MT90880B ZARLINK [Zarlink Semiconductor Inc], MT90880B Datasheet - Page 23

• Manufacturer Part Number: MT90880B
• Description: TDM to Packet Processors
• Manufacturer: ZARLINK [Zarlink Semiconductor Inc]

4.4
In a similar manner to the internet off-load solution outlined above, the MT9088x devices can also be used to
route traffic to a remote resource pool. This allows resources to be centralized, with multiple line cards
accessing the resource pool via the Ethernet switching fabric. A typical application for this is a remote access
concentrator for dial-up modem traffic, and Figure 5 shows an example of this.
The MT90880 on the line card forms the modem data into packets, which are transmitted via the Ethernet
switch to a remote DSP pool. The MT90880 on the remote card converts the packets back to TDM and forwards
them to the DSP pool over the TDM link. The demodulated data is then transmitted back over the packet
network to the router via the MT90880.
This packet-based architecture can be easily extended to support large numbers of modem calls by simply
adding more Ethernet switch interfaces. The architecture can also support ISDN PPP traffic. The DSP pool
strips off the HDLC framing and forwards the packets to the MT90880 for transmission over the IP packet
network.
Remote Access Concentration
PSTN
Figure 5 - Remote Access Concentrator using the MT90880
T1/E1/
ISDN
Line Input Card
Line Input Card
DSP Pool
Remote
MT9076
MT9076
Modem
Framer
Framer
Zarlink Semiconductor Inc.
MT90880/1/2/3
23
Modulated
TDM
TDM
PCI
Traffic
MVTX2604
Processor
Processor
MT90880
MT90880
Ethernet
TDM-IP
TDM-IP
Switch
Ethernet
Demodulated
packet data
Ethernet
IP Router
Packet
Data Sheet