributed networking systems with interconnection
speeds up to 155 Mbps. Figure 16 shows an
example of a distributed networking application in a
CTI system.
The MT90840's clock synchronization and reference
options allow many applications and topologies when
isochronous TDM backbones are required. Two
major clock synchronization schemes provided by
the MT90840 allow the serial port interface (ST-BUS)
to provide the master clock and frame reference
signals for the distributed high speed backbone
(master operation) or to derive the entire ST-BUS
clock and frame reference signals from the high
speed backbone (slave operation). This type of
Figure 16 - CTI Distributed Architecture Implemented with the MT90840
MT8977/9079
T1 & E1 I/F
Call
Processing
ST-BUS
MT896x
Filter/Codec
ST-BUS
ISO Ethernet
MUX
ST-BUS
LAN ADAPTER CARD
PSTN
24/30B+D
CTI
SERVER
CTI
SERVER
Up to 2400 TDM
Interchassis Signalling
(e.g. Mitel’s Connection
CTI Server
Switching
BUS
e.g.; MVIP
155 Mbps
Framing &
Optics
MT90810
FMIC
MT90840
MT90810
FMIC
MT8985/6
EDX
channels of user data
Master Software)
Filter/Codec
MT8930 / 71
(2B+D) I/F