Overview of the Model 5782 ATM Virtual Network Router
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About the Model 5000BH Backplane
The Model 5000BH ATM/Router Backplane integrates two bus technologies
(
Figure 1-4
):
•
Centillion ATM bus
•
Bay Networks Parallel Packet Express (PPX
®
) router bus
Figure 1-4.
Model 5000BH ATM/Router Backplane Bus Structure
Centillion Architecture
The Centillion architecture for the Model 5000BH backplane is based on a
distributed, parallel ATM switching engine and is the common denominator over
which both cell and frame switching can be implemented. As an internal switch
fabric, ATM is transparent to users; with the addition of ATM port interfaces,
however, the Model 5000BH chassis backplane can immediately forward both
LAN and ATM traffic.
Model 5782 VNR modules attach to one of two Centillion ATM buses on a Model
5000BH backplane. Switching in a Model 5000BH chassis spans 12 of 14 slots.
Each Centillion ATM bus spans six slots (slots 2 through 7 and 8 through 13).
The architecture includes several advanced hardware components:
•
3.2 Gb/s ATM backplane that offers an ultra-high-speed, consistently
low-latency transport (10
microseconds) between switch modules.
•
Application-specific integrated circuit (ASIC) located on every switch module
to manage ATM backplane transfers and all switching locally on the module.
Each ATM module has 1.2 Gb/s of local switching capacity.
6750EC
Centillion ATM bus
Centillion ATM bus
Slot
2
3
4
5
6
7
8
9
10 11 12 13
PPX router bus