Alcatel Carrier Internetworking Solutions 6800 User Manual

Page of 614
The MAC ASIC
page -6
OmniSwitch Troubleshooting Guide
September 2005
The Coronado ASIC contains both Ingress and Egress functions. Ethernet frames flow from the Catalina 
through the Ingress Coronado, through the Nantucket switch fabric, then through the Coronado Egress 
logic and finally out the Egress Catalina. 
Note: Frames always flow through the Nantucket, even if the input and output ports are on the same Coro-
nado ASIC. One or more Coronado ASIC are located on the network interface cards. It is a store and 
forward technology meaning that the entire PDU must be received before it is transferred across the fabric 
to the egress port. Each Coronado provides 2.4Gbps interface to the backplane.
Coronado has a build-in Hardware Routing Engine known as HRE. This HRE provides the function of 
Layer 2 switching as well as Layer 3 routing. Coronado also has classifier logic built-in, which enables the 
packet to be classified according to the policies defined.
On the Network Interface cards for OmniSwitch 7XXX, there is one Coronado per NI. 
Ethernet switching modules (10/100MB) always have one Coronado for both OmniSwitch 7/8XXX.
OmniSwitch 8800 has four Coronado ASICs (0 t0 3) per NI for all the GNI modules 
Coronado is referred to as a Slice. Therefore, the Coronado on a network interface card in a working chas-
sis is referred to by slot and slice number. 
Functional Description
 
HRE
X
Y
B
U
S
_
R
Queue 
Manager 
X
Y
B
U
S
_
T
Egress Logic 
SPARC
F
B
U
S
_
R
F
A
B
R
I
C
SSRAM 
SDRAM0
SDRAM1
C
a
t
a
l
i
n

A
t
a
l
i
n
a
1 
F
B
U
S
_
T
BBUS