MT90883 Datasheet, PDF (26/97 Pages) Zarlink Semiconductor Inc – TDM to Packet Processors

MT90880/1/2/3
Data Sheet
H.100/H.110
bus segment
H.100/H.110
bus segment
H.100/H.110
bus segment
MT90866
H.110
Switch
MT90880
TDM-IP
Processor
MT90866
H.110
Switch
MT90880
TDM-IP
Processor
MT90866
H.110
Switch
MT90880
TDM-IP
Processor
Ethernet
Ethernet
MVTX2604
Ethernet
Switch
Ethernet
Figure 8 - H.100/H.110 Expansion using Ethernet Switching Fabric
5.0 Functional Operation
5.1 Overview
The MT9088x family provides the data-plane processing to enable constant bit rate TDM services to be carried
over a packet network, such as an Ethernet or IP network. The device segments the TDM data into user-defined
packets, and passes it transparently over the packet network to be reconstructed at the far end. This has a
number of applications, including packet backplanes for TDM-based equipment, and emulation of TDM circuits
(similar to the circuit emulation services for ATM, see references 5 and 6).
The advantages of using a packet medium for transport and distribution of TDM services include:
Scalability
Efficiency
Service provisioning
Cost
Physical distribution
TDM-based systems are hard to scale in capacity for two main reasons:
• TDM clock frequency increases in proportion to the number of input channels, and
this high frequency clock must be distributed around the system while maintaining
accurate phase alignment
• Physical limitations - the form factor of hard backplane systems effectively restrict
the TDM backplane to a single rack, limiting the size of the system that can be
connected
TDM equipment dedicates capacity to all channels, whether in use or not. Use of a
packet-based system allows the available bandwidth to be statistically multiplexed,
taking advantage of the fact that not all channels are active all the time.
It is easier to add new services by adding new line input cards or resource cards.
These are not constrained to be in the same physical rack, as with a TDM
backplane system.
Network hardware is readily available at lower cost than equivalent TDM
equipment, reducing the overall cost of ownership.
Equipment may be physically distributed over a wider area, connected either by
simple twisted pair network cable, or by fibre. This allows the footprint for
co-located equipment (for example) to be small, with the main resources located
elsewhere on the network.
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Zarlink Semiconductor Inc.